Backup solutions are always a difficult area for IT Departments. Disaster recovery is vital, yet centralized backup software solutions require a lot of hands-on to keep them functioning properly and to ensure all important data is backed up. For several years, I have been working with a disk-to-disk-to-tape model that has been very efficient for fast restores. Of course, this model may not be practical for companies with huge amounts of data, but can be great for companies that can practically utilize SATA RAID arrays for first-level backup (I have been successfully using
Nexsan arrays for several years now). We use a combination of
Ultrium 2 tapes and
LaCie external hard drives for off-campus storage. I have worked primarily with Veritas (now Symantec) Backup Exec. Before Veritas I used CA's ARCServe which was not a very reliable application, at least at that time. I have mixed feelings about Veritas. On the one hand, it has been a fairly reliable application, but when I have faced issues, I have been on my own. Backup Exec tech support is based in India, as is almost all support these days, and I have had a pattern of unskilled, uninterested individuals suggesting rote answers to my issue. In addition to these kind of difficulties, there are other challenges as well. Even with differential or incremental strategies, backups are slow and storage intensive. Compatibility issues can arise between the backup software and Microsoft Windows, especially when Microsoft upgrades their operating system or key enterprise applications such as Exchange or SQL Server.
For these reasons, I am very enthusiastic to try out Microsoft's answer to central backup--Data Protection Manager 2006 (DPM). There are many promising aspects of DPM:
- It is designed on the disk-to-disk-to-tape backup model which provides for very fast restore times.
- DPM only replicates byte-level changes to the backup array. This means that if a user changes a very small part of a large file, only the bytes that were changed are written to the new backup rather than the entire file as happens in traditional differential or incremental backups.
- DPM is a much more reliable solution for open-file backup since it is designed to work in conjunction with Volume Shadow Copy Service (VSS).
- DPM is pretty cheap for the services it is provides. DPM utilizes agent software on up to 50 client servers per DPM server to perform remote backup. The server software costs around $950 and comes with three agent licenses. Each additional agent license costs around $150.
- DPM is Microsoft software working with Microsoft software (Windows). My experiences have shown that this is the best way to go whenever possible.
- You can set up to eight synchronizations to occur per day. This allows you to have up to eight "snapshots" of your files per day.
Before installing DPM, make sure you have a server that meets the minimum requirements (plus some to be realistic) and has at least one unused physical disk. This unused disk will become the designated backup location and must be a free physical disk, not just logical (of course, other disks can be added later). Also, you will need to apply a hotfix (hotfix info is included in the release notes) along with Service Pack 1 if you are running DPM on Windows 2003. Keep in mind that DPM does not support Exchange or SQL Server backups yet, those features are planned for version 2.
To get more information about DPM check out Microsoft's DPM site.