home *** CD-ROM | disk | FTP | other *** search
- Newsgroups: comp.sys.next.sysadmin
- Path: sparky!uunet!wri!news
- From: barker@saipan.wri.com (Harold Barker)
- Subject: kernel flags
- Message-ID: <1992Aug24.010750.10847@wri.com>
- Sender: news@wri.com
- Nntp-Posting-Host: saipan.wri.com
- Organization: Wolfram Research, Inc.
- Date: Mon, 24 Aug 1992 01:07:50 GMT
- Lines: 93
-
-
- Last week some questions were posted about what some kernel flags mean.
- her is a short list form a file called power_on.rtfd by Wayde Schroeder
- from SupportBulletin Volume 1, Issue 1 Summer 1991. I beleave this file
- to be on the archives someplace. The same info (rewriten) is in the 3.0
- Admin docs. The following text is taken directly from the above file. I
- have omited much of the file.
-
- boot flags
- Boot flags are used to specify boot options. The flags are preceded by a
- hyphen (-). When you specify boot flags, if no kernel name is given, the
- default mach kernel will be used. General usage when working from the ROM
- monitor includes adding the boot flags:
-
- bxx [kernel] -[flags]
-
- flags include:
-
- -a Ask for the name of the root device.
- -b Boot without running /etc/rc.boot.
- -s Boot in single-user mode.
- -i Ask for the name of the init program.
- -p Don't auto-reboot on a panic.
-
- Examples:
-
- bsd -s
- ben -bs
- bfd mymach -as
-
-
- and another
-
- kernel variables
- The complete list of kernel variables may be unique to each kernel built.
- This section discusses variables that will continue to be included in
- future releases and describes how they are used in various situations.
- General usage when working from the ROM monitor includes adding the kernel
- variables:
-
- bxx [kernel] -[flags] [kvars]
-
- where kvars includes the following kernel variables:
-
- mem=nnnn Use only nnnn KB of memory even though more is actually
- installed (for example, 1024 is 1 MB). Useful when measuring the impact of
- adding more (or less) memory.
-
- init=path Run path instead of /etc/mach_init.
-
- rootdev=xxx Use xxx (for example, sd1, od0, en0, fd0) as root device
- when boot device is different
-
- rootdir=path Use directory path as root point.
-
- rootrw=1 Mount the root read/write initially. At boot, the root is
- normally mounted read-only. If fsck runs clean during rc.boot, it's
- remounted read-write.
-
- cache=0 Disable the on-chip caches.
-
- pagesize=4096 Use physical pages half as large (default is 8192). This
- usually makes things worse.
-
- Examples:
-
- bod - rootdev=sd0 ( - needed when kernel name not given)
- bsd newmach -p mem=4096
-
-
- Here's an example of booting from an external floppy device when the
- internal disk is sd0, and the external floppy disk is sd1. Be sure to
- insert the MkMagic bootable floppy disk in the external floppy disk drive
- before you execute the following command:
-
- NeXT> bsd(1,0,0) - rootdev=sd1a
-
- references
- Network and System Administration manual, Chapter 11, System Startup and
- Shutdown. NeXT Computer, Inc., 1990.
-
- end of Wayde's text.
-
-
-
- --
- Work voice 217-398-0700 | Home
- barker@wri.com fax 217-398-0747 | barker@rhiannon.wri.com
- NeXT Mail accepted | NeXT Mail accepted
- --------------------------------------|-----------------------------------
- ---
- Mail sent to barker@wri.com will be copied to rhiannon, mail sent to
- barker@rhiannon.wri.com will not be seen at work ;-)
-