Networker

Re: [Networker] Change in Volume Labels

2008-02-29 13:55:19
Subject: Re: [Networker] Change in Volume Labels
From: Andrew Dietz <andrew.dietz AT OIT.GATECH DOT EDU>
To: NETWORKER AT LISTSERV.TEMPLE DOT EDU
Date: Fri, 29 Feb 2008 13:52:26 -0500
Thanks for all responses. The problem was indeed an incorrect ordering of tape drives in the library. I'm in the middle of fixing that right now...

Again thanks!!
Andrew Dietz


Stuart Whitby wrote:
My experience of duplicate tape labels has generally been that they occur when a tape is read from the wrong drive (jukebox drive ordering issues). NetWorker loads volume A to append new savesets, reads the header of volume B, then, if volume B is expired, labels a 2nd instance of volume A and deletes the previous entries from the media database (barcodes are arbitrary in NetWorker - all media is identified by its volume label, and you can't have 2 seperate SSIDs at Volume A, filemark 1). This is a nightmare situation to recover from as you now have 2 (or more) volumes with different barcodes but the same volume label. Only one of these has an associated barcode entry in the media database, and the data on the other volumes is no longer accessable. This isn't a case of swapping barcode labels, it's a case of identifying all duplicates via an nsrjb -Ip to load and check each volume label against its barcode - it's best to have the drive ordering problem sorted out before doing this ;) Then you have to take all of the tapes out where volid != barcode and put them in storage somewhere until everything's expired, or ideally scan each of them, clone off the data, then scan in the final one again to ensure that no data is lost. The ~....-1 barcode may be an attempt by Legato engineering to get around this issue without the usual "data loss" (from the media db) in the event of this issue. I hope so anyway :) Cheers, Stuart.

________________________________

From: EMC NetWorker discussion on behalf of Peter Viertel
Sent: Fri 29/02/2008 05:58
To: NETWORKER AT LISTSERV.TEMPLE DOT EDU
Subject: Re: [Networker] Change in Volume Labels



Usually duplicate label problems come up when it's trying to relabel a
tape and the process goes wrong - eg it updates the media database, then
finds the tape is unwriteable, or the media db update fails but the tape
label is overwritten - over the years I have noticed a few changes
(especially around the 7.2.2 versions) to try and get some sort of
transactional control over this process - but the problems still persist
it seems.

Here's three ways to possibly mess up tape labels.

1. jukebox definition is incorrect and tape drives are not in the right
order, leads to the wrong tape being labelled, and then a constant
series of complaints that the barcode doesn't match the label. Once the
hardware definition is fixed you're faced with having to swap the sticky
barcode labels around.

2. corrupt media db - updates to records fail silently, later on when
it's verifying a tape it barfs at the apparent mismatch... In the worst
cases after you've sorted out the media db (with help from EMC tech
support)   you have to delete the volume and use scanner -m to put it
back in the media db...

3. WP tab on cartridge is set.   This shouldn't cause problems with
recent versions of networker though. When relabelling tapes, networker
first renames the mediadb record to have a tilda - eg like what you see
QA0783 becomes  ~QA0783-1, then it goes to wipe the tape. If it's Write
protected or some drive problem prevents writing this will fail, and the
medaidb record is reverted to its original details. At least that's how
its supposed to work, it's based on an assumption that the mediadb will
always work, I've previosuly had a lot of problems with the mediadb
locking up during a bootstrap operation.


Of course I don't really know what they've done in 7.4.1 yet,    perhaps
it's changed again and you're looking at a new bug.
-----Original Message-----
From: EMC NetWorker discussion
[mailto:NETWORKER AT LISTSERV.TEMPLE DOT EDU] On Behalf Of Andrew Dietz
Sent: Friday, 29 February 2008 3:07 AM
To: NETWORKER AT LISTSERV.TEMPLE DOT EDU
Subject: Re: [Networker] Change in Volume Labels

More info:

This is what I found in the daemon.raw logs:

40027 02/20/08 18:08:00  2 0 0 1 631 0 scotch.tape.gatech.edu
nsrmmdbd
Rename volume with duplicate name, volid:223463453
34a444a2-00000005-0d51c81d-4651c81d-34fd0000-82cfa5f4 name:QA0783
flags:0x00000811 kb:435057536 files:151 tm:07/06/07 22:42:22 05/21/07
12:26:05 undef
32295 02/20/08 18:09:01  2 0 0 1 631 0 scotch.tape.gatech.edu
nsrmmdbd
XCHK volid:223463453 name:~QA0783-1 (395 to 0) savesets
flags:0x00000811
kb:435057536 ctime:05/21/07 atime:07/06/07

I can't imagine why NetWorker would think it found a
duplicate volume as
all our tapes are sequentially numbered....




Andrew Dietz wrote:
Under what circumstances does NetWorker change a wolume
label? We use
volume labels that match the barcode id, and some started
showing up
with a modified label. For example we had a volume with
label "QA0783"
that has recently been marked as "recyclable" by NetWorker
(it is not
set to expire until 3/5!) and it's volume is now
"~QA0783-1". I'm not
sure what's causing this to happen.

Any help is greatly appreciated.

Andrew Dietz

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
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


NOTICE
This e-mail and any attachments are confidential and may contain copyright 
material of Macquarie Group Limited or third parties. If you are not the 
intended recipient of this email you should not read, print, re-transmit, store 
or act in reliance on this e-mail or any attachments, and should destroy all 
copies of them. Macquarie Group Limited does not guarantee the integrity of any 
emails or any attached files. The views or opinions expressed are the author's 
own and may not reflect the views or opinions of Macquarie Group Limited.

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



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

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