Get the cause of a crash wtihout /var?

I was updating a v490 from Sol10_u5 to Sol10_u10. The upgrade went fine, but
on reboot afterwards the /var partition was totally corrupted and could not be
mounted. I tried to fsck, but after thousands of unlinked inodes and the like
we newfs-ed the partition and restored from tape. The system is now fine and
updated. But management would (understandably) like a postmortem and
root-cause-analysis report. Can anyone think of a way to get a record of what
happened on a system without using any information from /var?


Christopher L. Barnard
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comment your code as if the maintainer is a homicidal maniac who knows where
you live.