IT Services



Troubleshooting Slow Backups


Contents

TSM uses a computer's resources very intensively, both while backing up and while restoring. In certain extreme cases, very slow long-running backups have to be cut off - this is unfortunately necessary because we have to share the HFS's resources among a large number of users.

If you receive an e-mail telling you that your backup has been cut off due to a slow or long-running session, the problem is most likely to be one of the following.



1. Connecting from outside the wired university network



1.1. Wireless backup

If you are backing up via a wireless connection then the speed will be much slower than that of a wired connection. For further information please see our page on wireless backups for a table showing comparative speeds.

If you have a large amount of data to back up, then you may find that you need to do so within the university network. If possible, try backing up via a wired connection to see if this fixes the speed problem. You may be able to do this in your college, department or in a university library; if not, wired connections are available to use in the IT Services Help Centre. Since TSM only needs to back up new/changed data, you may find that the problem goes away after your initial backup.

If you are only able to back up over a wireless connection, then limit what you back up by only selecting those files that you need to back up; this is quicker than selecting your whole machine for backup. Please see further our instructions for running manual backups on Windows, Mac, Linux or Solaris.



1.2. VPN-based backup

A home broadband connection is not generally sufficient for backing up large amounts of data. For further information please see our page on VPN-based backup for a table showing comparative speeds.

If you have a large amount of data to back up, then you will need to do so within the university network. If possible, try backing up via a wired connection on the university network to see if this fixes the problem. You may be able to do this in your college, department or in a university library; if not, wired connections are available to use in the IT Services Help Centre. Since TSM only needs to back up new/changed data, you may find that the problem goes away after your initial backup.

If you are only able to back up from outside the university, then limit what you back up by only selecting those files that you need to back up; this is quicker than selecting your whole machine for backup. Please see further our instructions for running manual backups on Windows, Mac, Linux or Solaris.



2. Local network problems

Problems with TSM that are caused by network issues can be difficult to identify, since the problem may be manifested on one or many machines, and since the network may seem otherwise unproblematic. In cases where TSM may be affected by a network issue, we recommend checking the following.



2.1. Faulty or misconfigured network connection

If a group of machines on one or more subnets are backing up very slowly, then local IT support staff should check that there have been no recent changes to network infrastructure, including network switches and cabling. The network must be set to full-duplex. If this is not the case then, when TSM tries to upload data, backup performance is likely to be severely affected.



2.2. Firewalls

Although firewalls do not usually affect connections to the HFS, there are certain settings which can cause problems. On this please see further our section on trouble-shooting firewall-related issues.



3. Intensive process running

TSM makes intensive use of a computer's processor, RAM and hard disk. It is recommended that you not run a backup while you are running another resource-heavy process such as data-processing, because this may significantly impede your backups.



4. Specific file(s) causing problems

There are several ways in which the data on your disk(s) can contribute to backups running slowly.



5. Out-of-date TSM version

Two old versions of TSM, TSM 5.4.1.2 and TSM 5.5.0.0, have a performance issue which is manifested when a Mac, Linux, Solaris or Netware machine has many files (usually several million) in one partition. If you are running one of these versions, then please upgrade your TSM software.

To find out which version of TSM you have, see Which version of TSM am I running?. For instructions on how to download and install the latest version of TSM, please see our page on downloading the TSM software for the HFS backup service.



6. Further help

If you have worked through the above list and have not succeeded in fixing the problem, please find your configuration file(s) and logs (via our lists under Where are the TSM configuration and log files located?), and send them to the HFS Team via the Help Centre.