Included below is the original question, plus the two responses that seemed
relevant enough to the question (ie. Solaris vs SunOS specific)
>>Hi...
>>
>> I'm currently patching up a few of the older Sun/Sparc's on our
>>network, and wonder if anyone can tell me what the procedure is if a kernel
>>patch causes a machine *not* to boot? How do I get at the old kernel so that
>>I can do a 'backoutpatch'?
>>
>> I know under SunOS 4.x.x, the kernel was /vmunix, and you just booted
>>/vmunix.old if the boot failed...but I can't find similar under Solaris.
>>
>>Thanks...
>>
>>Marc G. Fournier scrappy@hub.org
>>Systems Administrator @ hub.org scrappy@freebsd.org
>>
>>
=========
Boot single-user mode from cdrom
Mount the boot partition to the cdrom partition /a
copy /platform/sun4?/kernel/unix /a/platform/sun4?/kernel/unix
reboot.
To prevent this in the future, copy /platform/sun4?/kernel/unix
to /platform/sun4?/kernel/unix.backup
That way, during boot up you can specify that backup file.
Of course, substitute the ? above for c,m,or u, which ever
is appropriate.
Ellen
emarch@pinole1.com
=========
From: Cagri Yucel <cyucel@is.ku.edu.tr>
Well, did you do this ? or asking just for incase ? if so copy kernel and
genunix as .olds. If something goes wrong simply do a boot -ar, so prom
will ask you every kernel file to be loaded.
-cagri
=========
Marc G. Fournier
Systems Administrator @ hub.org
primary: scrappy@hub.org secondary: scrappy@{freebsd|postgresql}.org