Restart Verify job

[pmcdonald]

I've had a few tape anomalies lately and need to run a verify job to check the media. The problem is the backup set consists of about 40 tapes, each taking half a day to verify. I need to run nightly backups so can't afford the downtime of the month or two the verify job would take to complete. Is there any way to pause or stop a verify job and pick it up where it left off at a later date? I'm guessing no but thought I'd ask anyway...

 

Thanks

[Lennart_T]

You could set all tapes as "Missing", except the one you want to check. Then set all tapes back to "found" before running the backup at night.

 

I would never allow a tape backup set to grow to 40 tapes. What id you need to do a full restore? Then you may need to insert all 40 tapes, just to find a few files on each tape.

[jotrago]

At the simplest level if you deprive the verify job of the tapes it needs it will just stop in "Awaiting Media" mode.

So you could set it going, then during your backup window ensure that only your backup tapes are available, when the backup finishes replace the verify tapes.

If your library has cartridges which hold batches of tapes the above process may be mecahnically fairly simple.

 

 

With a 40 Tape backupset I guess you have a tape library or autochanger of some sort, and possibly the "Advanced Tape Support" license to use multiple drives.

Can you give us details of your setup, What version of Retrospect, MultiServer/Server/Pro and which release and platform.  What backup devices you have, eg how many drives / slots etc.

If you have multiple drives you may be able to bind a drive to the verify job, and use the other(s) for backups.

There is a "Binding" Tab on the Storage Devices Window that allows youmanually allocate Drives to Backup sets.

See the Manual Ch7 Controlling Operations > Multiple Concurrent Executions > Mutiple Drives > Binding tape Backup Sets to Tape Drives

 

Verify Jobs have an option to only verify "Unverified" backupsets, so you can run the same job and it will find anything that needs verifying, ignoring anything already verified.

See Manual Ch11 Tools > Maintenance & Repair > Verifying Backup Media

[jotrago]

Also on the Verify Job Configuration as I mentioned you set the option for "Verify backups not previously verified"

And you can build a schedule so that the verify only runs outside your backup times.

EG; Every day from 0600 to 1900 for verify and 1900 to 0600 for Backup

[pmcdonald]

You could set all tapes as "Missing", except the one you want to check. Then set all tapes back to "found" before running the backup at night.

 

I would never allow a tape backup set to grow to 40 tapes. What id you need to do a full restore? Then you may need to insert all 40 tapes, just to find a few files on each tape.

 

Thanks, good trick. I'll give that a go.

 

The reason for the crazy huge tape count is the backup set stores finished archived jobs. So typically we would only ever ingest one or two jobs spanning a tape or two at a time. At the time it made more sense in my head to put all the archived jobs in one set to maximise tape capacity and ensure we could search the entire archive of work if we were searching for elements that we weren't sure belonged to a specific job. Does that make sense?

 

 

With a 40 Tape backupset I guess you have a tape library or autochanger of some sort, and possibly the "Advanced Tape Support" license to use multiple drives.

Can you give us details of your setup, What version of Retrospect, MultiServer/Server/Pro and which release and platform.  What backup devices you have, eg how many drives / slots etc.

If you have multiple drives you may be able to bind a drive to the verify job, and use the other(s) for backups.

There is a "Binding" Tab on the Storage Devices Window that allows youmanually allocate Drives to Backup sets.

See the Manual Ch7 Controlling Operations > Multiple Concurrent Executions > Mutiple Drives > Binding tape Backup Sets to Tape Drives

 

Verify Jobs have an option to only verify "Unverified" backupsets, so you can run the same job and it will find anything that needs verifying, ignoring anything already verified.

See Manual Ch11 Tools > Maintenance & Repair > Verifying Backup Media

 

Afraid not re: the autochanger. See my response above.

 

Running Retrospect 7 on a Windows 7 PC and backing up to a single slot Dell LTO5 deck.

 

I'll try altering the options after I finish my backup, cheers.

 

Thanks for the responses, I appreciate them!

[jotrago]

So with a standalone drive, you simply dont insert the next tape for your verify job. It will sit patiently "Awaiting Media" while you feed tapes for your Backup job. When that is finished insert the next tape for the verify job and it should continue. Assuming it takes around 4-6 hours to verify an LTO5 tape you would need to time things so that you give the verify job time to finish a tape before the backup is due to start.

So you could end up with sequence something like this

08:00 start Verify insert first Tape 13:00;  insert 2nd verify Tape;  17:00 Start Backup & insert Backup Tape;  07:00 Backup finished;  remove backup tape, repeat

THe process would then take about a month for you 40 tapes.

 

 

At the time it made more sense in my head to put all the archived jobs in one set to maximise tape capacity and ensure we could search the entire archive of work if we were searching for elements that we weren't sure belonged to a specific job. Does that make sense?

That would seem to be a logical approach. However with Retrospect the bigger the saveset, the bigger the Catalog the longer it takes to search.

Have you actually tried a search? Was the search time acceptable?

 

Perhaps going forward create many archive backupsets based on a logical attribute of your archive jobs (Date, Customer, Subject etc).

It would also be possible, (although a lengthy process) to re-organise your existing Archive set by using the Transfer BackupSet function to move backup sets to new tapes according to your new scheme.

[pmcdonald]

So with a standalone drive, you simply dont insert the next tape for your verify job. It will sit patiently "Awaiting Media" while you feed tapes for your Backup job. When that is finished insert the next tape for the verify job and it should continue. Assuming it takes around 4-6 hours to verify an LTO5 tape you would need to time things so that you give the verify job time to finish a tape before the backup is due to start.

So you could end up with sequence something like this

08:00 start Verify insert first Tape 13:00;  insert 2nd verify Tape;  17:00 Start Backup & insert Backup Tape;  07:00 Backup finished;  remove backup tape, repeat

THe process would then take about a month for you 40 tapes.

 

 

All good BUT our daily backup task goes to backup set A and our archival library is stored on backup set B, which is the one I'm trying to verify. (The reasoning being if a catalog or tape set becomes irreparably corrupted we essentially have a duplicate to fall back on.) I think the sequence mentioned above only works if the daily task and the verify job are referencing the same project? I tried the method where I inserted the daily backup tape when the verify job was requesting the next tape and nothing, the scheduled daily task didn't begin.

 

 

That would seem to be a logical approach. However with Retrospect the bigger the saveset, the bigger the Catalog the longer it takes to search.

Have you actually tried a search? Was the search time acceptable?

 

Perhaps going forward create many archive backupsets based on a logical attribute of your archive jobs (Date, Customer, Subject etc).

It would also be possible, (although a lengthy process) to re-organise your existing Archive set by using the Transfer BackupSet function to move backup sets to new tapes according to your new scheme.

 

Search time is perfectly acceptable - it takes about 20 seconds to search and display an index of the entire 40 tape backup set. Daily backup is quite slow at about 40 minutes to read our 40TB NAS, but I suspect that's due to the shear amount of files it has to crawl as opposed to the time taken to cross reference the existing backup contents.

 

I see the logic in smaller backup sets but often staff without knowledge of a job will need to cast a wider net to find random elements (quotes, stock shots, sound effects, that sort of thing), hence the reluctant necessity for an all-inclusive set.

[jotrago]

OK if your search time is acceptable then that's fine.

Re swapping the tapes.

Having the two backup sets is what I expected and shoudl work to your advantage, You can have anly one operation per backupset at a time.

Are you perhaps using Retrospect "Professional" it has only one execution unit (EU). ie can only run one job at a time, thus if you are running a Verify the Backup cannot run until the verify is finished or stopped, and the EU becomes free.

Otherwise with the Server Editions with multiple execution units, your Backup job would start in a second EU, but the Verify job is keeping a lock on the drive, preventing the backup from using it.

 

In which case I suspect the only alternative will be tory the Scheduling feature of teh Verify Job. (If that's available with V7)

You can create a verify Script, set the option to only verify unverified backups, then set a Scheduled time during which the Verify is allowed to run.

Hopefully it will stop at the end of it's sceduled run, allow you to do your backups, and then resume when the schedule starts again.

[jotrago]

Apologies, I just realised this is the Retro Professional forum so I guess that indicates you are using Pro, which only has a single execution unit, thus you can only run one job at a time.

(in my defence I came straight to your post from an email notification and didn't notice which forum it was)