Here's an interesting one.  We have a handful of AIX 4.3 boxes, we just noticed 
that they aren't backing up /usr or /usr/local anymore.
I go in and try to do an incremental, I get an ANR4014E error (internal system 
error).  I do an incr on a subdir of /usr (such as /usr/lpp)
it works fine, then I go back and to an incr specifically on /usr and it now 
works fine.  Then I do a straight incr and everything in
/usr gets expired again.  Then I go back to do another incr and we're back to 
the ANR40414E message again.

There's nothing in the include/exclude list excluding this stuff
I've checked to ensure it's using the correct dsm.sys, opt, and include list. 
(checked this one HARD)
I've checked to ensure the nodes aren't tied to a client options set.
When you do a q filespace on the server, it doesn't list the affected 
filesystems as even existing.

Another sympom that's indirectly related is that a few files fail on backup 
claiming that the mgmt class they're bound to has no backup
copygroup.  The default mgmt has a backup copygroup.

It all seems to point to an exclude list somewhere that I can't find.  Any 
ideas?

Later,
Paul