What's the straight scoop on booting?

[Joe Smith]

In article <1490 at brchh104.bnr.ca> haynes at ucscc.ucsc.edu (Jim Haynes) writes:
>The manuals say that the system when booting fires up /usr/etc/init. In
>my younger days a system came up with the root filesystem mounted but
>without /usr mounted.  I'm not sure I like the new arrangement; I'm
>working with some configurations where /usr is just a bunch of symlinks to
>other places.  What is the copy of init in /sbin for?  Do I have to have
>/usr mounted at boot time?  haynes at ucscc.ucsc.edu haynes at ucscc.bitnet

You can find some of the information you seek by doing the following:

1) ps ax | head
2) strings /sbin/init | more
3) grep mount /etc/rc.boot

When a diskless workstation boots up, only the root directory and the swap
space are defined.  The executables in /sbin are the minimum required to
mount /usr over NFS.  They are:

1) /sbin/init - started automatically by vmunix
2) /sbin/sh - used to interpret /etc/rc.boot
3) /sbin/hostname - defines primary host name
4) /sbin/ifconfig - sets up IP address for the ethernet interface
5) /sbin/intr (new with 4.1) - allows ^C to abort mount
6) /sbin/mount - mounts /usr, either over NFS or as a local partition

The above also applies to a diskfull Sun system.  The manuals you refer to
are wrong.

Joe Smith (408)922-6220 | SMTP: jms at tardis.tymnet.com or jms at gemini.tymnet.com
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