Networker for Unix (Solaris) V7.4

For the 2nd time in six months, I've had a very strange occurrence: My
"read-only" (RO) adv_file disk device decides to dismount itself in the
middle of the night, causing serious havoc (read: logjam next morning) on
the remaining backups, cloning, staging, etc.

The smoking gun can be seen on the system console:

[ID 702911 daemon.notice] NetWorker media: (waiting) waiting for adv_file
disk DiskStorage.RO on BackupServ1

Here is what is seen in the Networker device display when it is failed:

Name                   Volume Name
/bigdisk               DiskStorage
/bigdisk/_AF_readonly

Here is what is seen in the Networker device display after I manually
remount the RO disk device:

Name                   Volume Name
/bigdisk               DiskStorage
/bigdisk/_AF_readonly  DiskStorage.RO

Its status is properly set to ENABLED and READ ONLY in its properties.

------
Nobody is doing this manually, it is doing it all by itself. I've scanned
the EMC support database and have yet to find any mention of this kind of
behavior.

Before I report it to EMC support, I was wondering if anyone on this list
had any hints or suggestions as to what might be happening?

Thanks!

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