You probably want to get your systems up to date. I rather like the tool smpatch. You can just do «smpatch update» and it will apply most of the patches you need. Or you can do it step by step:
smpatch analyze: see what should be applied
smpatch download: download them
smpatch update: applies them
Again, I note that you don’t need analyze and download. Update will do that.
By default, update will only install patches that are fairly safe. I.e. they can be installed with the system running normally, and won’t cause trouble. Patches that require an immediate reboot will be skipped, and put into a file /var/sadm/spool/disallowed_patch_list. When you’re ready to do them, kick everybody off the system, shut down as much as you can, and do
smpatch add -x idlist=/var/sadm/spool/disallowed_patch_list