BE2012: What happens when catalog files are deleted/truncated?

[LameDuck419]

I have found some vague answers to my question in other articles, but I would like a clear answer before I proceed with deleting 4 years worth of catalog files. What happens when the catalog files for a particular piece of media are deleted or truncated? Does the media server:

A) retain the allocated and/or modified date of media, but media must be cataloged before data can be restored from it?

-OR-

B) treat any media without corresponding catalog files as Foreign Media, as though the media server had never seen it before?

Thanks.

[VJware]

When on-disk catalogs are truncated, then specific media which is required for restore must be cataloged prior to the restore.

Have a look @ the last couple of points in this KB - http://www.symantec.com/business/support/index?page=content&id=TECH192529

[LameDuck419]

I understand that, but my question remains unanswered - if the catalog files for a tape are deleted, does Backup Exec still recognize the media as having been previously used by the media server, such as by retaining the allocated or modified date of the media, or will it consider the tape to be foreign media with no knowledge of the date that data was written to it? I've got about 800 offsite tapes with infinite retention and I'd like to know if I need to record the date information of these tapes before I delete the catalog info.

[VJware]

Backup Exec will recognize the media once you run an inventory. It will not treat this media as foreign or imported from another media server.

[LameDuck419]

Again, I understand the media server will recognize the media after running an inventory and/or catalog job on the media.

What about BEFORE I run the inventory? Will Backup Exec know the allocated and/or modified date of the media without running the inventory job? Right now my only record of when a tape was used is what Backup Exec tells me. Will Backup Exec still be able to tell me this after the catalog files for said media are deleted, or do I need to manually record the date the media was used?

[VJware]

Nopes. Unless, an inventory is run, Backup Exec will not know which tape is present in the tape drive. It's not really required to record the dates, as running an inventory will maintain that information.

However yes, its better to have a manual track of which tapes were used for which operation. (Perhaps use a label)

[pkh]

When you introduce an unused tape to BE, then you would have to label it if it does not have barcode label.  After labeling, it would be captured in the BEDB.  If it is a tape which is previously used, but unknown to this media server, then it would be treated as imported media when it inventoried and is captured in the BEDB.  You would have to move this to either the scratch media set or some other media set before you can use it.  When a tape is captured in the BEDB, it remains there until you move it to the Retired Media set and delete it.  All this have nothing to do with whether it is cataloged or not.

You catalog a tape so that the contents of the backup sets on it is known to BE and you can then restore from the contents.  If the catalog is deleted/truncated, you will not be able to restore from the tape because the contents are unknown, but the tape is still in the BEDB and will not be treated as an unknown media.

When you inventory/scan a tape, it is to notify BE that the tape is online.  To restore from it, you need to catalog it if there is no existing catalog of the tape.

When you turn catalog truncation on, the existing catalogs will not be truncated.  Only catalogs created after turning on catalog truncation, will be affected.

[Colin_Weaver]

As long as we are talking about tape, deleting the catalogs from the file system (Catalogs folder) does not affect the media inventory which is held in the database. All deleting the catalogs does is remove the restore selections from being available, so you would have to keep your own records of which tapes were used and when. Because the tapes stay in the inventory, their media set membership and overwrite protection period will be maintained. Note: You will still need an inventory job so that BE knows which slot the tapes have been loaded into.

If however you retire and then delete the tapes from inside Backup Exec (which also removes the catalogs) you will lose the retention settings and then when you inventory the tapes later they will end up in the "Backup Exec and NT Backup" set and be subject to the partial protection setting (and not their original overwrite protection settings). Assuming your intention is to bring back the tapes just for a restore - at this point we would recomend using the write protect tab on the tape itself to avoid mistakes.

In normal operation of Backup Exec ovewriting a tape will remove the older catalog files (against that tape) for you. If you use the catalog tuncate settings then please be aware that changing the setting only has an effect for backup jobs that run after the settings changes it does not retrospectively get rid of existing ones.

Please be very very careful about deleting any catalogs manually from the file system however as the media retention of disk based backup sets (for BE 2012 and BE 2014)  is now based on information in the catalog files and not what is inside the database and therefore any such activity has the potential to cause issues.

[LameDuck419]

...you would have to keep your own records of which tapes were used and when. Because the tapes stay in the inventory, their media set membership and overwrite protection period will be maintained.

 I'm sorry but that statement confuses me a bit... if the overwrite protection period is maintained, wouldn't the modified date also have to be maintained? Which means I wouldn't need manual records of when a tape was last used?

[Colin_Weaver · Accepted solution]

Yes it would be but I am thinking environments where

a) you might be using more than one tape a day

b) might have different servers on different tapes

c) might not backup every server every day.

d) one server might span across more than  one tape.

e) Append jobs are performed

How would you know which tape(s) to use to restore from if the catalogs are gone. Yes you know the modifed date which gievs the date of last append, but perhaps not earlier appends and if multiple tapes show the same data how do you work out which has a specific server or backup set on it?

These scenarios need records outside of Backup Exec.

[LameDuck419]

Thank you! Although the modified date alone usually wouldn't be very helpful, my environment is pretty simple; all backup sets are duplicated tape - even incrementals - with infinite retention. They all use the same media set as well, so the tapes are filled up within 2-3 days of being allocated and then they never expire. I know that seems like a waste of tapes, but what can I say - the "powers that be" have demanded such a setup :)

Thank you all for your input.