Scanning NDMP tapes

[wamason]

This has me stumped. I need to recover data from NDMP tapes that were created in a retired datazone. I saved the media DB before I retired the datazone so I am able to query the DB. I found the 2 tapes I needed and scanned them into the new data zone. First tape scanned fine, asked for 2nd tape, scanned the second tape and is now asking for a 3rd tape, but there are no more tapes to be scanned for that saveset. I created the client with the same clientid as the old datazone. The queries from the old data zone turns up only 2 tapes.
I am only trying to scan in the media indexes so I am only using the -m and -S option with the scanner command.
Tapes have not been relabeled since the backup was done done in February.

Any suggestions would be greatly appreciated.

 

[Calippo]

Hi Wamason

You cant scan in an NDMP tape and rebuild you client index. The only thing you can use scanner for on an NDMP tape is to re-populate the media database with the saveset info and the volume info.

However, if you run the nsrck -L7 command you can recover the index, provided that the index saveset is backed up to an non-NDMP pool. If your NDMP backups were configured correctly you will have you index saveset going to differant media/pool because an index savaset is non-NDMP data and you cant recover this non-NDMP data from an NDMP tape... the NDMP tape is only readable on the NAS.

As you see, I have assumed your NAS backup is going to an NDMP pool. You could however be sending your NDMP datastream shooting across the LAN to a regular pool via a storage node, this type of NDMP backup is known as DSA and in this scenario your generic open tape format tape contains non-NDMP and NDMP data.

You could try a saveset recovery instead, that way you dont need the client index at all. provided the media database has the volume and saveset info. Do you know the nsrndmp_recover command syntax for that?


regards

---------------------------------------
EMCTA & EMCIE - Backup & Recovery
Legato & Commvault Certified Specialist
MCSE

 

[605]

EttaTeleco is correct. The reason is that for 'standard' NDMP backups, NetWorker does not control the data stream at all.

For new backups, you could use NetWorker's DSA feature which 'translates' the NDMP data to 'normal' NetWorker data. It has been introduced with NW 7.2 and does not need any license. Customers who use it love it.

 

[wamason]

Thanks. Correct me if I am wrong. I am only trying to rebuild the media index so that I can do a saveset recover. I will at least need to rebuild the media index in order to do the saveset recover. Please correcr me if my thoughts are wrong.
The problem that I am facing is that Networker is asking for a 3rd tape to rebuild the media index when in fact only 2 tapes were used to backup that saveset.
I am hoping that I can get solution (if possible) for this today.

 

[Calippo]

Hi Wamason

Can I suggest the following scanner command instead after the volume is loaded into Tape0:
scanner -m \\.\Tape0

You can move the volume with the following command if you wish:

nsrjb -nlvvv -j <jukeboxname> -S <slot#> -d \\.\Tape0

Remember to disable the idle device timeout first (on the library) because the volume may get ejected before the scanner completes in you dont.

Using the -m is really the only correct option as this rebuilds the media database entries. Dont use -i because you cant reconstruct the client index. Sometimes when you do scanner and specify a savesetID (-S) the command doesn't work properly. If is asks for more volumes than you have, dont worry.

You could then run the following mminfo command to verify the volumes you have scanned in:

mminfo -avot -x -q volume=<volume> -r client,name,savetime,ssid,cloneid,pssid,level,ssflags,clflags,sumflags,sumsize,totalsize,pool,volume,volflags,mediafile,type > volume.csv

Then verify the saveset info:
mminfo -xc, -avV -q ssid=<ssid> > saveset.csv

I hope this unravels the mystery!

---------------------------------------
EMCTA & EMCIE - Backup & Recovery
Legato & Commvault Certified Specialist
MCSE

 

[Calippo]

Ooopps... typo.
Command should be:
mminfo -avot -xc, -q volume=<volume> -r client,name,savetime,ssid,cloneid,pssid,level,ssflags,clflags,sumflags,sumsize,totalsize,pool,volume,volflags,mediafile,type > volume.csv

---------------------------------------
EMCTA & EMCIE - Backup & Recovery
Legato & Commvault Certified Specialist
MCSE

 

[wamason]

Thanks, it seems that I have scanned the media index successfully.
Now the recover is not woring. This is the comamnd that I am using:
nsrndmp_recover -c oldnasdevice -S 0123456789 -m newnasdevice::/vol/vol1/qtree/clientname/restore/ /vol/vol1/qtree/clientname

The only thing that changed is the nas filer. This command seems like it's browsing my backupserver (which is incorrect, I should be browsing oldnasdevice) and I keep getting
NSR server busy; retrying.

 

[Calippo]

Hi Wamason
The command syntax is:
nsrndmp_recover –s <NetWorkerSvr> –c <sourceHost> –S <SSID> –v off –m <desinationHost>::<desinationDirectory> <sourceDirectory>

Here's an example but since we are using the -S switch I am not 100% if the sourceHost switch needs to be specified:

nsrndmp_recover –D5 –s NetWorkerServer –c oldnasdevice –S 0123456789 –v off -m newnasdevice::/vol/vol1/qtree/clientname/restore/ /vol/vol1/qtree/clientname

This command isnt really too disimular to what you typed in but maybe give it a go just in case.

If you specify the "-v off" option in the command line then this will turn off the verify path (i.e. file and record offset information) within the client file index.
This means that it should switch off the DAR recover functionality during the recover allowing a file or directory level recovery. However, a saveset recover should not use DAR as you are recovering the whole saveset.

The -D5 switch is for debug output.

If this doesnt work you could try creating an empty file on the NetWorker server in the "...\nsr\debug" directory called "ndmp_auto_pos". If the recover issue is being caused by a missing file mark then this setting should allow the recover to complete successfully. Be sure to remove the ndmp_auto_pos file after the recover has completed.

If the recovery still failes you better log a support case with EMC.

---------------------------------------
EMCTA & EMCIE - Backup & Recovery
Legato & Commvault Certified Specialist
MCSE

 

[wamason]

I removed the media from the DM using nsrmm, then scanned the tapes without the ssid and everthing worked perfectly. Thanks for your help.