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diff --git a/usr.sbin/config/SMM.doc/b.t b/usr.sbin/config/SMM.doc/b.t deleted file mode 100644 index 901a009..0000000 --- a/usr.sbin/config/SMM.doc/b.t +++ /dev/null @@ -1,137 +0,0 @@ -.\" 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. -.\" -.\" @(#)b.t 8.1 (Berkeley) 6/8/93 -.\" -.\".ds RH "Device Defaulting Rules -.bp -.LG -.B -.ce -APPENDIX B. RULES FOR DEFAULTING SYSTEM DEVICES -.sp -.R -.NL -.PP -When \fIconfig\fP processes a ``config'' rule which does -not fully specify the location of the root file system, -paging area(s), device for system dumps, and device for -argument list processing it applies a set of rules to -define those values left unspecified. The following list -of rules are used in defaulting system devices. -.IP 1) 3 -If a root device is not specified, the swap -specification must indicate a ``generic'' system is to be built. -.IP 2) 3 -If the root device does not specify a unit number, it -defaults to unit 0. -.IP 3) 3 -If the root device does not include a partition specification, -it defaults to the ``a'' partition. -.IP 4) 3 -If no swap area is specified, it defaults to the ``b'' -partition of the root device. -.IP 5) 3 -If no device is specified for processing argument lists, the -first swap partition is selected. -.IP 6) 3 -If no device is chosen for system dumps, the first swap -partition is selected (see below to find out where dumps are -placed within the partition). -.PP -The following table summarizes the default partitions selected -when a device specification is incomplete, e.g. ``hp0''. -.DS -.TS -l l. -Type Partition -_ -root ``a'' -swap ``b'' -args ``b'' -dumps ``b'' -.TE -.DE -.SH -Multiple swap/paging areas -.PP -When multiple swap partitions are specified, the system treats the -first specified as a ``primary'' swap area which is always used. -The remaining partitions are then interleaved into the paging -system at the time a -.IR swapon (2) -system call is made. This is normally done at boot time with -a call to -.IR swapon (8) -from the /etc/rc file. -.SH -System dumps -.PP -System dumps are automatically taken after a system crash, -provided the device driver for the ``dumps'' device supports -this. The dump contains the contents of memory, but not -the swap areas. Normally the dump device is a disk in -which case the information is copied to a location at the -back of the partition. The dump is placed in the back of the -partition because the primary swap and dump device are commonly -the same device and this allows the system to be rebooted without -immediately overwriting the saved information. When a dump has -occurred, the system variable \fIdumpsize\fP -is set to a non-zero value indicating the size (in bytes) of -the dump. The \fIsavecore\fP\|(8) -program then copies the information from the dump partition to -a file in a ``crash'' directory and also makes a copy of the -system which was running at the time of the crash (usually -``/kernel''). The offset to the system dump is defined in the -system variable \fIdumplo\fP (a sector offset from -the front of the dump partition). The -.I savecore -program operates by reading the contents of \fIdumplo\fP, \fIdumpdev\fP, -and \fIdumpmagic\fP from /dev/kmem, then comparing the value -of \fIdumpmagic\fP read from /dev/kmem to that located in -corresponding location in the dump area of the dump partition. -If a match is found, -.I savecore -assumes a crash occurred and reads \fIdumpsize\fP from the dump area -of the dump partition. This value is then used in copying the -system dump. Refer to -\fIsavecore\fP\|(8) -for more information about its operation. -.PP -The value \fIdumplo\fP is calculated to be -.DS -\fIdumpdev-size\fP \- \fImemsize\fP -.DE -where \fIdumpdev-size\fP is the size of the disk partition -where system dumps are to be placed, and -\fImemsize\fP is the size of physical memory. -If the disk partition is not large enough to hold a full -dump, \fIdumplo\fP is set to 0 (the start of the partition). |