SAN/Tivoli performance issues
My question has to do with a SAN/Tivoli storage environment where the storage manager initiates the connection to the client for backup. When the initial backup begins, the data rate is large and immediate but then degradation sets in and the backup data rate comes to a screeching slow down. The backup runs for hours/days and is eventually terminated because it never completes.
Having said that, there are other servers in the same network that perform its backups in less than an hour or a little more with the same or close to the same amount of data.
Since the data is being pulled from the server could there be too much contention at the storage manager level? Is it possible that the position of the servers on the network is at issue?
Performance problems could be any number of things. But, the way you describe this scenario it sounds like there is something pathological going on, beyond just network congestion.
I guess the system in question is a Windows system? They have slower
I/O rates than Unix systems and more problems with memory utilization
It could be a bad network card, other applications running in either the client or the network, overloaded networking equipment dropping packets or NICs that can't handle the load. Just about anything in the path is suspicious.
You will need to start isolating variables as much as possible. Can the client be backed up to a directly attached tape drive? If so, what is performance of that like? Then, what happens when you try to FTP between systems? Are there alternative network paths that could be tried? All those variables are things to try to figure out where the problem is.
Be careful, the first problem you find might just be covering up another one. Don't forget to check all system software levels for patches and compatibility with the backup software and agents and all drivers running in both systems.
Best of luck.
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This was first published in January 2004