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diff --git a/share/doc/smm/02.config/2.t b/share/doc/smm/02.config/2.t new file mode 100644 index 000000000000..34e6b6349b22 --- /dev/null +++ b/share/doc/smm/02.config/2.t @@ -0,0 +1,188 @@ +.\" Copyright (c) 1983, 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. +.\" 3. All advertising materials mentioning features or use of this software +.\" must display the following acknowledgement: +.\" This product includes software developed by the University of +.\" California, Berkeley and its contributors. +.\" 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. +.\" +.\" @(#)2.t 8.1 (Berkeley) 6/8/93 +.\" +.\".ds RH "Configuration File Contents +.ne 2i +.NH +CONFIGURATION FILE CONTENTS +.PP +A system configuration must include at least the following +pieces of information: +.IP \(bu 3 +machine type +.IP \(bu 3 +cpu type +.IP \(bu 3 +system identification +.IP \(bu 3 +timezone +.IP \(bu 3 +maximum number of users +.IP \(bu 3 +location of the root file system +.IP \(bu 3 +available hardware +.PP +.I Config +allows multiple system images to be generated from a single +configuration description. Each system image is configured +for identical hardware, but may have different locations for the root +file system and, possibly, other system devices. +.NH 2 +Machine type +.PP +The +.I "machine type" +indicates if the system is going to operate on a DEC VAX-11\(dg computer, +.FS +\(dg DEC, VAX, UNIBUS, MASSBUS and MicroVAX are trademarks of Digital +Equipment Corporation. +.FE +or some other machine on which 4.4BSD operates. The machine type +is used to locate certain data files which are machine specific, and +also to select rules used in constructing the resultant +configuration files. +.NH 2 +Cpu type +.PP +The +.I "cpu type" +indicates which, of possibly many, cpu's the system is to operate on. +For example, if the system is being configured for a VAX-11, it could +be running on a VAX 8600, VAX-11/780, VAX-11/750, VAX-11/730 or MicroVAX II. +(Other VAX cpu types, including the 8650, 785 and 725, are configured using +the cpu designation for compatible machines introduced earlier.) +Specifying +more than one cpu type implies that the system should be configured to run +on any of the cpu's specified. For some types of machines this is not +possible and +.I config +will print a diagnostic indicating such. +.NH 2 +System identification +.PP +The +.I "system identification" +is a moniker attached to the system, and often the machine on which the +system is to run. For example, at Berkeley we have machines named Ernie +(Co-VAX), Kim (No-VAX), and so on. The system identifier selected is used to +create a global C ``#define'' which may be used to isolate system dependent +pieces of code in the kernel. For example, Ernie's Varian driver used +to be special cased because its interrupt vectors were wired together. The +code in the driver which understood how to handle this non-standard hardware +configuration was conditionally compiled in only if the system +was for Ernie. +.PP +The system identifier ``GENERIC'' is given to a system which +will run on any cpu of a particular machine type; it should not +otherwise be used for a system identifier. +.NH 2 +Timezone +.PP +The timezone in which the system is to run is used to define the +information returned by the \fIgettimeofday\fP\|(2) +system call. This value is specified as the number of hours east +or west of GMT. Negative numbers indicate a value east of GMT. +The timezone specification may also indicate the +type of daylight savings time rules to be applied. +.NH 2 +Maximum number of users +.PP +The system allocates many system data structures at boot time +based on the maximum number of users the system will support. +This number is normally between 8 and 40, depending +on the hardware and expected job mix. The rules +used to calculate system data structures are discussed in +Appendix D. +.NH 2 +Root file system location +.PP +When the system boots it must know the location of +the root of the file system +tree. This location and the part(s) of the disk(s) to be used +for paging and swapping must be specified in order to create +a complete configuration description. +.I Config +uses many rules to calculate default locations for these items; +these are described in Appendix B. +.PP +When a generic system is configured, the root file system is left +undefined until the system is booted. In this case, the root file +system need not be specified, only that the system is a generic system. +.NH 2 +Hardware devices +.PP +When the system boots it goes through an +.I autoconfiguration +phase. During this period, the system searches for all +those hardware devices +which the system builder has indicated might be present. This probing +sequence requires certain pieces of information such as register +addresses, bus interconnects, etc. A system's hardware may be configured +in a very flexible manner or be specified without any flexibility +whatsoever. Most people do not configure hardware devices into the +system unless they are currently present on the machine, expect +them to be present in the near future, or are simply guarding +against a hardware +failure somewhere else at the site (it is often wise to configure in +extra disks in case an emergency requires moving one off a machine which +has hardware problems). +.PP +The specification of hardware devices usually occupies the majority of +the configuration file. As such, a large portion of this document will +be spent understanding it. Section 6.3 contains a description of +the autoconfiguration process, as it applies to those planning to +write, or modify existing, device drivers. +.NH 2 +Pseudo devices +.PP +Several system facilities are configured in a manner like that used +for hardware devices although they are not associated with specific hardware. +These system options are configured as +.IR pseudo-devices . +Some pseudo devices allow an optional parameter that sets the limit +on the number of instances of the device that are active simultaneously. +.NH 2 +System options +.PP +Other than the mandatory pieces of information described above, it +is also possible to include various optional system facilities +or to modify system behavior and/or limits. +For example, 4.4BSD can be configured to support binary compatibility for +programs built under 4.3BSD. Also, optional support is provided +for disk quotas and tracing the performance of the virtual memory +subsystem. Any optional facilities to be configured into +the system are specified in the configuration file. The resultant +files generated by +.I config +will automatically include the necessary pieces of the system. |