In-Depth

Administrators, Start Your Backup Engines ...

The latest in backup software handles the complexity of Windows 2000.

Backup software isn’t the sexiest stuff out there, but it is some of the most important stuff. A shop that doesn’t have solid backups is asking for trouble, or, worse, bankruptcy. Choosing the right product is one of the most important decisions a system or network administrator can make. It should never be taken lightly, as the repercussions are serious.

Backup software’s been around for ages, but it’s not a static market. All four of the Windows 2000-aware products evaluated for this article have been recently revised. If you haven’t looked at the latest software, it may be time to take another gander at these offerings.

One welcome improvement to the backup process is the recognition that restoration from scratch is a time-consuming task; all of these products either have a provision for or include disaster-recovery ability. In an ideal world, you’d pop in a disk to a recovered server, and the rest of the rebuild process would be automatic. Things usually aren’t that smooth (you need a bootable tape drive, such as those manufactured by HP), but the process has improved over the last few years. What used to be an arduous task—reloading the operating system, loading the backup software, making sure that the tape or other device is recognized, restoring an image from tape—has been abbreviated. Now, after loading a diskette or two, you’ll typically be able to restore an image with little or no OS or backup software loaded.

Win2K brings new challenges to the backup equation. Not only are more system and application files continuously open (See “Back up Those Pesky Open Files” for a solution to this issue), but there are also new file types and system resources that create backup problems. All the products I looked at handled Win2K system volumes (SYSVOLs), but when restoring remote servers, information can be lost, particularly if the backup crosses OSes. NTFS version 5 features—such as catalogs, mount points or junction points—and advanced features, such as file grooming or integration with SANs, present additional challenges. Then there’s the problem of backing up the all-important Active Directory (See “The Trouble With Active Directory Backups” for some important information about AD). If you depend on advanced Win2K features (or even if you don’t!) it’s imperative to verify that you can restore the backed-up information successfully before you need it.

Reviewed this month:

Which Backup Software for You?
The battle for market share in the backup niche is fierce. Both ARCserve and Backup Exec offer the ability to read opposing formats, coupled with the suggestion that switching to their backup product would be a worthy upgrade. UltraBac boasts impressive speed, efficiency, and easy-to-use disaster recovery features, while Legato Networker offers the most growth options for the expanding enterprise.

Which one should you pick? I can’t make the choice for you, but I can give you a list of the factors to consider:

  • Does the software support your backup hardware? Each vendor maintains a hardware compatibility list on its Web site.
  • Do you have special databases (such as SQL Server databases or an Exchange message store) that need to be backed up? Select backup software that has an agent for that database, if available, if you need fine-grained control. Consider using St. Bernard’s Open File Manager, if whole file backup is satisfactory.
  • Do you need support for remote workstations or servers? Licensing or version options may increase the cost.
  • If thinking about changing to a new product, consider: How flexible is your IT staff? Are they willing or able to learn a new product?
  • Is backward compatibility a factor? Can you afford to switch to a new tape format?
The Trouble With Active Directory Backups

If you’ve been backing up your Windows 2000 Domain Controller regularly, including backing up Active Directory information, then your domain is safe even if disaster strikes the server. Right?

Wrong—if you haven’t upgraded your DCs to Win2K Service Pack 2. The people at Aelita Software uncovered a nasty bug in Win2K as SP2 was being tested; the bug was subsequently documented in Knowledge Base article Q295932 (support.microsoft.com/support/kb/articles/q295/9/32.asp). The problem occurs when a change in AD causes a checkpoint in the Jet engine used to store the AD information during a backup. Under those circumstances (which are more likely to occur the larger your AD becomes), the backup is corrupted, and restoring it will leave you with a DC that won’t even boot into AD mode.

Even worse, the problem lies in the native backup API exposed by Win2K, so it affects all backup software on the market, Microsoft and third-party alike. Fortunately, the fix is easy: install SP2, or the hot fix mentioned in the KB article. Microsoft recommends that you verify backup functionality and destroy all pre-SP2 backups that contain AD information.

By the way, when you’re backing up AD you should also be aware of the issue raised in KB article Q216993 (support.microsoft.com/support/kb/articles/Q216/9/93.ASP). AD information is timestamped and becomes useless after 60 days. Of course, if you’re not backing up more frequently than once every 60 days, you’ve got serious problems with your process anyhow.
—Mike Gunderloy

Back up Those Pesky Open Files!

St. Bernard’s Open File Manager solves the substantial problem of how to handle open files while doing a backup, without locking users out of applications or creating a backup where files are out of synchronization. OFM worked substantially better then the open file agents included with other backup products and presents many more configuration options than those agents do.

Open File Manager 7.0
St. Bernard Software
(858) 676-2277, www.stbernard.com support@stbernard.com

OFM works automatically and transparently with most backup software, and a single license includes both Windows NT/2000 and NetWare versions. OFM works by recognizing backup read requests for open files. When no partial file writes are pending, it copies the file to a pre-write cache. If a file write goes to the portion of a file being backed up, OFM copies the to-be-changed portion to the cache, and substitutes that portion when the backup software asks for the altered sectors. Thus, the backup has a faithful copy of the file as it looked when the process started. OFM can be told to release this cache before or after a verification pass, will manage groups of files that are updated by a single application, and will recognize remote backup programs—all features most other open file agents lack. Another useful feature lets you use OFM to copy files in use without doing a backup.

Open File Manager
Open File Manager’s console tracks backup activity and the files its processing in real time. You can even alter option settings during a backup. (Click image to view larger version.)

Using OFM, I was able to back up all the open files on my system, even ones the open file agents from UltraBac and BackUp Exec couldn’t handle. OFM does add some overhead, causing other applications to load more slowly while it monitored files. The amount of disk space used for the cache is minimal, because nothing needs to be stored after the backup’s completed. OFM worked extremely well and belongs in any installation where application-specific agents aren’t available, and files are likely to be left open after hours. One other benefit: because you don’t have to lock users out of critical files to do backups, you gain increased backup scheduling flexibility.
—Douglas Mechaber

Each product I looked at has a clearly different personality and strong points. ARCserve boasts the most agents and most comprehensive hardware support. Backup Exec has considerable ease of use and lags only slightly behind ARCserve in terms of hardware and agent support. UltraBac has the most innovative features; if you have the patience to understand the job-scheduling process, it’s a no-nonsense, high-performance product. Legato Networker is enterprise-aware, reflecting its mainframe roots. It grants ultimate control over backup and allows authorized users to submit their own backup and even do their own restore.

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