[Veritas-bu] Disk staging units in 5.1 MP4: Max Concurrent Jobs?
Hello, I'm trying to use a disk staging storage unit under 5.1 MP4, and am wondering how to interpret the maximum conconcurrent jobs attribute. I assumed it controlled the number of concurrent jobs allowed to write to the disk staging storage unit during stage 1, and some experimentation does seem to confirm that. However, I would have thought Stage 2 (relocation) would have had the number of concurrent duplication jobs limited by maximum concurrent drives setting of the final destination storage unit. I have 2 tape drives in my final destination storage unit, max concurrent drives set to 2, and instead of 2 orderly duplication jobs, I saw 4, with many 134 errors as they contended for tape drives. Or at least, I would have expected the duplications to quietly wait their turns for drives as they do when I start them manually from a conventional disk storage unit. I found that when I reduced the max concurrent jobs of my disk staging storage unit to 2, that seems to limit the duplication jobs to 2. What's going on here? How do I allow many disk-to-disk jobs in stage 1, but only one disk-to-tape job per tape drive in stage 2? -- Phil Rand [EMAIL PROTECTED] ___ Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu
Re: [Veritas-bu] Disk staging units in 5.1 MP4: Max Concurrent Jobs?
It did indeed. Thanks! On 3/29/06, Stephens, John [EMAIL PROTECTED] wrote: This should explain it. http://support.veritas.com/docs/280398 John D Stephens [EMAIL PROTECTED] -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Phil Rand Sent: Wednesday, March 29, 2006 3:19 PM To: veritas-bu@mailman.eng.auburn.edu Subject: [Veritas-bu] Disk staging units in 5.1 MP4: Max Concurrent Jobs? Hello, I'm trying to use a disk staging storage unit under 5.1 MP4, and am wondering how to interpret the maximum conconcurrent jobs attribute. I assumed it controlled the number of concurrent jobs allowed to write to the disk staging storage unit during stage 1, and some experimentation does seem to confirm that. However, I would have thought Stage 2 (relocation) would have had the number of concurrent duplication jobs limited by maximum concurrent drives setting of the final destination storage unit. I have 2 tape drives in my final destination storage unit, max concurrent drives set to 2, and instead of 2 orderly duplication jobs, I saw 4, with many 134 errors as they contended for tape drives. Or at least, I would have expected the duplications to quietly wait their turns for drives as they do when I start them manually from a conventional disk storage unit. I found that when I reduced the max concurrent jobs of my disk staging storage unit to 2, that seems to limit the duplication jobs to 2. What's going on here? How do I allow many disk-to-disk jobs in stage 1, but only one disk-to-tape job per tape drive in stage 2? -- Phil Rand [EMAIL PROTECTED] ___ Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu -- Phil Rand [EMAIL PROTECTED] ___ Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu
Re: [Veritas-bu] on the subject of disk based backups....
I'm curious: Why do people use different volume pools? We have one pool for Exchange backups, and three others to go with our Iron Mountain weekly rotations, but I'm not sure what that's buying us. For tracking Iron Mountain boxes, we use volume groups, so the three pools for that are redundant. It's nice to be able to easily break out the Exchange tapes, but there are other ways of getting that information. So I don't think the case for separate volume pools is all that compelling for us. How do other folks use them? other than being able to track easily how much On 3/23/06, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: Hi Paul, from my experience what you say about DSSU is incorrect, a single DSSU cannot stage the data off to multiple tape tape pools - if you have a requirement to stage to different tape pools you need to have a at least one DSSU per tape pool, cheers Andy. Paul Keating [EMAIL PROTECTED] Sent by: [EMAIL PROTECTED] 23/03/2006 13:05 To:veritas-bu@mailman.eng.auburn.edu cc: Subject:[Veritas-bu] on the subject of disk based backups I'm also interested in thoughts regarding VTL vs DSSU. DSSU interests me mostly because I can write multiple jobs at once without any regard for tape pool, mpx or not, retention, etc. ...then it all gets sorted out to appropriate tapes during the destaging VTL still presents itself to NBU as a tape, so each virtual tape drive must be licensed with Veritas, in additional to the physical tape drives (unless the VTL is run inline, though there could be issues there regarding estimated compression, etc.) Just a couple things off the top of my head. Just wondering who is using DSSU, adn who is using VTL, adn why you made that choiceie.what were the key requirements for your environment that made one option better than the other. Paul -- Phil Rand[EMAIL PROTECTED]
