Backup Inquiry Regarding Overwritable Tapes

[DamienSCP]

I am in the process of modifying an existing backup configuration we have in house to have it run more efficiently.  I running across an implementation problem, that is keeping me from having successful backups every night.

Scenario:

I have 5 Jobs Running on a daily basis.  4 of these jobs fill up about 1/2 ofa 400gb tape (lets call this Tape A). The 5th job usually continues off Tape A onto Tape B.  This job is large 375gb.  The 4 jobs run from 7pm and usually finishes around 3am.  The 5th job runs from 3am and finishes at 3pm.  Our tapes are sent offsite every day at 10am.

Problem:

The 5th Job takes a very long time to complete.  Usually what happens is that i have to cancel the 5th job, prior to 10am so that i can send the tape offsite (at 10am, the 5th job is still running on Tape A).  This is a problem because i sent the tape with only 4 of the 5 jobs fully backed up... 

Question:

Is it possible to:

1. Force the 5th Job to start on a totally new tape (TAPE B in this case), after the 4th job has completed successfully?

2. Is there a way to remove TAPE A (from an Exabyte Library) while Tape B is being "written to".  This way i can send the complete backups of the first 4 jobs out before 10am, and i once the 5th job is finished on Tape B, i can send that out the next morning?

regards,

Damien

[Ken_Putnam]

1) Certainly.  Either write the 5th job as an Overwrite to a different media set, or make it an Overwrite Job to the same media set

2) Not sure.  It probably depends on the library/loader itself.  Check the User Guide

If you have more than one tape device, you might also consider running jobs 1-4 and 5 at the same time.  Throughput for the first set will go down somewhat, but depending on your infrastructure, you may get both finished before you ship tapes off site in the morning.

Message Edited by Ken Putnam on 02-03-2009 10:14 AM

[DamienSCP]

Thanks for the reply Ken.  Im still not sure how "overwrite" will resolve my 1st issue.  All of my tapes are in the same Media set.  Job 5 is set to "Append to Media" and what happens is that is starts off on Tape A and ends on Tape B.  Are you saying that if i set Job 5 to "overwrite media", it will start on a new tape in the media set?

regards,

Damien

[Ken_Putnam]

Are you saying that if i set Job 5 to "overwrite media", it will start on a new tape in the media set?

that is correct

[DamienSCP]

Excellent!  Just 1 more question.  Based on what is stated in the Administrator Guide, if the Media Set has an overwrite protection of 1 hour, that means that the specific media is protected starting from the last write to it.  Therefore, can i assume that after Job 4 on tape A is complete, Job 5 will start on Tape B (Or another "non-overwrite" protected tape because of the overwrite protection on Tape A

[Ken_Putnam]

again correct.

If you want to keep you data for 5 weeks, I'd change the OPP to 28 days.  If you leave it at 1hr, and later run a one time or special job, it could see the tape as expired and overwrite it