I installed sun recommended cluster patches for solaris 2.5 on my
solaris 2.5 server and then issued a shutdown -i6 -y -g0 to reboot the server but server failed to come back up.
the server tries to boot up and goes through initialising memory then server freeze.
I try to bring the server up by
Pressing the stop -a keys on the keybord, which bring me to the ok prompt
then issued
boot cdrom -s to boot from cdrom
but what do I do from here I have never been in this situation before.
When you applied the recommended patches, were you in single user mode?
If not, then more than likely you have 'hosed' the system. One or more patch did not apply correctly because of the state of the server. It is causing a panic on the server.
If the server is actually up in single user - remove the patch.
OR
You could try booting cdrom -s and then mounting your different partitions under /mnt. You could then try to find the patch directory (where you installed from) and run the backoutpatch script (note you would have to change it to let it know that the real /, /usr, /whateverelse is actually under /mnt/, /mnt/usr, ...
If you don't it will fail for two reasons - one: you can't write to the / partition while booted from cdrom - and two, the cdrom doesn't have the patch on it)
If you can't do that - re-install the OS, apply patch in single user, init 0, boot -s (normally I would boot -s after applying a patch - just in case )
Another possible cause - a bad CPU or memory - but I don't find anything on SunSolve except software issues for that error.
BAD TRAP
Cause A bad trap can indicate faulty hardware or a mismatch between hardware and its configuration information. Data loss is possible if the problem occurs other than at boot time.
Action If you recently installed new hardware, verify that the software was correctly configured. Check the kernel traceback displayed on the console to see which device generated the trap. If the configuration files are correct, you will probably have to replace the device.
In some cases, the bad trap message indicates a bad or down-rev CPU.
Technical Notes A hardware processor trap occurred, and the kernel trap handler was unable to restore system state. This is a fatal error that usually precedes a panic, after which the system performs a sync, dump, and reboot. The following conditions can cause a bad trap: a system text or data access fault, a system data alignment error, or certain kinds of user software traps.
Your original message showed you were running Solaris 2.5. I don't believe patchrm was in the OS back then. I checked a 2.5.1 system and there is no such command.
If you are running 2.5, then you need to go to the directory where you originally installed the patch from - that sould be /tmp. (Problems sometimes occur with installing from other directories). You should have a 103xxx-xx directory. If you saved the files to allow a backout, then there should be a backout script to run (you don't want to use patchrm since that is not set up to remove all the patches added by the one you installed).
If this doesn't work - you have to reinstall the OS - no way around that.