Enterpri se Backup Software That Keeps Your Data Afloat Another particularly thorny problem for enterprise backup systems is databases that need to be up and running 24 hours a day, seven days a week. That's because of the many files associated with the database or application remain open. A similar problem arises when backing up e-mail or groupware systems, most of which are databases in their own right. Most major database vendors have added software application programming interfaces (APIs) or hooks that place the database engine into a maintenance or backup mode that facilitates successful backup of the database or database objects, while maintaining data integrity (see "DBMS Backup Agents: Because the Data Matters," February 1, page 84). Many back up products can retry files that were open during the backups--a valuable option if files couldn't be backed up because of heavy activity or a high number of I/O requests. However, this does not help in the situation where a file is always open when the database or application is up. If your database application doesn't need to be running constantly, you could configure the backup product to run a script or command file that brings the database down in an orderly fashion before the backup and starts it up again once the backup is finished. Another new and interesting option available is the application of RAID software using tape drives instead of disk drives. This is a good solution for backing up a large mission-critical server with a huge amount of data. After all, you don't want to restart a backup job on a 200-GB database just because your tape drive encountered a media defect at about the 189-GB mark. To reflect the setup of most of today's enterprise network environments, we tested four produc ts whose backup server or backup host resides on more than a single NOS platform: Cheyenne Software's ARCserve, IBM Corp.'s ADSTAR Distributed Storage Manager (ADSM), Legato's NetWorker and Seagate Software's Backup Exec. All were tested on NetWare 4.11, Windows NT Server 4.0 and either Solaris 2.5 or AIX 2.1.5. We compared installation and configuration, ease of use, platform and client support, and the various backup options available. Since our testing enterprise contained NetWare, Windows NT and Unix platforms, we selected product lines that covered at least two of these and had an agent for the third. All of the products exhibited individual strengths and weaknesses, but Cheyenne's ARCserve impressed us enough to garner our Editor's Choice award. It has evolved into a cross-platform product line with a comprehensive list of client agents and backup options capable of handling backups for most heterogeneous networks. Cheyenne ARCserve Computer Associates International recently acquired Cheyenne Software, so we probably will have to wait until next year to see what CA and Cheyenne do with their combined storage product lines. For now, though, Cheyenne offers backup server products on Hewlett-Packard Co. HP-UX, IBM Corp. AIX, Microsoft Corp. Windows NT, Novell NetWare, The Santa Cruz Operation SCO Open Server and SCO UnixWare and SunSoft Solaris. All products installed with ease, though ARCserve 6.0 for NetWare required a modification to one of the initialization files to start up properly on NetWare 4.11. This is fixed in Support Pack 1, which is available from Cheyenne's online services. (It's worth noting that Cheyenne has compiled all patches and fixes into an UPDATE.EXE that installs them.) ARCserve offers a substantial number of client agents, all supported by most platforms. However, we felt the product should have been able to perform user-initiated restores fr om remote clients as well as from built-in push-agent technology. The user interface was easy to use and is similar in all ARCserve products, but managing other ARCserve hosts from different NOS platforms was impossible. Though Cheyenne's Unix product trails its NetWare and Windows NT p roducts in options, it does offer a competitive price advantage over IBM's and Legato's Unix products: It's about one-half to one-third the cost of its Unix competition. Cheyenne also has integrated its backup software with its antivirus product on both NetWare and Windows NT. This allows for real-time scanning for viruses, without a performance hit during the actual backups. ARCserve supports hierarchical storage management (HSM) on NetWare and Unix, but not yet on the Windows NT platform.

Remote-Acess Servers Pushed to Their Limits by Bruce Bordman Updated March 7, 1997