What's the connection between the Oracle server and the TSM server? Whether multiple channels not multiplexed, or, one channel with multiplexing (or some other combination) may not speed up the backup/restore depending on the weakest link (source disks, lan, disk pool target disks, tape). Our DBA's performed multiple tests to figure out the best speed. Once you hit a throughput limit, I don't think the number of channels or multiplexing would matter.
I agree, if you stage to a disk and migrate, then I know of no way to control what tapes multiple TDP files would be placed on. Since we TDPO direct to tape via storage agents, we can always give a restore the same channels the backup used. I don't know how the number of backup channels would effect a restore if all the files were on the same tape. This is confusing to me. Rick -----Original Message----- From: ADSM: Dist Stor Manager [mailto:ADSM-L@VM.MARIST.EDU] On Behalf Of Shawn Drew Sent: Friday, November 11, 2016 9:01 AM To: ADSM-L@VM.MARIST.EDU Subject: *EXTERNAL* TDP Oracle best practice I’m looking for best practice advice for TDP for Oracle with regards to # of channels. If you have a classic TSM environment with a disk pool that migrates to tape, it would seem that using one-channel for TDPO backups makes the most sense to prevent the case where multi-channel files get migrated to the same tape. Our DBAs are quite opposed to using only one channel (particularly large multi-TB databases) but I can’t find any official best practice statement from IBM that I can use as a response. Unfortunately IBM support worded it “you might want to only use one-channel” which didn’t sound strong enough for our DBAs. There is no “reverse-collocation” to ensure the data ends up on different tapes, as far as I know, so what is the best practice for backing up Oracle data in an environment with data migrations? -Thanks Shawn ----------------------------------------- The information contained in this message is intended only for the personal and confidential use of the recipient(s) named above. If the reader of this message is not the intended recipient or an agent responsible for delivering it to the intended recipient, you are hereby notified that you have received this document in error and that any review, dissemination, distribution, or copying of this message is strictly prohibited. If you have received this communication in error, please notify us immediately, and delete the original message.
