> The event for the backup is 'FAILED', but when I looked at the schedule
> log, the report show 'Total number of objects failed:           0'

Objects failing do not cause the schedule to be marked as Failed.

> 01/07/1999 05:05:21 ANS1512E Scheduled event 'UNIX_DAILY' failed.
> Return code = 4.

This is the reason the schedule is marked as failed.  You should look thru
the entire schedule log for that day, and I think you will find an error
on one of the filesystems.  The disk could be going bad, or perhaps that
disk was detached, but the filesystems never umounted.  You should
probably run fsck against the filesystem that got the error.

Steve (unVMix Systems Programmer/Dude) Roder
(tkssteve AT ubvm.cc.buffalo DOT edu | tkssteve AT acsu.buffalo DOT edu | 
(716)645-3564 ,
   | http://ubvm.cc.buffalo.edu/~tkssteve)