Problem with corrupt filesystem-any good log funktion?

[Fredrik Andersson]

Have problem that the filesystem be corrupt, but don't know why!
Look's that the server restart sometime and after it comes too the line
"Enter full patchname of shell or Return for /bin/sh"
After pushing return I do an fsck too repair the corrupt filesystem. After this all seems working ok again. 

Is there any good logging funktion that can get more facts about what can be the problem!??

The system is  4.9-RELEASE-p5 FreeBSD 4.9-RELEASE-p5 #0

Thanks....