Handle open files during backup

St. Bernard Software's Open File Manager 5.1 is a network manager's dream. During backup operations, backup applications typically skip open files or attempt to read information in a shared mode. These methods can create a corrupt backup file when another application changes the open file during the backup operation.

Open File Manager lets applications continue operating and lets backup applications access open files, including services such as mail or database servers. When a backup program starts, the software selects a point in time following a brief period of disk inactivity. The subsequent backup copies data to the backup media as of that point in time. When an application makes changes to data on disk while the backup is running, Open File Manager writes to a temporary file the original version of changed data. The software uses the original version of the data when it is written to the backup media, and again during the backup verification phase. Open File Manager does not need to save additional information if an active application updates these records, because the software has already saved the original contents for the backup program to use. The product has an on-the-fly journaling file-system extension to Windows NT and Novell NetWare that maintains the snapshot of changed data only during the backup.

Open File Manager's journaling file system tracks changes users make to open files. Without copying the entire volume, the snapshot or point-in-time view of a disk volume appears as another read-only disk volume, letting you manually copy a point-in-time version of the file. The journaling file system sets up and deletes the snapshot volume as necessary (Synchronize and Unsynchronize, in Open File Manager's terms), such as before a backup operation. The journaling file system must maintain sufficient information to keep the snapshot and the disk volume up-to-date.

Typically, other journaling file systems can reserve half as much space as the original disk volume. Open File Manager's on-the-fly journaling file system uses much less space because backups take less than a day to complete, and the product needs space to hold only the data that has changed since the start of the backup. Journaling file systems typically use a special partition, whereas Open File Manager uses a hidden file.

The product doesn't just work with backup programs. The Open File Copy feature lets the software provide the same service to any application that starts with a designated user account.

Open File Manager is not perfect. Applications update some files, such as the NT Registry, only when the application terminates properly. But even considering this flaw, a program that works so well and transparently is rare.

Installing Open File Manager
I installed Open File Manager in two steps. First, I installed the management applications on an NT system from a pair of 3.5" disks. I started the management applications and an Explorerlike interface appeared on my screen. The left pane in Screen 1 lists NT and NetWare servers on my network. The right panes contain status information about the server selected in the left pane. The bottom right pane shows a log of Open File Manager's actions.

I selected the NT server and clicked Install from the System menu to install the Open File Manager service on my NT server. This process copies the requisite files to the server and sets up the NT service. You must start Open File Manager from the System menu before the software can track files. After you restart NT, the product starts automatically.

Configuring Open File Manager
On NT- and NetWare-based versions of Open File Manager, you manage the service from the management application. A tabbed properties dialog box holds the server's settings. These settings control how the product tracks open files. The General tab provides access to timeouts such as the Write Inactivity Period. You can also set the system log location on this tab. The default settings worked well, and I found no difference in performance when I changed them. The System tab provides basic system information that helps you obtain system configuration of a remote server. The Files tab comprises a list of files or directories in the exclusion list. Open File Manager's files are in this list, as is the NT page file. Finally, the Agents tab lists the supported backup applications with a check box next to those that Open File Manager will monitor. By default, the software selects all options except Open File Copy and Remote Backup. Selecting an application, even if the application doesn't run on the server, doesn't cause overhead because Open File Manager automatically detects the running backup client.

Managing Open File Manager
After I set up Open File Manager, I checked the log occasionally. Graphical summary information would have been more useful than the log. Open File Manager didn't affect the backup speed and didn't influence the performance of other applications or services running on the server.

Documentation and Technical Support
St. Bernard Software relegates documentation to disk. The README file covers the installation process, and the online Help covers operation and management details. The online Help is not extensive, but it is sufficient for general operation.

Do You Need Open File Manager?
Open File Manager is a great program, but it is not for every network administrator. Although open files can be a problem, they are not always a major one. For example, a late-night worker might be editing a document that will not go through a backup because it is in use; however, that worker's system will probably save the file when it performs a daily backup. Also, a backup application that works with other server-based services to properly back up the service database files might be sufficient.

If you have trouble with open files, Open File Manager is definitely the best alternative. It is easy to install and operates quietly in the background. Although the product does not solve all open-file-related problems, it handles most of them.

Open File Manager 5.1
Contact:
St. Bernard Software * 800-782-3762
Web: http://www.stbernard.com
Price: $575
System Requirements:
Windows NT Server 4.0