Networker

Re: [Networker] How to find a piece of a save set that spans?

2010-10-06 19:55:34
Subject: Re: [Networker] How to find a piece of a save set that spans?
From: George Sinclair <George.Sinclair AT NOAA DOT GOV>
To: NETWORKER AT LISTSERV.TEMPLE DOT EDU
Date: Wed, 6 Oct 2010 19:53:31 -0400
Werth, Dave wrote:
George,

I was playing around a bit with this in the NMC GUI and found if you go to "Media" and select 
"Save Sets" you can set a query for the save sets you are interested in.  Then in the "Save 
Set List" tab it gives you a list of all of the volumes that save set is on.

For instance a save set from my weekend full backup displays in the volume name 
column:

150021(1000.0,h),150022(1000.0,m),150023(1000.0,m),150024(1000.0,t)

That's the sort of information you're looking for, right?
Well, that tells me which volumes the save set is split across and the
size of each such piece (on each volume). That's the same as running an
'mminfo' command and reporting the various fields, e.g.
sumflags,sumsize,totalsize,volume ...
What I actually need is a way to find a file or directory or something
that's contained within the save set itself but is split across tapes 1
and 2. Clearly, once the first tape (h) is full, it then moves onto the
next tape (m), but what file, from that save set, is actually split
between those two tapes? I'd like to be able to determine that also for
volumes 2 and 3 and 3 and 4. In my case, I don't really need to go down
to the actual file name itself, just the top level parent directory
that's directly beneath the save set.
For example, let's say the save set name is '/export/dir1/data', and the
save set spans four tapes. Let's assume that 'data' contains hundreds of
sub-directories named: 0001, 0002, 0003, 0004 ... Which one of those
directories spans both tapes 1 and 2? Which one spans both tapes 2 and
3, tapes 3 and 4? That's what I need to find out. In my case, none of
these directories is large enough to span more that two tapes.
BTW: What does the '1000.0' value refer to? I see that on my end, too.
In fact, it looks to always be that same value. The volume names and the
'h', 'm' and 't' values make perfect sense and concur with what
'volume,sumflags' shows from 'mminfo', but the '1000.0' has me confused.
George

Dave Werth
Garmin AT, Inc.
Salem, Oregon

-----Original Message-----
From: EMC NetWorker discussion [mailto:NETWORKER AT LISTSERV.TEMPLE DOT EDU] On 
Behalf Of George Sinclair
Sent: Wednesday, October 06, 2010 4:01 PM
To: NETWORKER AT LISTSERV.TEMPLE DOT EDU
Subject: Re: [Networker] How to find a piece of a save set that spans?

Werth, Dave wrote:
Yes, I like slick too but sometimes when it's something you're only doing once 
or twice for testing purposes and don't need it on an ongoing basis then brute 
force methods are adequate.
I agree, but in this case, there's so many top level directories for
some of these save sets that it could take me an unacceptably long time.
Would the following scenario possibly work???:

Obviously, I can run 'mminfo' and have it tell me the size (sumsize) of each piece of the save set that's on each volume. Let's say there's four pieces, and I specify something like 'sumsize(20)' to have it list it out in actual bytes. So what if I then run 'nsrinfo -s server -t nsavetime -v client' for the given save set and capture that to an output file. That will list all the pieces/parts in the save set, file by file, with the 'NSR size' and 'file size' of each. Next, I write a script to parse that output file and add up the sizes until it hits something close to the 'sumsize(20)' for the first volume. Once it hits that, it then prints out the pathname of that file. I then manually check to see if that directory spans. If not, it's probably one of the directories just before or after that? I could then do this for the second piece and third piece. In this example, the fourth piece would be the last so that would be moot.
Assuming this harebrained scheme would even work, I'm not sure what the
difference between 'NSR size' and 'file size' is, but 'NSR size' is
always a little bigger. Maybe I would want to use 'NSR size' for this?
Also, is the order that 'nsrinfo' lists everything in the same as the
order that the data was actually backed up? If not, this goofy method
won't work.
Maybe there's a better way (sigh ...).

George

Dave Werth
Garmin AT, Inc.
Salem, Oregon

-----Original Message-----
From: EMC NetWorker discussion [mailto:NETWORKER AT LISTSERV.TEMPLE DOT EDU] On 
Behalf Of George Sinclair
Sent: Wednesday, October 06, 2010 3:31 PM
To: NETWORKER AT LISTSERV.TEMPLE DOT EDU
Subject: Re: [Networker] How to find a piece of a save set that spans?

Werth, Dave wrote:
George,

I don't know about how you can determine ahead of time what directories will span 
multiple volumes but you can certainly go into Recover and select a directory to recover 
then check the "Show required volumes" display to see if in fact it does span 
volumes.  I don't imagine it would take too long to find one that did (but then what do I 
know?).
Yes, that's exactly what I'm looking for: a way to determine which directories did in fact span tapes, NOT which ones will span tapes. So, this is an "after the fact" question. I can certainly do as you mentioned but was looking for a slick way to determine this without trial and error?
Some of the save sets have a small number of top level sub-directories
so it won't take too long to find one that spans, but most of the save
sets have a lot of top level sub-directories, so that will take much
longer. Obviously, at least one of them must span two tapes.
George

Dave Werth
Garmin AT, Inc.
Salem, Oregon
-----Original Message-----
From: EMC NetWorker discussion [mailto:NETWORKER AT LISTSERV.TEMPLE DOT EDU] On 
Behalf Of George Sinclair
Sent: Wednesday, October 06, 2010 3:08 PM
To: NETWORKER AT LISTSERV.TEMPLE DOT EDU
Subject: [Networker] How to find a piece of a save set that spans?

Hi,

We have 19 save sets that we've just backed up. These have also been
cloned. Each of these save sets is 1+ TB and consist of a number of
smaller sized sub-directories, e.g. 300 KB, 2.4 GB, 19 GB, etc. The tape
pool is indexed. All of these save sets span multiple tapes (minimally
3-4 tapes) as they were multiplexed together (parallelism=4) during backup.

I'd like to run a browseable recover test (nwrecover or CLI recover) on
   a couple of random sub-directories from each save set, but I'd like
to also pick a few that span at least two tapes. I don't want to recover
the whole save set, however, as these are all very large.

Is there a way I can determine which directories span two tapes?

Will I have to just select random directories, using nwrecover or CLI
recover, until I find one that shows two volumes required?

Thanks.

George

--
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


This e-mail and any attachments may contain confidential material for the sole 
use of the intended recipient. If you are not the intended recipient, please be 
aware that any disclosure, copying, distribution or use of this e-mail or any 
attachment is prohibited. If you have received this e-mail in error, please 
contact the sender and delete all copies.

Thank you for your cooperation.




--
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