WARNING - /usr/sbin/fsck not found. Most likely the mount of
/usr failed or the /usr filesystem is badly
damaged. The system is being halted.
Either re-install the system of boot with -b
option in an attempt to recover
Anyone help me on restoring this without having to reinstall. it is a test machine I have so I can do anything on it at anytime (that's probably why I am in this situation in the first place! 
What changed? Any other errors about disk drives going bad? Was /usr it's own partition or changed recently?
Try booting into single user from cdrom (try to boot off the same version cdrom as the OS) and running fsck from it for the partition that was /usr. You might try mounting it first or mounting your / partition and looking at your /etc/vfstab.
I did umount the /usr file system foolishly as it seems now...
Silly question maybe..
How do I boot to single user mode from cdrom from where I am?
And I am sure I have the cd - is it just the solaris operating system cd I need?
Thanks for your help so far..
shutdown the system (or hit STOP-A on a sun keyboard)
insert cd into cdrom.
at the ok prompt type boot cdrom
then when the system comes up mount what ever FS you need mounted and do your fsck on it.
yes should be cd1 i believe.
Gave that a go -
boot cdrom with the OS cdrom in the drive...
It returns same error and goes straight to the okay and I cannot seem to mount the FS from here - any ideas how I can do this??
There is another error - It seems the solaris hits an error booting from cdrom... cannot open boot device
Any ideas how to get around this as I had no problem using the cdrom device previously
nope sorry.
you can try the other cd's but it should be the frst cd.
you shouldnt get that error if you are booting off of the cdrom.
unless your cd was coruppt.
if all else fails give sun a call. you should hopefully have a support contract.
i usually start my net searches w/ google groups. then i goto the solairs section. and type in my error and any keywords. its helped plenty of times.
wish i could be of more help sorry.
http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&group=comp.unix
What type of hardware (server) is this? What version of Solaris are you using (both cd and on the server now)?
Its an ultra 10 and I am running solaris 9
Any ideas?