Replica Network Data Manager 2.0

When you assess backup products for your environment, you should put Stac's Replica Network Data Manager (NDM) 2.0 high on the list of potential solutions. I installed the Replica NDM server on a Windows NT server, and I installed the client and the management console on several NT workstations. The installations were simple, and only the server required a reboot. The server installation automatically creates a shared folder for end users to install the client software from.

At first I wasn't sure how to use the software because the Start menu's program group contained only the Help file. The easiest way to use the software is from the integrated options in Windows Explorer. To manually start a backup from Windows Explorer, I right-clicked a drive volume icon and selected Back Up from the pop-up menu.

Restoring files was simple. A Replica NDM icon appears on the desktop and in Windows Explorer, as Screen 1 shows. I selected the Replica NDM icon and browsed the storage server's directory to locate the file to recover. Then, I right-clicked the file, selected Recover from the pop-up menu, used the Browse for Folder pop-up menu to select a folder to recover the file to, and clicked OK. You can right-click a drive volume and select Properties from the pop-up menu to list and restore earlier backup versions.

To perform administrative tasks, you use the management console, which is a Microsoft Management Console (MMC) snap-in. I scheduled backups, created disaster-recovery disks, and set properties and user rights. You can place client computers in groups and back the computers up as a unit.

Replica NDM keeps detailed information about backed-up files to avoid file duplication. Although every client might have Microsoft Office installed locally, the software backs up winword.exe once for the entire system. After a user changes a file, Replica NDM stores only the changed portion of the file. The software also applies Stac's data-compression algorithms to condense the file.

My development system with 5.1GB of data consisted of an NT workstation running Microsoft Visual Studio (VS) Enterprise Edition, NT 4.0 Option Pack, Office, and several relational database management systems (RDBMSs). Although a 450MHz Pentium II processor with 128MB of memory powered the system, performance seemed sluggish during the backup. The initial backup took 2.5 hours, and successive backups took no longer than 4 minutes. Administrators can schedule remote user backups and configure a message to display before a backup begins so that users can suppress the backup.

To test Replica NDM's disaster-recovery features, I formatted a client's hard disk and simulated a disk failure. To restore the hard disk with the latest backup, I created 3.5" disaster-recovery disks, booted the client from the disks, and stepped through a few menus with choices such as whether to format the hard disks. I selected the defaults, and the recovery continued from the network without my involvement. You can also place the backup and recovery data on a CD-ROM and use the CD-ROM as a recovery disk.

Replica NDM impressed me because it made each backup look like a full backup, although the backups were partial. The product effectively hid its complexity and was easy for me to use as an end user and an administrator. Without question, this product is worth the cost.

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