Tape ejects out issue

[Holloween]

Dear community,

I have a weird issue here. I have created a media set with 1 hour as the OPP and infinite as the append period.

Backup of the hypver V machine with multiple VMs runs daily from Monday to Friday @ 10pm.

The issue here is, on every Friday night, the tape will get ejected out. Is this behaviour a bug? It should overwrite the first backup inside the tape isnt it?

After I cleared the "eject tape" bubble, I re-insert the tape and perform a manual backup. (Right click > Run job now) the backup works!

I have no clue on why this is happening. Anyone out there faces the same issue?

My SEP version is 2012 SP2 (the latest service pack)

[Holloween]

I think I may have found the issue:

Can anyone verify if my understandings is correct:

Scenario (Values here are fake):

- I have a 1TB tape.

- Backup job takes about 210GB worth of space

- Backup runs Mon - Fri.

- OPP set to 1 hour, APP infinite

Base on the above scenario, after thursday, a total of 840GB data was backup. (210 x 4)

Tape is left with 160GB free space

My original understandings: On Friday, since there is not enough space available to backup the whole of 210GB data, it will overwrite the first copy in the tape. 

Apparently, this is not the case, on Friday, backup will still write to the remaining 160GB of the tape. And for the last 50GB, it detects that the tape doesnt have enough space, therefore it ejects the tape and prompts for the next one.

My new understandings:

Backup Exec is not smart enough to detect the remaining space. It will continue to write even if there is 10GB of space in the tape. You will need to set the append period such that it cannot append anymore and is forced to overwrite.

So to summarise, in order to solve this issue, we cannot set the APP to infinite.

Now this brings me to another question, after clearing the "Tape eject" bubble, and after re-inserting the same tape and I run the same backup job. It works. Shouldnt it fail as well?

[CraigV · Accepted solution]

...BE will not expire sections of a tape...it could do this with disk, but not tape as that is written sequentially. So you are correct in assuming that the tape fills up, and then asks for a new tape to be inserted after ejecting the current tape. No way around this. I know that ARCserve is the same, whilst IBM TSM expires sections of tape (but that's another story completely!)...

Set the Append period lower (say 5 days) and see if this allows the tape to be overwritten.

the other option is to buy more tapes...although not always possible due to finances, this would allow you to keep multiple separate copies, and maintain them for a longer period.

If you want to use only 1 tape, continue to set the Append period lower until it allows the tape to be overwritten when you want it to be!

Thanks!

[pkh · Accepted solution]

No.  If you have exceeded the 1 hr. protection period, the tape would be overwritten.  This is why it is bad practice to set such a short OPP.  In fact, you get a warning when you set the OPP to 1 hour.

[Holloween]

Thanks both CraigV for answering the question on "BE will not expire sections on tape" and pkh on answering my last question. 

Symantec forums rocks!

[Donald_Eady]

Not too sure as to why the tape is ejecting only on friday nights... Are there any other jobs that may be running on Friday prior to this job that are set to Eject the media after the job completes. 

[Holloween]

Apologies if I didnt state my problem clearly. But I have found out the cause and so I updated in my second post just to confirm my understanding, in which CraigV and pkh have both give good advice.

The problem was:

It was ejecting on friday nights because after the backup job on Thursday night, the tape itself does not have enough space for Friday backup.

But since APP is set to infinite, symantec BE will try to append to the tape even if there is not enough available space.

So when it runs out of space, BE ejects the tape and prompts for another media.