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Particularly distinctive among DBMS backup agents, Cheyenne's software lets you back up and restore individual tables. Not even the fine-grained scripting control of Lega to's agent offered this function. Backup and restore of individual tables is a good example of the type of database control we would expect to find in a complete DBMS backup agent. This function is great for those inadvertently dropped tables. Note, however, that restoring individual tables is a questionable proposition as it has the potential to destroy a database's consistency.

Cheyenne's agent installs as two NT services on the client. One provides a connection manager for the backup server, and the other provides a remote procedure call (RPC) agent for the actual data transfer to the backup server. Our installation went smoothly, however, the connection manager did exhibit difficulty connecting to the SQL Server database whenever we changed the SQL Server client configuration. Cheyenne could provide better control or documentation over how the client actually connects to the database.

As another plus, Cheyenne conveniently provides IPX protocol support instead of the default TCP/IP for sites that still need it.

We frequently encountered errors when backing up or restoring under certain circumstances, and in each case, it turned out to be a configuration or setting error. For example, ARCserve, Cheyenne's backup server software, requires a datab ase or table to be dropped before restoring the object. While none of the other agents were any better at this, it seems reasonable to expect that as long as the agent is a full SQL Server client, it should facilitate the process better.

We liked how ARCserve filtered the appropriate backup sessions for viewing depending on the database that was selected for restore. Backup Director lumps together all backup sessions on a media. Cheyenne ARCserve let us find the specific restore session we needed from the entire media catalog much more quickly.

If you're still in the process of selecting an enterprise backup solution and anticipate the need to include a DBMS into the system, ARCserve is a good bet. Cheyenne's present database client support follow s market lines, but it would be more formidable if it could broaden and solidify it.

Legato Systems Database Module for Oracle
Legato's module could be a great addition to a large distributed database installation--if it's a large Oracle installation. The lack of broad database client support limits Legato's applicability, but its overall score is buoyed by its database control and backup flexibility. If you have a large Oracle installation to manage, this module merits installing Legato NetWorker, the company's backup software, even if you're using another enterprise backup system. On the other hand, it's a difficult solution to manage for a workgroup-level Oracle server.

Legato's backup module actually works in conjunction with Oracle's Enterprise Backup Utility (EBU). EBU takes care of the gritty details of enabling Oracle server's backup mode prior to actual backup. It then provides an application programming interface (API) for a separate media manager, such as Legato's module, which acts as the backup repository. The EBU adds another layer of complexity to the setup, whereas with Seagate's Backup Exec, the database access client is built entirely into the backup server.

The primary drawback to the EBU-Legato com bination is the required scripting of backup profiles. Scripting hinders the product's ease of use, but it's also the key to its flexibility. For example, we wrote a script to back individual data files from a table space. Using these scripts, we also set up pre-backup commands to perform exports of specific schemas, which were subsequently included in the backup. We also created restore scripts that restored only individual data files of multifile table spaces. You simply can't get this level of control in a point-and-click interface.