| Written by Hywel Mallett & Mitch Ross,
on 04-03-2007 22:48
|
Backups always seem to take too long. There are several things you can check or change to speed up your backup. This article will deal with general checks you can make.
Firstly you should make sure that your backup hardware is working properly, and at full speed. If using backup to disk, then you need to move on to performance optimising. However, if using a tape drive, then most tape drive manufacturers provide a utility to verify the installation and run performance tests. You should have an idea of the expected performance from the tape drive specifications. If you aren't getting the expected performance, consult the tape manufacturer. Make sure you have a SCSI card that can handle the maximum throughput. LTO3 requires SCSI 320 to get the best out of it. Make sure that any backup to tape jobs use hardware compression if possible, as this will speed up the backup rate. If your backup hardware is working properly, you need to make sure that your data can get from its location to the media server as quickly as possible. If you have fast backup hardware you will easily saturate a 100Mb/s network. You need a 1000Mb/s network to break through the 600MB/min backup rate barrier. A common tip is to stop your network cards from auto-negotiating speeds and force them to the highest speed supported, though in many cases this isn't needed. If your backup data passes over your production network, and your production network is in use during the backup window, this will slow backup speeds as well as impacting on the user experience. In this case, you may wish to create a separate network to run your backups over. If you are trying to determine where a bottleneck lies, you might try creating a job which doesn't use the suspect component. Eg, if you suspect your network is the bottleneck, first copy the data locally, then back that up and compare speeds. If you suspect the tape hardware is the bottleneck, run a backup to disk job and compare speeds. If you suspect there is an issue with Backup Exec, run a backup using NTbackup. Make sure that nothing is interfering with your backup data. A common suspect is antivirus software. If every file you backup is being virus checked you can lose a lot of performance. You might want to consider not having your antivirus software running during the backup. If your performance level changes, your first question should be "What changed?". Sometimes patches from Symantec or an application vendor can adversely affect performance. Finally, accept that there is a limit to how fast a backup can go. This also depends upon your data type. If you are backing up data that consists of a few large files which compress well, then you may see great backup speeds. If the backup is of lots of small files (eg. thousands of Windows shortcut files) there is an overhead which can greatly reduce the backup rate. If everything is working OK, the next step might be to try optimising your backup. Last update : 29-04-2007 22:35
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