Restore a file that splits across two tapes on a different BE server

[dori_bashan]

Hi

we made a one-time-backup of 5TB of large files - 200 GB each.

we have used our Auto-loader an LTO 5 tapes.

so BE added a few more tapes to the backup once a tape got full.

Now i have the need to restore a specific file that is split across two tapes

But we are making this restore on a different BE server with a stand alone tape

What is the steps i should take?

I have un-checked the "Use Starge Based Catalogs" and the "Request all mediain the sequnce..."

Thanks 

[VJware]

Catalog the tapes on the second BE media server.

Select the file which needs to be restored. Insert the first tape. During the restore operation, BE will prompt the second tape which needs to be inserted. Remove the first tape and insert the second one for the restore job to continue.

[dori_bashan]

Thanks

should i configure the restore when i double click on the backup set of the first tape?

[dori_bashan]

It seems that after i finish the catalog operation of one tape eject the tape and start a second catalog operation

The backup set data of the fitst tape is lost from the ALL MEDIA window.

So after i finish the second tape catalog, i can't see the backup set of the first tape, and thereofre i can not start the restore.

am i missing someting?

[dori_bashan]

Trying to restore the first tape after the second tape catalog was finished result a 

No Backup Sets Found

but i was able to see the backup sets of the first tape after the firat tape catalog was finished and before i started the catlog of the secind tape.

[VJware]

Check the option - Request all media in sequence and then catalog the tapes.

[dori_bashan]

but the media set conatin more than two tapes, and i only want to restote a single file that is is split on two tapes.

the file i want to resore is located on tape 2 and tape 3, and i dont have tape 1 in hand,

so does it mean that if i want to restore a file that is located on tapes 2&3, i must have tape 1 in hand as well?

[Colin_Weaver]

Try turning on the request all media in sequeuce on then run the catalog against specifically the 3rd tape and see if it reads the 2nd tape but does not need the 1st (this is a guess I am not sure if it will work - although would like to know the result)

[dori_bashan]

will try several thing and update.

If i have all the tapes in hand, should i first catalog all the tapes in the media set and only than run the restore?

[pkh]

Yes.

[Colin_Weaver · Accepted solution]

If you have nto got the correct cataloga in place you won't be able to run the restore

The normal proces would be catalog all the tapes that make up the original backup job - howeverthat does assume that you have all the tapes available.

It also assumes that you did not have an infinietely large media family because you kept appending to tapes and never started a backup job as an Overwrite - as such my suggestio of tryomg starting teh catalog job just against teh last taoe is a suggestion but it might fail.

Note a media set a backup set and a media family are completely separate things.

A media set is just a logical group of all tapes that have the same overwrite protection periods and append periods

A Backup set is the backup of a single resource (where a resource is something like C: or System State)

Each backup set has it's own catalog

As such:

- a Backup Job might create more than one backup set

- a tape might contain more then one backup set

- because of what happens when a tape fills up and spans to another tape, a catalog can reference more than one tape and a backup set can use more than one tape.

- a media family is a sequence of tapes where to start a media family, the first tape is specifically overwritten at the very start of a job. The family can then grow every time a tape fills up in the middle of a job and this can happen with the first job fills the first tape, or when following  append jobs use the remaining space. If you continue to use append jobs in theory the family can grow forever, as long as each tape fills up before the append period ends.

- tapes at the beginning of a family can be overwritten early and this could potentially cause a problem if the catalog jobs tries to use a tape that is no longer available - and this bit becomes crucial to your problem, as if the "follow media in sequence" setting does  just follow the sequence for the backup sets on the tape the catalog is aimed at then good, however if it follows every set in the media family then you would nearly always hit a problem unless you keep your media families really small. As such you trying my idea will shows this. 

[dori_bashan]

Thanks for that detailed info.

Assming I have configuured the Media-Set as "Never Overwrite" and "Allow Aappned", and this is a One-Time-Backup, so in this case "Media Set" and "Media Family" are the excat same thing, correct? (assuming we always use more than one tape in a backup)

All my jobs here is either one-time-backup or Full and Incremental when the "full" is configured to "append to media, overwrite is no appendable media..." and the "incremental is configured as "append to media, terminate if no appendable media..."

And both full and incremnatal are using the same media set. so here, again, Media Set and Media Family are the same thing. correct? (again,assuming we always use more than one tape in a backup).

Thanks!

[Colin_Weaver]

No for two reasons:

Tapes can be in the same media set but different media families (each tape can only be on one family and one media set at a time, but both a family and a media set can contain more than one tape)

If the one time backup started as an append it could have added to an existing family and not be the start of a family

The OneTime Backup would have to start as an Overwrite (either because you set it to only start as an Overwrite or because no appendable media was found right at the start of the job)

If this condition is met, and no further jobs appended onto the end, then the backup sets created by that one instance of that one job would all be in a small media family (where the family is made of of the same list of tape names as the job log shows.)

[dori_bashan]

Thanks

i will run a few more tests for the restore and update on the results

[Colin_Weaver]

If you still have problems after the tests, then  I think you should log a formal support case

[dori_bashan]

This is what i have done to solve it:

Keep "Use Storage Based Catalogs" and "Request All Media..." checked.

Run an Inventory job on all the tapes without Catalog.

Run Catalog on the first tape, than BE asked for all the other tapes.

Restore.

Thanks all for all your help