Hi Louis
I'm running a very similar setup to you...
Networker 7.4.2 on Solaris 10
DataDomain  690 restorer connected directly to the backup server via 3 x 1Gb 
connections with another 1Gb connection to the WAN for replication off-site.
DD adv_file device is NFS mounted.
We've been running this for almost a year now and I haven't seen any problems 
with the adv_file device unmounting itself.

The mount command we use takes the form...
mount –F nfs –o intr,hard,rsize=32768,wsize=32768,proto=tcp,vers=3 
<ddrhostname>:/backup <mount-point>
and we've done all the recommended tcp/nfs tweaks (let me know if you need a 
list of those).

The one difference I can see from your post is that we don't have Auto Media 
Management enabled on the adv_file device.  I can't find anything to back this 
statement up, but I'm sure I saw something in the dim and distant past about 
not enabling that. You could try turning that off and see if it helped?  Is 
there a particular reason you have that turned on?

Hope this helps...
Allan.

________________________________________
From: EMC NetWorker discussion [NETWORKER AT LISTSERV.TEMPLE DOT EDU] On Behalf 
Of Louis Munro [lm AT LOUISMUNRO DOT COM]
Sent: 11 March 2010 18:32
To: NETWORKER AT LISTSERV.TEMPLE DOT EDU
Subject: [Networker] Waiting for an already mounted volume

Hello list users,

I'm having some problems with Networker backing-up to adv_file devices on my
brand new DataDomain Storage device.

Every so often (on average once a week) Networker will stop while doing the
backups and complain about the following (from the daemon log):

nsrd media request critical: Waiting for 1 writable volumes to backup pool
'DataDomain UNIX FS' tape or disk

The thing is, the volume is there. It is already mounted and available. We
have to manually unmount it and then Networker will remount it (since auto
media management is enabled) and resume the backups.

Is anyone else having that problem?

We are running NetWorker 7.4.5.Build.746 Network Edition on Solaris 10. The
adv_file is an NFS share exported from a DataDomain NAS. The share is
automounted on demand (using autofs) and a network problem is not suspected
at this time (we are able to cd to the adv_file directory when the problem
occurs).

The storage node is connected directly to the NAS through ethernet (i.e. a
crossover link).



Any ideas?

(Apologies for a possible douple posting. It looks like exchange ate my
first email to the list.)

Louis Munro

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