Networker

Re: [Networker] Stage from tape to tape

2010-10-15 15:34:45
Subject: Re: [Networker] Stage from tape to tape
From: George Sinclair <George.Sinclair AT NOAA DOT GOV>
To: NETWORKER AT LISTSERV.TEMPLE DOT EDU
Date: Fri, 15 Oct 2010 15:32:40 -0400
Francis Swasey wrote:
George,

Think of nsrstage as an nsrclone/nsrmm -d pair.  That's really all that is 
happening under the
covers.  If you watch with NMC, when an ssid is being staged (moved) from one 
device to
another, it shows up in the listing as a "clone job".  Once the clone is 
finished, then
NetWorker deletes the pointers to the data on the original media.

The stated purpose of this exercise was to reclaim the tapes that had some bit 
of valid data
left on them, therefore, nsrstage seems to be the best use to copy the data to 
another tape and
then mark the copy on the original tape as no longer needed.

Since it can't actually delete the data from the source tape(s) like it could with a file type device, what happens to that affected data? How is it marked as no longer needed?

We can't actually get that physical space back, so I assume it remains there on the original tape(s), and NW removes it from the media database as it would if you'd used 'nsrmm -d -S ssid/cloneid' but the new copy is still in the media database with the same ssid but a different cloneid?

Do I have that right?

George


Frank

On 10/15/10 12:03 PM, George Sinclair wrote:
Francis Swasey wrote:
On unix (or linux):

mminfo -q 'volume=<tape_volume>,!suspect,!incomplete,!ssrecycle,!recoverable' 
-r ssid,cloneid
-xc/ | grep -v ssid | xargs -n1 -t nsrstage -m -v -b '<media pool to write to>' 
-S

Fransis, that's interesting. I've never done this, but it makes sense. I've 
always just cloned
them to another tape, but that does require having, or creating, a 'clone' 
pool, which might be
a nuisance or disadvantage. I guess I never thought of the nsrstage command in 
this way. I've
always used it for clearing out save sets on a file type device wherein the 
save sets are first
cloned to tape and then deleted from the file type device.

So, it seems that this is a way to copy data from one tape to another without 
having to clone
or use scanner with uasm and all that business?

End the end, what is the advantage of doing this versus just, say, cloning 
(nsrclone)? I'm
trying to better understand for my future benefit.

Thanks.

George

I suggest you use "man mminfo" and "man nsrstage" to understand the various 
arguments.

Frank

On 10/15/10 4:39 AM, kleese2 wrote:
Can anyone tell me what the nsrstage cammand should look like.
I'm planning on staging these savesets one by one and not use a file to define 
them.




--
George Sinclair
Voice: (301) 713-3284 x210
- The preceding message is personal and does not reflect any official or unofficial position of the United States Department of Commerce -
- Any opinions expressed in this message are NOT those of the US Govt. -

To sign off this list, send email to listserv AT listserv.temple DOT edu and type 
"signoff networker" in the body of the email. Please write to networker-request 
AT listserv.temple DOT edu if you have any problems with this list. You can access the 
archives at http://listserv.temple.edu/archives/networker.html or
via RSS at http://listserv.temple.edu/cgi-bin/wa?RSS&L=NETWORKER