aboutsummaryrefslogtreecommitdiff
path: root/sbin/ifconfig/ifconfig.8
blob: 280baaa3fd560052ac69553934128d8d71945294 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
.\" Copyright (c) 1983, 1991, 1993
.\"	The Regents of the University of California.  All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 4. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\"     From: @(#)ifconfig.8	8.3 (Berkeley) 1/5/94
.\" $FreeBSD$
.\"
.Dd September 13, 2011
.Dt IFCONFIG 8
.Os
.Sh NAME
.Nm ifconfig
.Nd configure network interface parameters
.Sh SYNOPSIS
.Nm
.Op Fl L
.Op Fl k
.Op Fl m
.Op Fl n
.Ar interface
.Op Cm create
.Ar address_family
.Oo
.Ar address
.Op Ar dest_address
.Oc
.Op Ar parameters
.Nm
.Ar interface
.Cm destroy
.Nm
.Fl a
.Op Fl L
.Op Fl d
.Op Fl m
.Op Fl u
.Op Fl v
.Op Ar address_family
.Nm
.Fl l
.Op Fl d
.Op Fl u
.Op Ar address_family
.Nm
.Op Fl L
.Op Fl d
.Op Fl k
.Op Fl m
.Op Fl u
.Op Fl v
.Op Fl C
.Nm
.Op Fl g Ar groupname
.Sh DESCRIPTION
The
.Nm
utility is used to assign an address
to a network interface and/or configure
network interface parameters.
The
.Nm
utility must be used at boot time to define the network address
of each interface present on a machine; it may also be used at
a later time to redefine an interface's address
or other operating parameters.
.Pp
The following options are available:
.Bl -tag -width indent
.It Ar address
For the
.Tn DARPA Ns -Internet
family,
the address is either a host name present in the host name data
base,
.Xr hosts 5 ,
or a
.Tn DARPA
Internet address expressed in the Internet standard
.Dq dot notation .
.Pp
It is also possible to use the CIDR notation (also known as the
slash notation) to include the netmask.
That is, one can specify an address like
.Li 192.168.0.1/16 .
.Pp
For the
.Dq inet6
family, it is also possible to specify the prefix length using the slash
notation, like
.Li ::1/128 .
See the
.Cm prefixlen
parameter below for more information.
.\" For the Xerox Network Systems(tm) family,
.\" addresses are
.\" .Ar net:a.b.c.d.e.f ,
.\" where
.\" .Ar net
.\" is the assigned network number (in decimal),
.\" and each of the six bytes of the host number,
.\" .Ar a
.\" through
.\" .Ar f ,
.\" are specified in hexadecimal.
.\" The host number may be omitted on IEEE 802 protocol
.\" (Ethernet, FDDI, and Token Ring) interfaces,
.\" which use the hardware physical address,
.\" and on interfaces other than the first.
.\" For the
.\" .Tn ISO
.\" family, addresses are specified as a long hexadecimal string,
.\" as in the Xerox family.
.\" However, two consecutive dots imply a zero
.\" byte, and the dots are optional, if the user wishes to (carefully)
.\" count out long strings of digits in network byte order.
.Pp
The link-level
.Pq Dq link
address
is specified as a series of colon-separated hex digits.
This can be used to
e.g.\& set a new MAC address on an ethernet interface, though the
mechanism used is not ethernet-specific.
If the interface is already
up when this option is used, it will be briefly brought down and
then brought back up again in order to ensure that the receive
filter in the underlying ethernet hardware is properly reprogrammed.
.It Ar address_family
Specify the
address family
which affects interpretation of the remaining parameters.
Since an interface can receive transmissions in differing protocols
with different naming schemes, specifying the address family is recommended.
The address or protocol families currently
supported are
.Dq inet ,
.Dq inet6 ,
.Dq atalk ,
.Dq ipx ,
.\" .Dq iso ,
and
.Dq link .
.\" and
.\" .Dq ns .
The default if available is
.Dq inet
or otherwise
.Dq link .
.Dq ether
and
.Dq lladdr
are synonyms for
.Dq link .
.It Ar dest_address
Specify the address of the correspondent on the other end
of a point to point link.
.It Ar interface
This
parameter is a string of the form
.Dq name unit ,
for example,
.Dq Li ed0 .
.It Ar groupname
List the interfaces in the given group.
.El
.Pp
The following parameters may be set with
.Nm :
.Bl -tag -width indent
.It Cm add
Another name for the
.Cm alias
parameter.
Introduced for compatibility
with
.Bsx .
.It Cm alias
Establish an additional network address for this interface.
This is sometimes useful when changing network numbers, and
one wishes to accept packets addressed to the old interface.
If the address is on the same subnet as the first network address
for this interface, a non-conflicting netmask must be given.
Usually
.Li 0xffffffff
is most appropriate.
.It Fl alias
Remove the network address specified.
This would be used if you incorrectly specified an alias, or it
was no longer needed.
If you have incorrectly set an NS address having the side effect
of specifying the host portion, removing all NS addresses will
allow you to respecify the host portion.
.It Cm anycast
(Inet6 only.)
Specify that the address configured is an anycast address.
Based on the current specification,
only routers may configure anycast addresses.
Anycast address will not be used as source address of any of outgoing
IPv6 packets.
.It Cm arp
Enable the use of the Address Resolution Protocol
.Pq Xr arp 4
in mapping
between network level addresses and link level addresses (default).
This is currently implemented for mapping between
.Tn DARPA
Internet
addresses and
.Tn IEEE
802 48-bit MAC addresses (Ethernet, FDDI, and Token Ring addresses).
.It Fl arp
Disable the use of the Address Resolution Protocol
.Pq Xr arp 4 .
.It Cm staticarp
If the Address Resolution Protocol is enabled,
the host will only reply to requests for its addresses,
and will never send any requests.
.It Fl staticarp
If the Address Resolution Protocol is enabled,
the host will perform normally,
sending out requests and listening for replies.
.It Cm broadcast
(Inet only.)
Specify the address to use to represent broadcasts to the
network.
The default broadcast address is the address with a host part of all 1's.
.It Cm debug
Enable driver dependent debugging code; usually, this turns on
extra console error logging.
.It Fl debug
Disable driver dependent debugging code.
.It Cm promisc
Put interface into permanently promiscuous mode.
.It Fl promisc
Disable permanently promiscuous mode.
.It Cm delete
Another name for the
.Fl alias
parameter.
.It Cm description Ar value , Cm descr Ar value
Specify a description of the interface.
This can be used to label interfaces in situations where they may
otherwise be difficult to distinguish.
.It Cm -description , Cm -descr
Clear the interface description.
.It Cm down
Mark an interface
.Dq down .
When an interface is marked
.Dq down ,
the system will not attempt to
transmit messages through that interface.
If possible, the interface will be reset to disable reception as well.
This action does not automatically disable routes using the interface.
.It Cm group Ar group-name
Assign the interface to a
.Dq group .
Any interface can be in multiple groups.
.Pp
Cloned interfaces are members of their interface family group by default.
For example, a PPP interface such as
.Em ppp0
is a member of the PPP interface family group,
.Em ppp .
.\" The interface(s) the default route(s) point to are members of the
.\" .Em egress
.\" interface group.
.It Cm -group Ar group-name
Remove the interface from the given
.Dq group .
.It Cm eui64
(Inet6 only.)
Fill interface index
(lowermost 64bit of an IPv6 address)
automatically.
.It Cm fib Ar fib_number
Specify interface FIB.
A FIB
.Ar fib_number
is assigned to all frames or packets received on that interface.
The FIB is not inherited, e.g. vlans or other sub-interfaces will use
the default FIB (0) irrespective of the parent interface's FIB.
The kernel needs to be tuned to support more than the default FIB
using the
.Va ROUTETABLES
kernel configuration option, or the
.Va net.fibs
tunable.
.It Cm ipdst
This is used to specify an Internet host who is willing to receive
IP packets encapsulating IPX packets bound for a remote network.
An apparent point to point link is constructed, and
the address specified will be taken as the IPX address and network
of the destination.
.It Cm maclabel Ar label
If Mandatory Access Control support is enabled in the kernel,
set the MAC label to
.Ar label .
.\" (see
.\" .Xr maclabel 7 ) .
.It Cm media Ar type
If the driver supports the media selection system, set the media type
of the interface to
.Ar type .
Some interfaces support the mutually exclusive use of one of several
different physical media connectors.
For example, a 10Mbit/s Ethernet
interface might support the use of either
.Tn AUI
or twisted pair connectors.
Setting the media type to
.Cm 10base5/AUI
would change the currently active connector to the AUI port.
Setting it to
.Cm 10baseT/UTP
would activate twisted pair.
Refer to the interfaces' driver
specific documentation or man page for a complete list of the
available types.
.It Cm mediaopt Ar opts
If the driver supports the media selection system, set the specified
media options on the interface.
The
.Ar opts
argument
is a comma delimited list of options to apply to the interface.
Refer to the interfaces' driver specific man page for a complete
list of available options.
.It Fl mediaopt Ar opts
If the driver supports the media selection system, disable the
specified media options on the interface.
.It Cm mode Ar mode
If the driver supports the media selection system, set the specified
operating mode on the interface to
.Ar mode .
For IEEE 802.11 wireless interfaces that support multiple operating modes
this directive is used to select between 802.11a
.Pq Cm 11a ,
802.11b
.Pq Cm 11b ,
and 802.11g
.Pq Cm 11g
operating modes.
.It Cm inst Ar minst , Cm instance Ar minst
Set the media instance to
.Ar minst .
This is useful for devices which have multiple physical layer interfaces
.Pq PHYs .
.It Cm name Ar name
Set the interface name to
.Ar name .
.It Cm rxcsum , txcsum
If the driver supports user-configurable checksum offloading,
enable receive (or transmit) checksum offloading on the interface.
Some drivers may not be able to enable these flags independently
of each other, so setting one may also set the other.
The driver will offload as much checksum work as it can reliably
support, the exact level of offloading varies between drivers.
.It Fl rxcsum , txcsum
If the driver supports user-configurable checksum offloading,
disable receive (or transmit) checksum offloading on the interface.
These settings may not always be independent of each other.
.It Cm tso
If the driver supports
.Xr tcp 4
segmentation offloading, enable TSO on the interface.
Some drivers may not be able to support TSO for
.Xr ip 4
and
.Xr ip6 4
packets, so they may enable only one of them.
.It Fl tso
If the driver supports
.Xr tcp 4
segmentation offloading, disable TSO on the interface.
It will always disable TSO for
.Xr ip 4
and
.Xr ip6 4 .
.It Cm lro
If the driver supports
.Xr tcp 4
large receive offloading, enable LRO on the interface.
.It Fl lro
If the driver supports
.Xr tcp 4
large receive offloading, disable LRO on the interface.
.It Cm wol , wol_ucast , wol_mcast , wol_magic
Enable Wake On Lan (WOL) support, if available.
WOL is a facility whereby a machine in a low power state may be woken
in response to a received packet.
There are three types of packets that may wake a system:
ucast (directed solely to the machine's mac address),
mcast (directed to a broadcast or multicast address),
or
magic (unicast or multicast frames with a ``magic contents'').
Not all devices support WOL, those that do indicate the mechanisms
they support in their capabilities.
.Cm wol
is a synonym for enabling all available WOL mechanisms.
To disable WOL use
.Fl wol .
.It Cm vlanmtu , vlanhwtag, vlanhwfilter, vlanhwtso
If the driver offers user-configurable VLAN support, enable
reception of extended frames, tag processing in hardware,
frame filtering in hardware, or TSO on VLAN,
respectively.
Note that this must be issued on a physical interface associated with
.Xr vlan 4 ,
not on a
.Xr vlan 4
interface itself.
.It Fl vlanmtu , vlanhwtag, vlanhwfilter, vlanhwtso
If the driver offers user-configurable VLAN support, disable
reception of extended frames, tag processing in hardware,
frame filtering in hardware, or TSO on VLAN,
respectively.
.It Cm vnet Ar jail
Move the interface to the
.Xr jail 8 ,
specified by name or JID.
If the jail has a virtual network stack, the interface will disappear
from the current environment and become visible to the jail.
.It Fl vnet Ar jail
Reclaim the interface from the
.Xr jail 8 ,
specified by name or JID.
If the jail has a virtual network stack, the interface will disappear
from the jail, and become visible to the current network environment.
.It Cm polling
Turn on
.Xr polling 4
feature and disable interrupts on the interface, if driver supports
this mode.
.It Fl polling
Turn off
.Xr polling 4
feature and enable interrupt mode on the interface.
.It Cm create
Create the specified network pseudo-device.
If the interface is given without a unit number, try to create a new
device with an arbitrary unit number.
If creation of an arbitrary device is successful, the new device name is
printed to standard output unless the interface is renamed or destroyed
in the same
.Nm
invocation.
.It Cm destroy
Destroy the specified network pseudo-device.
.It Cm plumb
Another name for the
.Cm create
parameter.
Included for
.Tn Solaris
compatibility.
.It Cm unplumb
Another name for the
.Cm destroy
parameter.
Included for
.Tn Solaris
compatibility.
.It Cm metric Ar n
Set the routing metric of the interface to
.Ar n ,
default 0.
The routing metric is used by the routing protocol
.Pq Xr routed 8 .
Higher metrics have the effect of making a route
less favorable; metrics are counted as additional hops
to the destination network or host.
.It Cm mtu Ar n
Set the maximum transmission unit of the interface to
.Ar n ,
default is interface specific.
The MTU is used to limit the size of packets that are transmitted on an
interface.
Not all interfaces support setting the MTU, and some interfaces have
range restrictions.
.It Cm netmask Ar mask
.\" (Inet and ISO.)
(Inet only.)
Specify how much of the address to reserve for subdividing
networks into sub-networks.
The mask includes the network part of the local address
and the subnet part, which is taken from the host field of the address.
The mask can be specified as a single hexadecimal number
with a leading
.Ql 0x ,
with a dot-notation Internet address,
or with a pseudo-network name listed in the network table
.Xr networks 5 .
The mask contains 1's for the bit positions in the 32-bit address
which are to be used for the network and subnet parts,
and 0's for the host part.
The mask should contain at least the standard network portion,
and the subnet field should be contiguous with the network
portion.
.Pp
The netmask can also be specified in CIDR notation after the address.
See the
.Ar address
option above for more information.
.It Cm prefixlen Ar len
(Inet6 only.)
Specify that
.Ar len
bits are reserved for subdividing networks into sub-networks.
The
.Ar len
must be integer, and for syntactical reason it must be between 0 to 128.
It is almost always 64 under the current IPv6 assignment rule.
If the parameter is omitted, 64 is used.
.Pp
The prefix can also be specified using the slash notation after the address.
See the
.Ar address
option above for more information.
.\" see
.\" Xr eon 5 .
.\" .It Cm nsellength Ar n
.\" .Pf ( Tn ISO
.\" only)
.\" This specifies a trailing number of bytes for a received
.\" .Tn NSAP
.\" used for local identification, the remaining leading part of which is
.\" taken to be the
.\" .Tn NET
.\" (Network Entity Title).
.\" The default value is 1, which is conformant to US
.\" .Tn GOSIP .
.\" When an ISO address is set in an ifconfig command,
.\" it is really the
.\" .Tn NSAP
.\" which is being specified.
.\" For example, in
.\" .Tn US GOSIP ,
.\" 20 hex digits should be
.\" specified in the
.\" .Tn ISO NSAP
.\" to be assigned to the interface.
.\" There is some evidence that a number different from 1 may be useful
.\" for
.\" .Tn AFI
.\" 37 type addresses.
.It Cm range Ar netrange
Under appletalk, set the interface to respond to a
.Ar netrange
of the form
.Ar startnet Ns - Ns Ar endnet .
Appletalk uses this scheme instead of
netmasks though
.Fx
implements it internally as a set of netmasks.
.It Cm remove
Another name for the
.Fl alias
parameter.
Introduced for compatibility
with
.Bsx .
.It Cm phase
The argument following this specifies the version (phase) of the
Appletalk network attached to the interface.
Values of 1 or 2 are permitted.
.Sm off
.It Cm link Op Cm 0 No - Cm 2
.Sm on
Enable special processing of the link level of the interface.
These three options are interface specific in actual effect, however,
they are in general used to select special modes of operation.
An example
of this is to enable SLIP compression, or to select the connector type
for some Ethernet cards.
Refer to the man page for the specific driver
for more information.
.Sm off
.It Fl link Op Cm 0 No - Cm 2
.Sm on
Disable special processing at the link level with the specified interface.
.It Cm monitor
Put the interface in monitor mode.
No packets are transmitted, and received packets are discarded after
.Xr bpf 4
processing.
.It Fl monitor
Take the interface out of monitor mode.
.It Cm up
Mark an interface
.Dq up .
This may be used to enable an interface after an
.Dq Nm Cm down .
It happens automatically when setting the first address on an interface.
If the interface was reset when previously marked down,
the hardware will be re-initialized.
.El
.Pp
The following parameters are for ICMPv6 Neighbor Discovery Protocol.
Note that the address family keyword
.Dq Li inet6
is needed for them:
.Bl -tag -width indent
.It Cm accept_rtadv
Set a flag to enable accepting ICMPv6 Router Advertisement messages.
The
.Xr sysctl 8
variable
.Va net.inet6.ip6.accept_rtadv
controls whether this flag is set by default or not.
.It Cm -accept_rtadv
Clear a flag
.Cm accept_rtadv .
.It Cm no_radr
Set a flag to control whether routers from which the system accepts
Router Advertisement messages will be added to the Default Router List
or not.
When the
.Cm accept_rtadv
flag is disabled, this flag has no effect.
The
.Xr sysctl 8
variable
.Va net.inet6.ip6.no_radr
controls whether this flag is set by default or not.
.It Cm -no_radr
Clear a flag
.Cm no_radr .
.It Cm auto_linklocal
Set a flag to perform automatic link-local address configuration when
the interface becomes available.
The
.Xr sysctl 8
variable
.Va net.inet6.ip6.auto_linklocal
controls whether this flag is set by default or not.
.It Cm -auto_linklocal
Clear a flag
.Cm auto_linklocal .
.It Cm defaultif
Set the specified interface as the default route when there is no
default router.
.It Cm -defaultif
Clear a flag
.Cm defaultif .
.It Cm ifdisabled
Set a flag to disable all of IPv6 network communications on the
specified interface.  Note that if there are already configured IPv6
addresses on that interface, all of them are marked as
.Dq tentative
and DAD will be performed when this flag is cleared.
.It Cm -ifdisabled
Clear a flag
.Cm ifdisabled .
When this flag is cleared and 
.Cm auto_linklocal
flag is enabled, automatic configuration of a link-local address is
performed.
.It Cm nud
Set a flag to enable Neighbor Unreachability Detection.
.It Cm -nud
Clear a flag
.Cm nud .
.It Cm prefer_source
Set a flag to prefer addresses on the interface as candidates of the
source address for outgoing packets.
.It Cm -prefer_source
Clear a flag
.Cm prefer_source .
.El
.Pp
The following parameters are specific to cloning
IEEE 802.11 wireless interfaces with the
.Cm create
request:
.Bl -tag -width indent
.It Cm wlandev Ar device
Use
.Ar device
as the parent for the cloned device.
.It Cm wlanmode Ar mode
Specify the operating mode for this cloned device.
.Ar mode
is one of
.Cm sta ,
.Cm ahdemo 
(or
.Cm adhoc-demo ),
.Cm ibss ,
(or
.Cm adhoc ),
.Cm ap ,
(or
.Cm hostap ),
.Cm wds ,
.Cm tdma ,
.Cm mesh ,
and
.Cm monitor .
The operating mode of a cloned interface cannot be changed.
The
.Cm tdma
mode is actually implemented as an
.Cm adhoc-demo
interface with special properties.
.It Cm wlanbssid Ar bssid
The 802.11 mac address to use for the bssid.
This must be specified at create time for a legacy
.Cm wds
device.
.It Cm wlanaddr Ar address
The local mac address.
If this is not specified then a mac address will automatically be assigned
to the cloned device.
Typically this address is the same as the address of the parent device
but if the
.Cm bssid
parameter is specified then the driver will craft a unique address for
the device (if supported).
.It Cm wdslegacy
Mark a
.Cm wds
device as operating in ``legacy mode''.
Legacy 
.Cm wds
devices have a fixed peer relationship and do not, for example, roam
if their peer stops communicating.
For completeness a Dynamic WDS (DWDS) interface may marked as
.Fl wdslegacy .
.It Cm bssid
Request a unique local mac address for the cloned device.
This is only possible if the device supports multiple mac addresses.
To force use of the parent's mac address use
.Fl bssid .
.It Cm beacons
Mark the cloned interface as depending on hardware support to
track received beacons.
To have beacons tracked in software use
.Fl beacons .
For 
.Cm hostap
mode 
.Fl beacons
can also be used to indicate no beacons should
be transmitted; this can be useful when creating a WDS configuration but
.Cm wds
interfaces can only be created as companions to an access point.
.El
.Pp
The following parameters are specific to IEEE 802.11 wireless interfaces
cloned with a
.Cm create
operation:
.Bl -tag -width indent
.It Cm ampdu
Enable sending and receiving AMPDU frames when using 802.11n (default).
The 802.11n specification states a compliant station must be capable
of receiving AMPDU frames but transmission is optional.
Use
.Fl ampdu
to disable all use of AMPDU with 802.11n.
For testing and/or to work around interoperability problems one can use
.Cm ampdutx
and
.Cm ampdurx
to control use of AMPDU in one direction.
.It Cm ampdudensity Ar density
Set the AMPDU density parameter used when operating with 802.11n.
This parameter controls the inter-packet gap for AMPDU frames.
The sending device normally controls this setting but a receiving station
may request wider gaps.
Legal values for
.Ar density
are 0, .25, .5, 1, 2, 4, 8, and 16 (microseconds).
A value of
.Cm -
is treated the same as 0.
.It Cm ampdulimit Ar limit
Set the limit on packet size for receiving AMPDU frames when operating
with 802.11n.
Legal values for
.Ar limit
are 8192, 16384, 32768, and 65536 but one can also specify
just the unique prefix: 8, 16, 32, 64.
Note the sender may limit the size of AMPDU frames to be less
than the maximum specified by the receiving station.
.It Cm amsdu
Enable sending and receiving AMSDU frames when using 802.11n.
By default AMSDU is received but not transmitted.
Use
.Fl amsdu
to disable all use of AMSDU with 802.11n.
For testing and/or to work around interoperability problems one can use
.Cm amsdutx
and
.Cm amsdurx
to control use of AMSDU in one direction.
.It Cm amsdulimit Ar limit
Set the limit on packet size for sending and receiving AMSDU frames
when operating with 802.11n.
Legal values for
.Ar limit
are 7935 and 3839 (bytes).
Note the sender may limit the size of AMSDU frames to be less
than the maximum specified by the receiving station.
Note also that devices are not required to support the 7935 limit,
only 3839 is required by the specification and the larger value
may require more memory to be dedicated to support functionality
that is rarely used.
.It Cm apbridge
When operating as an access point, pass packets between
wireless clients directly (default).
To instead let them pass up through the
system and be forwarded using some other mechanism, use
.Fl apbridge .
Disabling the internal bridging
is useful when traffic is to be processed with
packet filtering.
.It Cm authmode Ar mode
Set the desired authentication mode in infrastructure mode.
Not all adapters support all modes.
The set of
valid modes is
.Cm none , open , shared
(shared key),
.Cm 8021x
(IEEE 802.1x),
and
.Cm wpa
(IEEE WPA/WPA2/802.11i).
The
.Cm 8021x
and
.Cm wpa
modes are only useful when using an authentication service
(a supplicant for client operation or an authenticator when
operating as an access point).
Modes are case insensitive.
.It Cm bgscan
Enable background scanning when operating as a station.
Background scanning is a technique whereby a station associated to
an access point will temporarily leave the channel to scan for
neighboring stations.
This allows a station to maintain a cache of nearby access points
so that roaming between access points can be done without
a lengthy scan operation.
Background scanning is done only when a station is not busy and
any outbound traffic will cancel a scan operation.
Background scanning should never cause packets to be lost though
there may be some small latency if outbound traffic interrupts a
scan operation.
By default background scanning is enabled if the device is capable.
To disable background scanning, use
.Fl bgscan .
Background scanning is controlled by the
.Cm bgscanidle
and
.Cm bgscanintvl
parameters.
Background scanning must be enabled for roaming; this is an artifact
of the current implementation and may not be required in the future.
.It Cm bgscanidle Ar idletime
Set the minimum time a station must be idle (not transmitting or
receiving frames) before a background scan is initiated.
The
.Ar idletime
parameter is specified in milliseconds.
By default a station must be idle at least 250 milliseconds before
a background scan is initiated.
The idle time may not be set to less than 100 milliseconds.
.It Cm bgscanintvl Ar interval
Set the interval at which background scanning is attempted.
The
.Ar interval
parameter is specified in seconds.
By default a background scan is considered every 300 seconds (5 minutes).
The 
.Ar interval
may not be set to less than 15 seconds.
.It Cm bintval Ar interval
Set the interval at which beacon frames are sent when operating in
ad-hoc or ap mode.
The
.Ar interval
parameter is specified in TU's (1024 usecs).
By default beacon frames are transmitted every 100 TU's.
.It Cm bmissthreshold Ar count
Set the number of consecutive missed beacons at which the station
will attempt to roam (i.e., search for a new access point).
The
.Ar count
parameter must be in the range 1 to 255; though the
upper bound may be reduced according to device capabilities.
The default threshold is 7 consecutive missed beacons; but
this may be overridden by the device driver.
Another name for the
.Cm bmissthreshold
parameter is
.Cm bmiss .
.It Cm bssid Ar address
Specify the MAC address of the access point to use when operating
as a station in a BSS network.
This overrides any automatic selection done by the system.
To disable a previously selected access point, supply
.Cm any , none ,
or
.Cm -
for the address.
This option is useful when more than one access point uses the same SSID.
Another name for the
.Cm bssid
parameter is
.Cm ap .
.It Cm burst
Enable packet bursting.
Packet bursting is a transmission technique whereby the wireless
medium is acquired once to send multiple frames and the interframe
spacing is reduced.
This technique can significantly increase throughput by reducing
transmission overhead.
Packet bursting is supported by the 802.11e QoS specification
and some devices that do not support QoS may still be capable.
By default packet bursting is enabled if a device is capable
of doing it.
To disable packet bursting, use
.Fl burst .
.It Cm chanlist Ar channels
Set the desired channels to use when scanning for access
points, neighbors in an IBSS network, or looking for unoccupied
channels when operating as an access point.
The set of channels is specified as a comma-separated list with
each element in the list representing either a single channel number or a range
of the form
.Dq Li a-b .
Channel numbers must be in the range 1 to 255 and be permissible
according to the operating characteristics of the device.
.It Cm channel Ar number
Set a single desired channel.
Channels range from 1 to 255, but the exact selection available
depends on the region your adaptor was manufactured for.
Setting
the channel to
.Li any ,
or
.Cm -
will clear any desired channel and, if the device is marked up,
force a scan for a channel to operate on.
Alternatively the frequency, in megahertz, may be specified
instead of the channel number.
.Pp
When there are several ways to use a channel the channel
number/frequency may be appended with attributes to clarify.
For example, if a device is capable of operating on channel 6
with 802.11n and 802.11g then one can specify that g-only use
should be used by specifying ``6:g''.
Similarly the channel width can be specified by appending it
with ``/''; e.g. ``6/40'' specifies a 40MHz wide channel,
These attributes can be combined as in: ``6:ht/40''.
The full set of flags specified following a ``:'' are:
.Cm a
(802.11a),
.Cm b
(802.11b),
.Cm d
(Atheros Dynamic Turbo mode),
.Cm g
(802.11g),
.Cm h
or
.Cm n
(802.11n aka HT),
.Cm s
(Atheros Static Turbo mode),
and
.Cm t
(Atheros Dynamic Turbo mode, or appended to ``st'' and ``dt'').
The full set of channel widths following a '/' are:
.Cm 5 
(5MHz aka quarter-rate channel),
.Cm 10 
(10MHz aka half-rate channel),
.Cm 20 
(20MHz mostly for use in specifying ht20),
and
.Cm 40 
(40MHz mostly for use in specifying ht40).
In addition,
a 40MHz HT channel specification may include the location
of the extension channel by appending ``+'' or ``-'' for above and below,
respectively; e.g. ``2437:ht/40+'' specifies 40MHz wide HT operation 
with the center channel at frequency 2437 and the extension channel above.
.It Cm country Ar name
Set the country code to use in calculating the regulatory constraints
for operation.
In particular the set of available channels, how the wireless device
will operation on the channels, and the maximum transmit power that
can be used on a channel are defined by this setting.
Country/Region codes are specified as a 2-character abbreviation
defined by ISO 3166 or using a longer, but possibly ambiguous, spelling;
e.g. "ES" and "Spain".
The set of country codes are taken from /etc/regdomain.xml and can also
be viewed with the ``list countries'' request.
Note that not all devices support changing the country code from a default
setting; typically stored in EEPROM.
See also
.Cm regdomain ,
.Cm indoor ,
.Cm outdoor ,
and
.Cm anywhere .
.It Cm dfs
Enable Dynamic Frequency Selection (DFS) as specified in 802.11h.
DFS embodies several facilities including detection of overlapping
radar signals, dynamic transmit power control, and channel selection
according to a least-congested criteria.
DFS support is mandatory for some 5Ghz frequencies in certain
locales (e.g. ETSI).
By default DFS is enabled according to the regulatory definitions
specified in /etc/regdomain.xml and the current country code, regdomain,
and channel.
Note the underlying device (and driver) must support radar detection
for full DFS support to work.
To be fully compliant with the local regulatory agency frequencies that
require DFS should not be used unless it is fully supported.
Use
.Fl dfs
to disable this functionality for testing.
.It Cm dotd
Enable support for the 802.11d specification (default).
When this support is enabled in station mode, beacon frames that advertise
a country code different than the currently configured country code will
cause an event to be dispatched to user applications.
This event can be used by the station to adopt that country code and
operate according to the associated regulatory constraints.
When operating as an access point with 802.11d enabled the beacon and
probe response frames transmitted will advertise the current regulatory
domain settings.
To disable 802.11d use
.Fl dotd .
.It Cm doth
Enable 802.11h support including spectrum management.
When 802.11h is enabled beacon and probe response frames will have
the SpectrumMgt bit set in the capabilities field and
country and power constraint information elements will be present.
802.11h support also includes handling Channel Switch Announcements (CSA)
which are a mechanism to coordinate channel changes by an access point.
By default 802.11h is enabled if the device is capable.
To disable 802.11h use
.Fl doth .
.It Cm deftxkey Ar index
Set the default key to use for transmission.
Typically this is only set when using WEP encryption.
Note that you must set a default transmit key
for the system to know which key to use in encrypting outbound traffic.
The
.Cm weptxkey
is an alias for this request; it is provided for backwards compatibility.
.It Cm dtimperiod Ar period
Set the
DTIM
period for transmitting buffered multicast data frames when
operating in ap mode.
The
.Ar period
specifies the number of beacon intervals between DTIM
and must be in the range 1 to 15.
By default DTIM is 1 (i.e., DTIM occurs at each beacon).
.It Cm dturbo
Enable the use of Atheros Dynamic Turbo mode when communicating with
another Dynamic Turbo-capable station.
Dynamic Turbo mode is an Atheros-specific mechanism by which
stations switch between normal 802.11 operation and a ``boosted''
mode in which a 40MHz wide channel is used for communication.
Stations using Dynamic Turbo mode operate boosted only when the
channel is free of non-dturbo stations; when a non-dturbo station
is identified on the channel all stations will automatically drop
back to normal operation.
By default, Dynamic Turbo mode is not enabled, even if the device is capable.
Note that turbo mode (dynamic or static) is only allowed on some
channels depending on the regulatory constraints; use the
.Cm list chan
command to identify the channels where turbo mode may be used.
To disable Dynamic Turbo mode use
.Fl dturbo .
.It Cm dwds
Enable Dynamic WDS (DWDS) support.
DWDS is a facility by which 4-address traffic can be carried between
stations operating in infrastructure mode.
A station first associates to an access point and authenticates using
normal procedures (e.g. WPA).
Then 4-address frames are passed to carry traffic for stations
operating on either side of the wireless link.
DWDS extends the normal WDS mechanism by leveraging existing security
protocols and eliminating static binding.
.Pp
When DWDS is enabled on an access point 4-address frames received from
an authorized station will generate a ``DWDS discovery'' event to user
applications.
This event should be used to create a WDS interface that is bound
to the remote station (and usually plumbed into a bridge).
Once the WDS interface is up and running 4-address traffic then logically
flows through that interface.
.Pp
When DWDS is enabled on a station, traffic with a destination address
different from the peer station are encapsulated in a 4-address frame
and transmitted to the peer.
All 4-address traffic uses the security information of the stations
(e.g. cryptographic keys).
A station is associated using 802.11n facilities may transport
4-address traffic using these same mechanisms; this depends on available
resources and capabilities of the device.
The DWDS implementation guards against layer 2 routing loops of
multicast traffic.
.It Cm ff
Enable the use of Atheros Fast Frames when communicating with
another Fast Frames-capable station.
Fast Frames are an encapsulation technique by which two 802.3
frames are transmitted in a single 802.11 frame.
This can noticeably improve throughput but requires that the
receiving station understand how to decapsulate the frame.
Fast frame use is negotiated using the Atheros 802.11 vendor-specific
protocol extension so enabling use is safe when communicating with
non-Atheros devices.
By default, use of fast frames is enabled if the device is capable.
To explicitly disable fast frames, use
.Fl ff .
.It Cm fragthreshold Ar length
Set the threshold for which transmitted frames are broken into fragments.
The
.Ar length
argument is the frame size in bytes and must be in the range 256 to 2346.
Setting
.Ar length
to
.Li 2346 ,
.Cm any ,
or
.Cm -
disables transmit fragmentation.
Not all adapters honor the fragmentation threshold.
.It Cm hidessid
When operating as an access point, do not broadcast the SSID
in beacon frames or respond to probe request frames unless
they are directed to the ap (i.e., they include the ap's SSID).
By default, the SSID is included in beacon frames and
undirected probe request frames are answered.
To re-enable the broadcast of the SSID etc., use
.Fl hidessid .
.It Cm ht
Enable use of High Throughput (HT) when using 802.11n (default).
The 802.11n specification includes mechanisms for operation
on 20MHz and 40MHz wide channels using different signalling mechanisms
than specified in 802.11b, 802.11g, and 802.11a.
Stations negotiate use of these facilities, termed HT20 and HT40,
when they associate.
To disable all use of 802.11n use
.Fl ht .
To disable use of HT20 (e.g. to force only HT40 use) use
.Fl ht20 .
To disable use of HT40 use
.Fl ht40 .
.Pp
HT configuration is used to ``auto promote'' operation
when several choices are available.
For example, if a station associates to an 11n-capable access point
it controls whether the station uses legacy operation, HT20, or HT40.
When an 11n-capable device is setup as an access point and
Auto Channel Selection is used to locate a channel to operate on,
HT configuration controls whether legacy, HT20, or HT40 operation is setup
on the selected channel.
If a fixed channel is specified for a station then HT configuration can
be given as part of the channel specification; e.g. 6:ht/20 to setup
HT20 operation on channel 6.
.It Cm htcompat
Enable use of compatibility support for pre-802.11n devices (default).
The 802.11n protocol specification went through several incompatible iterations.
Some vendors implemented 11n support to older specifications that
will not interoperate with a purely 11n-compliant station.
In particular the information elements included in management frames
for old devices are different.
When compatibility support is enabled both standard and compatible data
will be provided.
Stations that associate using the compatibility mechanisms are flagged
in ``list sta''.
To disable compatibility support use
.Fl htcompat .
.It Cm htprotmode Ar technique
For interfaces operating in 802.11n, use the specified
.Ar technique
for protecting HT frames in a mixed legacy/HT network.
The set of valid techniques is
.Cm off ,
and
.Cm rts
(RTS/CTS, default).
Technique names are case insensitive.
.It Cm inact
Enable inactivity processing for stations associated to an
access point (default).
When operating as an access point the 802.11 layer monitors
the activity of each associated station.
When a station is inactive for 5 minutes it will send several
``probe frames'' to see if the station is still present.
If no response is received then the station is deauthenticated.
Applications that prefer to handle this work can disable this
facility by using
.Fl inact .
.It Cm indoor
Set the location to use in calculating regulatory constraints.
The location is also advertised in beacon and probe response frames
when 802.11d is enabled with
.Cm dotd .
See also
.Cm outdoor ,
.Cm anywhere ,
.Cm country ,
and
.Cm regdomain .
.It Cm list active
Display the list of channels available for use taking into account
any restrictions set with the
.Cm chanlist
directive.
See the description of
.Cm list chan
for more information.
.It Cm list caps
Display the adaptor's capabilities, including the operating
modes supported.
.It Cm list chan
Display the list of channels available for use.
Channels are shown with their IEEE channel number, equivalent
frequency, and usage modes.
Channels identified as
.Ql 11g
are also usable in
.Ql 11b
mode.
Channels identified as
.Ql 11a Turbo
may be used only for Atheros' Static Turbo mode
(specified with
. Cm mediaopt turbo ) .
Channels marked with a
.Ql *
have a regulatory constraint that they be passively scanned.
This means a station is not permitted to transmit on the channel until
it identifies the channel is being used for 802.11 communication;
typically by hearing a beacon frame from an access point operating
on the channel.
.Cm list freq
is another way of requesting this information.
By default a compacted list of channels is displayed; if the
.Fl v
option is specified then all channels are shown.
.It Cm list countries
Display the set of country codes and regulatory domains that can be
used in regulatory configuration.
.It Cm list mac
Display the current MAC Access Control List state.
Each address is prefixed with a character that indicates the
current policy applied to it:
.Ql +
indicates the address is allowed access,
.Ql -
indicates the address is denied access,
.Ql *
indicates the address is present but the current policy open
(so the ACL is not consulted).
.It Cm list mesh
Displays the mesh routing table, used for forwarding packets on a mesh
network.
.It Cm list regdomain
Display the current regulatory settings including the available channels
and transmit power caps.
.It Cm list roam
Display the parameters that govern roaming operation.
.It Cm list txparam
Display the parameters that govern transmit operation.
.It Cm list txpower
Display the transmit power caps for each channel.
.It Cm list scan
Display the access points and/or ad-hoc neighbors
located in the vicinity.
This information may be updated automatically by the adapter
with a
.Cm scan
request or through background scanning.
Depending on the capabilities of the stations the following
flags can be included in the output:
.Bl -tag -width 3n
.It Li A
Authorized.
Indicates that the station is permitted to send/receive data frames.
.It Li E
Extended Rate Phy (ERP).
Indicates that the station is operating in an 802.11g network
using extended transmit rates.
.It Li H
High Throughput (HT).
Indicates that the station is using HT transmit rates.
If a `+' follows immediately after then the station associated
using deprecated mechanisms supported only when
.Cm htcompat
is enabled.
.It Li P
Power Save.
Indicates that the station is operating in power save mode.
.It Li Q
Quality of Service (QoS).
Indicates that the station is using QoS encapsulation for
data frame.
QoS encapsulation is enabled only when WME mode is enabled.
.It Li S
Short Preamble.
Indicates that the station is doing short preamble to optionally
improve throughput performance with 802.11g and 802.11b.
.It Li T
Transitional Security Network (TSN).
Indicates that the station associated using TSN; see also
.Cm tsn
below.
.It Li W
Wi-Fi Protected Setup (WPS).
Indicates that the station associated using WPS.
.El
.Pp
By default interesting information elements captured from the neighboring
stations are displayed at the end of each row.
Possible elements include:
.Cm WME
(station supports WME),
.Cm WPA
(station supports WPA),
.Cm WPS
(station supports WPS),
.Cm RSN
(station supports 802.11i/RSN),
.Cm HTCAP
(station supports 802.11n/HT communication),
.Cm ATH
(station supports Atheros protocol extensions),
.Cm VEN
(station supports unknown vendor-specific extensions).
If the
.Fl v
flag is used all the information elements and their
contents will be shown.
Specifying the
.Fl v
flag also enables display of long SSIDs.
The
.Cm list ap
command is another way of requesting this information.
.It Cm list sta
When operating as an access point display the stations that are
currently associated.
When operating in ad-hoc mode display stations identified as
neighbors in the IBSS.
When operating in mesh mode display stations identified as
neighbors in the MBSS.
When operating in station mode display the access point.
Capabilities advertised by the stations are described under
the
.Cm scan
request.
Depending on the capabilities of the stations the following
flags can be included in the output:
.Bl -tag -width 3n
.It Li A
Authorized.
Indicates that the station is permitted to send/receive data frames.
.It Li E
Extended Rate Phy (ERP).
Indicates that the station is operating in an 802.11g network
using extended transmit rates.
.It Li H
High Throughput (HT).
Indicates that the station is using HT transmit rates.
If a `+' follows immediately after then the station associated
using deprecated mechanisms supported only when
.Cm htcompat
is enabled.
.It Li P
Power Save.
Indicates that the station is operating in power save mode.
.It Li Q
Quality of Service (QoS).
Indicates that the station is using QoS encapsulation for
data frame.
QoS encapsulation is enabled only when WME mode is enabled.
.It Li S
Short Preamble.
Indicates that the station is doing short preamble to optionally
improve throughput performance with 802.11g and 802.11b.
.It Li T
Transitional Security Network (TSN).
Indicates that the station associated using TSN; see also
.Cm tsn
below.
.It Li W
Wi-Fi Protected Setup (WPS).
Indicates that the station associated using WPS.
.El
.Pp
By default information elements received from associated stations
are displayed in a short form; the
.Fl v
flag causes this information to be displayed symbolically.
.It Cm list wme
Display the current channel parameters to use when operating in WME mode.
If the
.Fl v
option is specified then both channel and BSS parameters are displayed
for each AC (first channel, then BSS).
When WME mode is enabled for an adaptor this information will be
displayed with the regular status; this command is mostly useful
for examining parameters when WME mode is disabled.
See the description of the
.Cm wme
directive for information on the various parameters.
.It Cm maxretry Ar count
Set the maximum number of tries to use in sending unicast frames.
The default setting is 6 but drivers may override this with a value
they choose.
.It Cm mcastrate Ar rate
Set the rate for transmitting multicast/broadcast frames.
Rates are specified as megabits/second in decimal; e.g.\& 5.5 for 5.5 Mb/s.
This rate should be valid for the current operating conditions;
if an invalid rate is specified drivers are free to chose an
appropriate rate.
.It Cm mgtrate Ar rate
Set the rate for transmitting management and/or control frames.
Rates are specified as megabits/second in decimal; e.g.\& 5.5 for 5.5 Mb/s.
.It Cm outdoor
Set the location to use in calculating regulatory constraints.
The location is also advertised in beacon and probe response frames
when 802.11d is enabled with
.Cm dotd .
See also
.Cm anywhere ,
.Cm country ,
.Cm indoor ,
and
.Cm regdomain .
.It Cm powersave
Enable powersave operation.
When operating as a client, the station will conserve power by
periodically turning off the radio and listening for
messages from the access point telling it there are packets waiting.
The station must then retrieve the packets.
Not all devices support power save operation as a client.
The 802.11 specification requires that all access points support
power save but some drivers do not.
Use
.Fl powersave
to disable powersave operation when operating as a client.
.It Cm powersavesleep Ar sleep
Set the desired max powersave sleep time in TU's (1024 usecs).
By default the max powersave sleep time is 100 TU's.
.It Cm protmode Ar technique
For interfaces operating in 802.11g, use the specified
.Ar technique
for protecting OFDM frames in a mixed 11b/11g network.
The set of valid techniques is
.Cm off , cts
(CTS to self),
and
.Cm rtscts
(RTS/CTS).
Technique names are case insensitive.
Not all devices support
.Cm cts
as a protection technique.
.It Cm pureg
When operating as an access point in 802.11g mode allow only
11g-capable stations to associate (11b-only stations are not
permitted to associate).
To allow both 11g and 11b-only stations to associate, use
.Fl pureg .
.It Cm puren
When operating as an access point in 802.11n mode allow only
HT-capable stations to associate (legacy stations are not
permitted to associate).
To allow both HT and legacy stations to associate, use
.Fl puren .
.It Cm regdomain Ar sku
Set the regulatory domain to use in calculating the regulatory constraints
for operation.
In particular the set of available channels, how the wireless device
will operation on the channels, and the maximum transmit power that
can be used on a channel are defined by this setting.
Regdomain codes (SKU's) are taken from /etc/regdomain.xml and can also
be viewed with the ``list countries'' request.
Note that not all devices support changing the regdomain from a default
setting; typically stored in EEPROM.
See also
.Cm country ,
.Cm indoor ,
.Cm outdoor ,
and
.Cm anywhere .
.It Cm rifs
Enable use of Reduced InterFrame Spacing (RIFS) when operating in 802.11n
on an HT channel.
Note that RIFS must be supported by both the station and access point
for it to be used.
To disable RIFS use
.Fl rifs .
.It Cm roam:rate Ar rate
Set the threshold for controlling roaming when operating in a BSS.
The
.Ar rate
parameter specifies the transmit rate in megabits
at which roaming should be considered.
If the current transmit rate drops below this setting and background scanning
is enabled, then the system will check if a more desirable access point is
available and switch over to it.
The current scan cache contents are used if they are considered
valid according to the
.Cm scanvalid
parameter; otherwise a background scan operation is triggered before
any selection occurs.
Each channel type has a separate rate threshold; the default values are:
12 Mb/s (11a), 2 Mb/s (11b), 2 Mb/s (11g), MCS 1 (11na, 11ng).
.It Cm roam:rssi Ar rssi
Set the threshold for controlling roaming when operating in a BSS.
The
.Ar rssi
parameter specifies the receive signal strength in dBm units
at which roaming should be considered.
If the current rssi drops below this setting and background scanning
is enabled, then the system will check if a more desirable access point is
available and switch over to it.
The current scan cache contents are used if they are considered
valid according to the
.Cm scanvalid
parameter; otherwise a background scan operation is triggered before
any selection occurs.
Each channel type has a separate rssi threshold; the default values are
all 7 dBm.
.It Cm roaming Ar mode
When operating as a station, control how the system will
behave when communication with the current access point
is broken.
The
.Ar mode
argument may be one of
.Cm device
(leave it to the hardware device to decide),
.Cm auto
(handle either in the device or the operating system\[em]as appropriate),
.Cm manual
(do nothing until explicitly instructed).
By default, the device is left to handle this if it is
capable; otherwise, the operating system will automatically
attempt to reestablish communication.
Manual mode is used by applications such as
.Xr wpa_supplicant 8
that want to control the selection of an access point.
.It Cm rtsthreshold Ar length
Set the threshold for which
transmitted frames are preceded by transmission of an
RTS
control frame.
The
.Ar length
argument
is the frame size in bytes and must be in the range 1 to 2346.
Setting
.Ar length
to
.Li 2346 ,
.Cm any ,
or
.Cm -
disables transmission of RTS frames.
Not all adapters support setting the RTS threshold.
.It Cm scan
Initiate a scan of neighboring stations, wait for it to complete, and
display all stations found.
Only the super-user can initiate a scan.
See
.Cm list scan
for information on the display.
By default a background scan is done; otherwise a foreground
scan is done and the station may roam to a different access point.
The
.Cm list scan
request can be used to show recent scan results without
initiating a new scan.
.It Cm scanvalid Ar threshold
Set the maximum time the scan cache contents are considered valid;
i.e. will be used without first triggering a scan operation to
refresh the data.
The
.Ar threshold
parameter is specified in seconds and defaults to 60 seconds.
The minimum setting for
.Ar threshold
is 10 seconds.
One should take care setting this threshold; if it is set too low
then attempts to roam to another access point may trigger unnecessary
background scan operations.
.It Cm shortgi
Enable use of Short Guard Interval when operating in 802.11n
on an HT channel.
NB: this currently enables Short GI on both HT40 and HT20 channels.
To disable Short GI use
.Fl shortgi .
.It Cm smps
Enable use of Static Spatial Multiplexing Power Save (SMPS)
when operating in 802.11n.
A station operating with Static SMPS maintains only a single
receive chain active (this can significantly reduce power consumption).
To disable SMPS use
.Fl smps .
.It Cm smpsdyn
Enable use of Dynamic Spatial Multiplexing Power Save (SMPS)
when operating in 802.11n.
A station operating with Dynamic SMPS maintains only a single
receive chain active but switches to multiple receive chains when it
receives an RTS frame (this can significantly reduce power consumption).
Note that stations cannot distinguish between RTS/CTS intended to
enable multiple receive chains and those used for other purposes.
To disable SMPS use
.Fl smps .
.It Cm ssid Ar ssid
Set the desired Service Set Identifier (aka network name).
The SSID is a string up to 32 characters
in length and may be specified as either a normal string or in
hexadecimal when preceded by
.Ql 0x .
Additionally, the SSID may be cleared by setting it to
.Ql - .
.It Cm tdmaslot Ar slot
When operating with TDMA, use the specified
.Ar slot
configuration.
The
.Ar slot
is a number between 0 and the maximum number of slots in the BSS.
Note that a station configured as slot 0 is a master and
will broadcast beacon frames advertising the BSS;
stations configured to use other slots will always
scan to locate a master before they ever transmit.
By default
.Cm tdmaslot
is set to 1.
.It Cm tdmaslotcnt Ar cnt
When operating with TDMA, setup a BSS with
.Ar cnt
slots.
The slot count may be at most 8.
The current implementation is only tested with two stations
(i.e. point to point applications).
This setting is only meaningful when a station is configured as slot 0;
other stations adopt this setting from the BSS they join.
By default
.Cm tdmaslotcnt
is set to 2.
.It Cm tdmaslotlen Ar len
When operating with TDMA, setup a BSS such that each station has a slot
.Ar len
microseconds long.
The slot length must be at least 150 microseconds (1/8 TU)
and no more than 65 milliseconds.
Note that setting too small a slot length may result in poor channel
bandwidth utilization due to factors such as timer granularity and
guard time.
This setting is only meaningful when a station is configured as slot 0;
other stations adopt this setting from the BSS they join.
By default
.Cm tdmaslotlen
is set to 10 milliseconds.
.It Cm tdmabintval Ar intval
When operating with TDMA, setup a BSS such that beacons are transmitted every
.Ar intval
superframes to synchronize the TDMA slot timing.
A superframe is defined as the number of slots times the slot length; e.g.
a BSS with two slots of 10 milliseconds has a 20 millisecond superframe.
The beacon interval may not be zero.
A lower setting of
.Cm tdmabintval
causes the timers to be resynchronized more often; this can be help if
significant timer drift is observed.
By default
.Cm tdmabintval
is set to 5.
.It Cm tsn
When operating as an access point with WPA/802.11i allow legacy
stations to associate using static key WEP and open authentication.
To disallow legacy station use of WEP, use
.Fl tsn .
.It Cm txpower Ar power
Set the power used to transmit frames.
The
.Ar power
argument is specified in .5 dBm units.
Out of range values are truncated.
Typically only a few discreet power settings are available and
the driver will use the setting closest to the specified value.
Not all adapters support changing the transmit power.
.It Cm ucastrate Ar rate
Set a fixed rate for transmitting unicast frames.
Rates are specified as megabits/second in decimal; e.g.\& 5.5 for 5.5 Mb/s.
This rate should be valid for the current operating conditions;
if an invalid rate is specified drivers are free to chose an
appropriate rate.
.It Cm wepmode Ar mode
Set the desired WEP mode.
Not all adapters support all modes.
The set of valid modes is
.Cm off , on ,
and
.Cm mixed .
The
.Cm mixed
mode explicitly tells the adaptor to allow association with access
points which allow both encrypted and unencrypted traffic.
On these adapters,
.Cm on
means that the access point must only allow encrypted connections.
On other adapters,
.Cm on
is generally another name for
.Cm mixed .
Modes are case insensitive.
.It Cm weptxkey Ar index
Set the WEP key to be used for transmission.
This is the same as setting the default transmission key with
.Cm deftxkey .
.It Cm wepkey Ar key Ns | Ns Ar index : Ns Ar key
Set the selected WEP key.
If an
.Ar index
is not given, key 1 is set.
A WEP key will be either 5 or 13
characters (40 or 104 bits) depending on the local network and the
capabilities of the adaptor.
It may be specified either as a plain
string or as a string of hexadecimal digits preceded by
.Ql 0x .
For maximum portability, hex keys are recommended;
the mapping of text keys to WEP encryption is usually driver-specific.
In particular, the
.Tn Windows
drivers do this mapping differently to
.Fx .
A key may be cleared by setting it to
.Ql - .
If WEP is supported then there are at least four keys.
Some adapters support more than four keys.
If that is the case, then the first four keys
(1-4) will be the standard temporary keys and any others will be adaptor
specific keys such as permanent keys stored in NVRAM.
.Pp
Note that you must set a default transmit key with
.Cm deftxkey
for the system to know which key to use in encrypting outbound traffic.
.It Cm wme
Enable Wireless Multimedia Extensions (WME) support, if available,
for the specified interface.
WME is a subset of the IEEE 802.11e standard to support the
efficient communication of realtime and multimedia data.
To disable WME support, use
.Fl wme .
Another name for this parameter is
.Cm wmm .
.Pp
The following parameters are meaningful only when WME support is in use.
Parameters are specified per-AC (Access Category) and
split into those that are used by a station when acting
as an access point and those for client stations in the BSS.
The latter are received from the access point and may not be changed
(at the station).
The following Access Categories are recognized:
.Pp
.Bl -tag -width ".Cm AC_BK" -compact
.It Cm AC_BE
(or
.Cm BE )
best effort delivery,
.It Cm AC_BK
(or
.Cm BK )
background traffic,
.It Cm AC_VI
(or
.Cm VI )
video traffic,
.It Cm AC_VO
(or
.Cm VO )
voice traffic.
.El
.Pp
AC parameters are case-insensitive.
Traffic classification is done in the operating system using the
vlan priority associated with data frames or the
ToS (Type of Service) indication in IP-encapsulated frames.
If neither information is present, traffic is assigned to the
Best Effort (BE) category.
.Bl -tag -width indent
.It Cm ack Ar ac
Set the ACK policy for QoS transmissions by the local station;
this controls whether or not data frames transmitted by a station
require an ACK response from the receiving station.
To disable waiting for an ACK use
.Fl ack .
This parameter is applied only to the local station.
.It Cm acm Ar ac
Enable the Admission Control Mandatory (ACM) mechanism
for transmissions by the local station.
To disable the ACM use
.Fl acm .
On stations in a BSS this parameter is read-only and indicates
the setting received from the access point.
NB: ACM is not supported right now.
.It Cm aifs Ar ac Ar count
Set the Arbitration Inter Frame Spacing (AIFS)
channel access parameter to use for transmissions
by the local station.
On stations in a BSS this parameter is read-only and indicates
the setting received from the access point.
.It Cm cwmin Ar ac Ar count
Set the CWmin channel access parameter to use for transmissions
by the local station.
On stations in a BSS this parameter is read-only and indicates
the setting received from the access point.
.It Cm cwmax Ar ac Ar count
Set the CWmax channel access parameter to use for transmissions
by the local station.
On stations in a BSS this parameter is read-only and indicates
the setting received from the access point.
.It Cm txoplimit Ar ac Ar limit
Set the Transmission Opportunity Limit channel access parameter
to use for transmissions by the local station.
This parameter defines an interval of time when a WME station
has the right to initiate transmissions onto the wireless medium.
On stations in a BSS this parameter is read-only and indicates
the setting received from the access point.
.It Cm bss:aifs Ar ac Ar count
Set the AIFS channel access parameter to send to stations in a BSS.
This parameter is meaningful only when operating in ap mode.
.It Cm bss:cwmin Ar ac Ar count
Set the CWmin channel access parameter to send to stations in a BSS.
This parameter is meaningful only when operating in ap mode.
.It Cm bss:cwmax Ar ac Ar count
Set the CWmax channel access parameter to send to stations in a BSS.
This parameter is meaningful only when operating in ap mode.
.It Cm bss:txoplimit Ar ac Ar limit
Set the TxOpLimit channel access parameter to send to stations in a BSS.
This parameter is meaningful only when operating in ap mode.
.El
.It Cm wps
Enable Wireless Privacy Subscriber support.
Note that WPS support requires a WPS-capable supplicant.
To disable this function use
.Fl wps .
.El
.Pp
The following parameters support an optional access control list
feature available with some adapters when operating in ap mode; see
.Xr wlan_acl 4 .
This facility allows an access point to accept/deny association
requests based on the MAC address of the station.
Note that this feature does not significantly enhance security
as MAC address spoofing is easy to do.
.Bl -tag -width indent
.It Cm mac:add Ar address
Add the specified MAC address to the database.
Depending on the policy setting association requests from the
specified station will be allowed or denied.
.It Cm mac:allow
Set the ACL policy to permit association only by
stations registered in the database.
.It Cm mac:del Ar address
Delete the specified MAC address from the database.
.It Cm mac:deny
Set the ACL policy to deny association only by
stations registered in the database.
.It Cm mac:kick Ar address
Force the specified station to be deauthenticated.
This typically is done to block a station after updating the
address database.
.It Cm mac:open
Set the ACL policy to allow all stations to associate.
.It Cm mac:flush
Delete all entries in the database.
.It Cm mac:radius
Set the ACL policy to permit association only by
stations approved by a RADIUS server.
Note that this feature requires the
.Xr hostapd 8
program be configured to do the right thing
as it handles the RADIUS processing
(and marks stations as authorized).
.El
.Pp
The following parameters are related to a wireless interface operating in mesh
mode:
.Bl -tag -width indent
.It Cm meshid Ar meshid
Set the desired Mesh Identifier.
The Mesh ID is a string up to 32 characters in length.
A mesh interface must have a Mesh Identifier specified
to reach an operational state.
.It Cm meshttl Ar ttl
Set the desired ``time to live'' for mesh forwarded packets;
this is the number of hops a packet may be forwarded before
it is discarded.
The default setting for
.Cm meshttl
is 31.
.It Cm meshpeering
Enable or disable peering with neighbor mesh stations.
Stations must peer before any data packets can be exchanged.
By default
.Cm meshpeering
is enabled.
.It Cm meshforward
Enable or disable forwarding packets by a mesh interface.
By default
.Cm meshforward
is enabled.
.It Cm meshmetric Ar protocol
Set the specified
.Ar protocol
as the link metric protocol used on a mesh network.
The default protocol is called
.Ar AIRTIME .
The mesh interface will restart after changing this setting.
.It Cm meshpath Ar protocol
Set the specified
.Ar protocol
as the path selection protocol used on a mesh network.
The only available protocol at the moment is called
.Ar HWMP
(Hybrid Wireless Mesh Protocol).
The mesh interface will restart after changing this setting.
.It Cm hwmprootmode Ar mode
Stations on a mesh network can operate as ``root nodes.''
Root nodes try to find paths to all mesh nodes and advertise themselves
regularly.
When there is a root mesh node on a network, other mesh nodes can setup
paths between themselves faster because they can use the root node
to find the destination.
This path may not be the best, but on-demand
routing will eventually find the best path.
The following modes are recognized:
.Pp
.Bl -tag -width ".Cm PROACTIVE" -compact
.It Cm DISABLED
Disable root mode.
.It Cm NORMAL
Send broadcast path requests every two seconds.
Nodes on the mesh without a path to this root mesh station with try to
discover a path to us.
.It Cm PROACTIVE
Send broadcast path requests every two seconds and every node must reply with
with a path reply even if it already has a path to this root mesh station.
.It Cm RANN
Send broadcast root announcement (RANN) frames.
Nodes on the mesh without a path to this root mesh station with try to
discover a path to us.
.El
By default
.Cm hwmprootmode 
is set to
.Ar DISABLED .
.It Cm hwmpmaxhops Ar cnt
Set the maximum number of hops allowed in an HMWP path to
.Ar cnt .
The default setting for
.Cm hwmpmaxhops
is 31.
.El
.Pp
The following parameters are for compatibility with other systems:
.Bl -tag -width indent
.It Cm nwid Ar ssid
Another name for the
.Cm ssid
parameter.
Included for
.Nx
compatibility.
.It Cm stationname Ar name
Set the name of this station.
The station name is not part of the IEEE 802.11
protocol though some interfaces support it.
As such it only
seems to be meaningful to identical or virtually identical equipment.
Setting the station name is identical in syntax to setting the SSID.
One can also use
.Cm station
for
.Bsx
compatibility.
.It Cm wep
Another way of saying
.Cm wepmode on .
Included for
.Bsx
compatibility.
.It Fl wep
Another way of saying
.Cm wepmode off .
Included for
.Bsx
compatibility.
.It Cm nwkey key
Another way of saying:
.Dq Li "wepmode on weptxkey 1 wepkey 1:key wepkey 2:- wepkey 3:- wepkey 4:-" .
Included for
.Nx
compatibility.
.It Cm nwkey Xo
.Sm off
.Ar n : k1 , k2 , k3 , k4
.Sm on
.Xc
Another way of saying
.Dq Li "wepmode on weptxkey n wepkey 1:k1 wepkey 2:k2 wepkey 3:k3 wepkey 4:k4" .
Included for
.Nx
compatibility.
.It Fl nwkey
Another way of saying
.Cm wepmode off .
Included for
.Nx
compatibility.
.El
.Pp
The following parameters are specific to bridge interfaces:
.Bl -tag -width indent
.It Cm addm Ar interface
Add the interface named by
.Ar interface
as a member of the bridge.
The interface is put into promiscuous mode
so that it can receive every packet sent on the network.
.It Cm deletem Ar interface
Remove the interface named by
.Ar interface
from the bridge.
Promiscuous mode is disabled on the interface when
it is removed from the bridge.
.It Cm maxaddr Ar size
Set the size of the bridge address cache to
.Ar size .
The default is 100 entries.
.It Cm timeout Ar seconds
Set the timeout of address cache entries to
.Ar seconds
seconds.
If
.Ar seconds
is zero, then address cache entries will not be expired.
The default is 240 seconds.
.It Cm addr
Display the addresses that have been learned by the bridge.
.It Cm static Ar interface-name Ar address
Add a static entry into the address cache pointing to
.Ar interface-name .
Static entries are never aged out of the cache or re-placed, even if the
address is seen on a different interface.
.It Cm deladdr Ar address
Delete
.Ar address
from the address cache.
.It Cm flush
Delete all dynamically-learned addresses from the address cache.
.It Cm flushall
Delete all addresses, including static addresses, from the address cache.
.It Cm discover Ar interface
Mark an interface as a
.Dq discovering
interface.
When the bridge has no address cache entry
(either dynamic or static)
for the destination address of a packet,
the bridge will forward the packet to all
member interfaces marked as
.Dq discovering .
This is the default for all interfaces added to a bridge.
.It Cm -discover Ar interface
Clear the
.Dq discovering
attribute on a member interface.
For packets without the
.Dq discovering
attribute, the only packets forwarded on the interface are broadcast
or multicast packets and packets for which the destination address
is known to be on the interface's segment.
.It Cm learn Ar interface
Mark an interface as a
.Dq learning
interface.
When a packet arrives on such an interface, the source
address of the packet is entered into the address cache as being a
destination address on the interface's segment.
This is the default for all interfaces added to a bridge.
.It Cm -learn Ar interface
Clear the
.Dq learning
attribute on a member interface.
.It Cm sticky Ar interface
Mark an interface as a
.Dq sticky
interface.
Dynamically learned address entries are treated at static once entered into
the cache.
Sticky entries are never aged out of the cache or replaced, even if the
address is seen on a different interface.
.It Cm -sticky Ar interface
Clear the
.Dq sticky
attribute on a member interface.
.It Cm private Ar interface
Mark an interface as a
.Dq private
interface.
A private interface does not forward any traffic to any other port that is also
a private interface.
.It Cm -private Ar interface
Clear the
.Dq private
attribute on a member interface.
.It Cm span Ar interface
Add the interface named by
.Ar interface
as a span port on the bridge.
Span ports transmit a copy of every frame received by the bridge.
This is most useful for snooping a bridged network passively on
another host connected to one of the span ports of the bridge.
.It Cm -span Ar interface
Delete the interface named by
.Ar interface
from the list of span ports of the bridge.
.It Cm stp Ar interface
Enable Spanning Tree protocol on
.Ar interface .
The
.Xr if_bridge 4
driver has support for the IEEE 802.1D Spanning Tree protocol (STP).
Spanning Tree is used to detect and remove loops in a network topology.
.It Cm -stp Ar interface
Disable Spanning Tree protocol on
.Ar interface .
This is the default for all interfaces added to a bridge.
.It Cm edge Ar interface
Set
.Ar interface
as an edge port.
An edge port connects directly to end stations cannot create bridging
loops in the network, this allows it to transition straight to forwarding.
.It Cm -edge Ar interface
Disable edge status on
.Ar interface .
.It Cm autoedge Ar interface
Allow
.Ar interface
to automatically detect edge status.
This is the default for all interfaces added to a bridge.
.It Cm -autoedge Ar interface
Disable automatic edge status on
.Ar interface .
.It Cm ptp Ar interface
Set the
.Ar interface
as a point to point link.
This is required for straight transitions to forwarding and
should be enabled on a direct link to another RSTP capable switch.
.It Cm -ptp Ar interface
Disable point to point link status on
.Ar interface .
This should be disabled for a half duplex link and for an interface
connected to a shared network segment,
like a hub or a wireless network.
.It Cm autoptp Ar interface
Automatically detect the point to point status on
.Ar interface
by checking the full duplex link status.
This is the default for interfaces added to the bridge.
.It Cm -autoptp Ar interface
Disable automatic point to point link detection on
.Ar interface .
.It Cm maxage Ar seconds
Set the time that a Spanning Tree protocol configuration is valid.
The default is 20 seconds.
The minimum is 6 seconds and the maximum is 40 seconds.
.It Cm fwddelay Ar seconds
Set the time that must pass before an interface begins forwarding
packets when Spanning Tree is enabled.
The default is 15 seconds.
The minimum is 4 seconds and the maximum is 30 seconds.
.It Cm hellotime Ar seconds
Set the time between broadcasting of Spanning Tree protocol
configuration messages.
The hello time may only be changed when operating in legacy stp mode.
The default is 2 seconds.
The minimum is 1 second and the maximum is 2 seconds.
.It Cm priority Ar value
Set the bridge priority for Spanning Tree.
The default is 32768.
The minimum is 0 and the maximum is 61440.
.It Cm proto Ar value
Set the Spanning Tree protocol.
The default is rstp.
The available options are stp and rstp.
.It Cm holdcnt Ar value
Set the transmit hold count for Spanning Tree.
This is the number of packets transmitted before being rate limited.
The default is 6.
The minimum is 1 and the maximum is 10.
.It Cm ifpriority Ar interface Ar value
Set the Spanning Tree priority of
.Ar interface
to
.Ar value .
The default is 128.
The minimum is 0 and the maximum is 240.
.It Cm ifpathcost Ar interface Ar value
Set the Spanning Tree path cost of
.Ar interface
to
.Ar value .
The default is calculated from the link speed.
To change a previously selected path cost back to automatic, set the
cost to 0.
The minimum is 1 and the maximum is 200000000.
.It Cm ifmaxaddr Ar interface Ar size
Set the maximum number of hosts allowed from an interface, packets with unknown
source addresses are dropped until an existing host cache entry expires or is
removed.
Set to 0 to disable.
.El
.Pp
The following parameters are specific to lagg interfaces:
.Bl -tag -width indent
.It Cm laggport Ar interface
Add the interface named by
.Ar interface
as a port of the aggregation interface.
.It Cm -laggport Ar interface
Remove the interface named by
.Ar interface
from the aggregation interface.
.It Cm laggproto Ar proto
Set the aggregation protocol.
The default is failover.
The available options are failover, fec, lacp, loadbalance, roundrobin and
none.
.El
.Pp
The following parameters are specific to IP tunnel interfaces,
.Xr gif 4 :
.Bl -tag -width indent
.It Cm tunnel Ar src_addr dest_addr
Configure the physical source and destination address for IP tunnel
interfaces.
The arguments
.Ar src_addr
and
.Ar dest_addr
are interpreted as the outer source/destination for the encapsulating
IPv4/IPv6 header.
.It Fl tunnel
Unconfigure the physical source and destination address for IP tunnel
interfaces previously configured with
.Cm tunnel .
.It Cm deletetunnel
Another name for the
.Fl tunnel
parameter.
.It Cm accept_rev_ethip_ver
Set a flag to accept both correct EtherIP packets and ones
with reversed version field.  Enabled by default.
This is for backward compatibility with
.Fx 6.1 ,
6.2, 6.3, 7.0, and 7.1.
.It Cm -accept_rev_ethip_ver
Clear a flag
.Cm accept_rev_ethip_ver .
.It Cm send_rev_ethip_ver
Set a flag to send EtherIP packets with reversed version
field intentionally.  Disabled by default.
This is for backward compatibility with
.Fx 6.1 ,
6.2, 6.3, 7.0, and 7.1.
.It Cm -send_rev_ethip_ver
Clear a flag
.Cm send_rev_ethip_ver .
.El
.Pp
The following parameters are specific to GRE tunnel interfaces,
.Xr gre 4 :
.Bl -tag -width indent
.It Cm grekey Ar key
Configure the GRE key to be used for outgoing packets.
Note that
.Xr gre 4 will always accept GRE packets with invalid or absent keys.
This command will result in a four byte MTU reduction on the interface.
.El
.Pp
The following parameters are specific to
.Xr pfsync 4
interfaces:
.Bl -tag -width indent
.It Cm maxupd Ar n
Set the maximum number of updates for a single state which
can be collapsed into one.
This is an 8-bit number; the default value is 128.
.El
.Pp
The following parameters are specific to
.Xr vlan 4
interfaces:
.Bl -tag -width indent
.It Cm vlan Ar vlan_tag
Set the VLAN tag value to
.Ar vlan_tag .
This value is a 16-bit number which is used to create an 802.1Q
VLAN header for packets sent from the
.Xr vlan 4
interface.
Note that
.Cm vlan
and
.Cm vlandev
must both be set at the same time.
.It Cm vlandev Ar iface
Associate the physical interface
.Ar iface
with a
.Xr vlan 4
interface.
Packets transmitted through the
.Xr vlan 4
interface will be
diverted to the specified physical interface
.Ar iface
with 802.1Q VLAN encapsulation.
Packets with 802.1Q encapsulation received
by the parent interface with the correct VLAN tag will be diverted to
the associated
.Xr vlan 4
pseudo-interface.
The
.Xr vlan 4
interface is assigned a
copy of the parent interface's flags and the parent's ethernet address.
The
.Cm vlandev
and
.Cm vlan
must both be set at the same time.
If the
.Xr vlan 4
interface already has
a physical interface associated with it, this command will fail.
To
change the association to another physical interface, the existing
association must be cleared first.
.Pp
Note: if the hardware tagging capability
is set on the parent interface, the
.Xr vlan 4
pseudo
interface's behavior changes:
the
.Xr vlan 4
interface recognizes that the
parent interface supports insertion and extraction of VLAN tags on its
own (usually in firmware) and that it should pass packets to and from
the parent unaltered.
.It Fl vlandev Op Ar iface
If the driver is a
.Xr vlan 4
pseudo device, disassociate the parent interface from it.
This breaks the link between the
.Xr vlan 4
interface and its parent,
clears its VLAN tag, flags and its link address and shuts the interface down.
The
.Ar iface
argument is useless and hence deprecated.
.El
.Pp
The following parameters are specific to
.Xr carp 4
interfaces:
.Bl -tag -width indent
.It Cm advbase Ar seconds
Specifies the base of the advertisement interval in seconds.
The acceptable values are 1 to 255.
The default value is 1.
.\" The default value is
.\" .Dv CARP_DFLTINTV .
.It Cm advskew Ar interval
Specifies the skew to add to the base advertisement interval to
make one host advertise slower than another host.
It is specified in 1/256 of seconds.
The acceptable values are 1 to 254.
The default value is 0.
.It Cm pass Ar phrase
Set the authentication key to
.Ar phrase .
.It Cm vhid Ar n
Set the virtual host ID.
This is a required setting.
Acceptable values are 1 to 255.
.El
.Pp
The
.Nm
utility displays the current configuration for a network interface
when no optional parameters are supplied.
If a protocol family is specified,
.Nm
will report only the details specific to that protocol family.
.Pp
If the
.Fl m
flag is passed before an interface name,
.Nm
will display the capability list and all
of the supported media for the specified interface.
If
.Fl L
flag is supplied, address lifetime is displayed for IPv6 addresses,
as time offset string.
.Pp
Optionally, the
.Fl a
flag may be used instead of an interface name.
This flag instructs
.Nm
to display information about all interfaces in the system.
The
.Fl d
flag limits this to interfaces that are down, and
.Fl u
limits this to interfaces that are up.
When no arguments are given,
.Fl a
is implied.
.Pp
The
.Fl l
flag may be used to list all available interfaces on the system, with
no other additional information.
Use of this flag is mutually exclusive
with all other flags and commands, except for
.Fl d
(only list interfaces that are down)
and
.Fl u
(only list interfaces that are up).
.Pp
The
.Fl v
flag may be used to get more verbose status for an interface.
.Pp
The
.Fl C
flag may be used to list all of the interface cloners available on
the system, with no additional information.
Use of this flag is mutually exclusive with all other flags and commands.
.Pp
The
.Fl k
flag causes keying information for the interface, if available, to be
printed.
For example, the values of 802.11 WEP keys will be printed, if accessible to
the current user.
This information is not printed by default, as it may be considered
sensitive.
.Pp 
If the network interface driver is not present in the kernel then
.Nm
will attempt to load it.
The
.Fl n
flag disables this behavior.
.Pp
Only the super-user may modify the configuration of a network interface.
.Sh NOTES
The media selection system is relatively new and only some drivers support
it (or have need for it).
.Sh EXAMPLES
Assign the IPv4 address
.Li 192.0.2.10 ,
with a network mask of
.Li 255.255.255.0 ,
to the interface
.Li fxp0 :
.Dl # ifconfig fxp0 inet 192.0.2.10 netmask 255.255.255.0
.Pp
Add the IPv4 address
.Li 192.0.2.45 ,
with the CIDR network prefix
.Li /28 ,
to the interface
.Li ed0 ,
using
.Cm add
as a synonym for the canonical form of the option
.Cm alias :
.Dl # ifconfig ed0 inet 192.0.2.45/28 add
.Pp
Remove the IPv4 address
.Li 192.0.2.45
from the interface
.Li ed0 :
.Dl # ifconfig ed0 inet 192.0.2.45 -alias
.Pp
Enable IPv6 functionality of the interface:
.Dl # ifconfig em0 inet6 -ifdisabled
.Pp
Add the IPv6 address
.Li 2001:DB8:DBDB::123/48
to the interface
.Li em0 :
.Dl # ifconfig em0 inet6 2001:db8:bdbd::123 prefixlen 48 alias
Note that lower case hexadecimal IPv6 addresses are acceptable.
.Pp
Remove the IPv6 address added in the above example,
using the
.Li /
character as shorthand for the network prefix,
and using
.Cm delete
as a synonym for the canonical form of the option
.Fl alias :
.Dl # ifconfig em0 inet6 2001:db8:bdbd::123/48 delete
.Pp
Configure the interface
.Li xl0 ,
to use 100baseTX, full duplex Ethernet media options:
.Dl # ifconfig xl0 media 100baseTX mediaopt full-duplex
.Pp
Label the em0 interface as an uplink:
.Dl # ifconfig em0 description \&"Uplink to Gigabit Switch 2\&"
.Pp
Create the software network interface
.Li gif1 :
.Dl # ifconfig gif1 create
.Pp
Destroy the software network interface
.Li gif1 :
.Dl # ifconfig gif1 destroy
.Pp
Display available wireless networks using
.Li wlan0 :
.Dl # ifconfig wlan0 list scan
.Sh DIAGNOSTICS
Messages indicating the specified interface does not exist, the
requested address is unknown, or the user is not privileged and
tried to alter an interface's configuration.
.Sh SEE ALSO
.Xr netstat 1 ,
.Xr carp 4 ,
.Xr gif 4 ,
.Xr netintro 4 ,
.Xr pfsync 4 ,
.Xr polling 4 ,
.Xr vlan 4 ,
.\" .Xr eon 5 ,
.Xr rc 8 ,
.Xr routed 8 ,
.Xr jail 8 ,
.Xr sysctl 8
.Sh HISTORY
The
.Nm
utility appeared in
.Bx 4.2 .
.Sh BUGS
Basic IPv6 node operation requires a link-local address on each
interface configured for IPv6.
Normally, such an address is automatically configured by the
kernel on each interface added to the system or enabled; this behavior may
be disabled by setting per-interface flag
.Cm -auto_linklocal .
The default value of this flag is 1 and can be disabled by using the sysctl
MIB variable
.Va net.inet6.ip6.auto_linklocal .
.Pp
Do not configure IPv6 addresses with no link-local address by using
.Nm .
It can result in unexpected behaviors of the kernel.