Removing Robotic library slot from Partition

[wajeeh_r]

Dear All,

I've 1/8 G2 autoloader with total 8 slots. I created partitions in this and assigned slot 2,3 to One partition. This partition is associated to Media Set 'Weekly' which is weekly full backup job. I designated the two slots and this partition only for exchange server information store backup. Since our environment is small the data which is taken as full backup on tape is only near 130GB (Full weekly backup) while the capacity of tape is 2.3 TB.

I realized it does not make sense to keep other tape i.e. slot 3 also assigned to this partition. My current settings for this media set is for OPP as 4weeks and append 'allow infinite'.

Thought coming to my mind to release one slot i.e. 3 from this partition but concerned about the exchange backup job which is assigned on this partition which presently consists of two slots. What will be the impact ? the job will continue to run on Slot 2 tape ? What is the correct procedure in Backup Exec to get this done.

Please advise and share.

Kind Regards,

[Colin_Weaver]

You will temporarily have to assign the jobs to the whole of the library, then adjust the partitions and then assign each job back to the correct/new partition

[pkh · Accepted solution]

If you have only one slot in your partition, then you must ensure that you NEVER write to the end of the tape in that single slot.  If you do write to the end of the tape and the job requires another overwritable tape for it to continue, then there is no way you can introduce this tape into the library and the job will fail.

[wajeeh_r]

Hello phk,

thank you for your reply. Yes, I am thinking to assign one slot to my partition keeping exchange data in mind which is not huge.

So, you are saying if another overwritable tape is required the job will fail since only one slot in partition. In my settings for media set in which this slot is currently associated is having OPP '4weeks' and append 'allow infinite' , So I am thinking that when the end of tape is reached the first job which was written must have passed 4 weeks time and that space will be available to over write, this makes sense to you ? OR I am wrong ?

Thanks,

[pkh]

No. This is not correct. The OPP starts from the END of the last job to write to the tape, not the first job

[wajeeh_r]

So, it means all jobs starting from 1st job, 2nd job which already passed the defined OPP time will not be available to overwrite, and will only be available to over write when LAST written job at the end of tape, the time complete its 4 weeks ?

So, what you suggest to me I should not remove the second tape from this partition ?

OR how I handle this because like I mentioned just because data is small I wanted to avoid keeping second tape assigned there.

I will wait for your response.

[pkh]

No. The OPP starts from the end of the last job to write to the tape. This job may not necessarily be the job that writes to the end of the tape. For example, you have an OPP of 2 days. After Monday's job the tape would be protected until Wednesday. After Tuesday's job the tape would be protected until Thursday and so on. Tuesday's job may only write to half the tape. Whether you remove the second partition is up to you. I just want you to know the implication of doing so If you don't use partitions, then BE is free to fetch tapes from other slots You might want to read my article below https://www-secure.symantec.com/connect/articles/must-mondays-backup-be-monday-tape

[wajeeh_r]

Ok, I understand OPP starts from the end of the last job written to tape, so even previous other jobs exist on same tape and their OPP finished, the tape is still unavailable to me to write any thing due to last job time extension of OPP, this is correct?

If this is correct then it is not suitable to remove the second tape from the robotic library partition which currently holds two tapes.

I've also created one partition and associated it to media set 'differential daily' and it have one tape. Now the settings for this media set is OPP '6 days' and Append 'Allow infinite', So, here what will happen is after end is reached for tape with last job it will be locked for 6 days, can I do something here with append period , since I only have one tape for differential which is more then enough for me for differential data, no sense of adding second tape for differential purpose.

[wajeeh_r]

Dear Pkh,

Can you please just see my last post and give me quick answer, sorry but still little confusion that OPP locks complete tape after any last written job OR it only locks last backupset written for OPP period

e.g. for my account server I ran full backup on 1st Jan and OPP is set for 7 days, the next Full JOB ran on 7th JAN so by this time for first full job OPP is finished, still that space occupied by first job is locked in tape ? OR only for second full job which ran on 7th Jan and is valid upto 14th Jan

and please assist me for my differential tape which is one tape in the partition like I mentioned in last post

[pkh]

The entire tape will be overwritten, not just the last backup set.

For your differential tape, as long as you do not reach the end of the tape, you are o.k. When you reach the end of the tape your job would require an overwritable tape and it will fail because you cannot put an overwritable tape into the partition. There is no way around this problem. A second overwritable tape is required.

*EDIT*

To understand things better, do read the Media Management chapter in the Admin Guide which can be found in the BE installation directory.  Also, read this document

http://www.symantec.com/business/support/index?page=content&id=TECH5459

*END EDIT*

[wajeeh_r]

Thank you very much for explaining me this useful information. Now I am clear for OPP and I've gone through the small video explaining the basics

Since, I only have one tape to be used for differental and all my differential fits easily to it for the whole week even for two weeks, and for differential only last differential copy is usable, Can I set the OPP to 22 hours ? so the tape is again available to overwrite, how about append ? set it to 1 day ?

Is this right to do so ?

[pkh]

Setting the OPP and AP is just one aspect. You also need to determine when to set your job to overwrite the tape