Tape Parallel Processing

[krogerss]

Just curious, but I have noticed that if parallel processing is enabled for a media pool and there are not enough tapes in the library for the given media pool, the remaining job or jobs will have a "WaitingTape" status. This is not unusual. However, if another job finishes the queued job will not proceed with the available tape. It just sits there and says Insert a valid tape into the library. is this expected behavior? Thanks.

[veremin]

However, if another job finishes the queued job will not proceed with the available tape. It just sits there and says Insert a valid tape into the library. is this expected behavior?

Not sure whether I totally got it. Queued job is sitting and waiting for a free tape, even though there free cassettes inserted in library? How does it relate to the finished job? Thanks.

[krogerss]

Well say you have 3 tape jobs start at the same time and allowed to use 3 drives. However, there are only 2 tapes in the library. One of the jobs will notify you to "Insert a tape to continue." If I'm not able to add another tape to the library, I would have thought that the queued job would have started when one of the other jobs finished since that tape would be available. Thanks.

[veremin]

So, you have two tapes inserted in library and three running tape jobs. Two tape jobs take two existing tapes, write data to them. One of them finishes, leaves written media in the library. So, you want the third (queued one) job to take this already written cassette and leverage it?

If so, it's not possible by design, different jobs create and use different independent media sets and cannot share the very same media.

Thanks.

[krogerss]

So this is specifically for parallel processing with tapes, right? I didn't realize media set creation was different with this enabled. Thanks.

[veremin]

So this is specifically for parallel processing with tapes, right?

Nope, as different jobs typically use different tapes to write data to. By the way, what media set creation and retention settings does the given media pool have? Thanks.

[krogerss]

Media set creation is at 3pm everyday. Retention is set to 28 days.

[veremin]

Got it. What you see is an expected behaviour, so, make sure to stuff a library with appropriate number of tapes prior to jobs' execution. Thanks.