Product Reviews

As storage capacities grow, traditional backup systems are finding it more difficult to get the job done. PresStore is a client-server enterprise standard backup, archive and synchronising solution that really gets to grips with the problems of dealing with large quantities of data, solving the problems with an admin-friendly approach.

The main trick up its sleeve is Index Referenced Backup. During an incremental backup, PresStore records not just the changed files, but those files that have been deleted or moved as well - think disk cloning for tape drives. Essentially, it can restore your data to any point in time by combining previous full and incremental backups. Moreover, you can interrupt a backup at any time, with the data already written usefully stored so you can restart the backup later on. In fact, you can even give a backup process a time window in which to run, knowing that by the end of the week you should have a complete backup. For clients who connect sporadically (MacBook users, for example), backup can be set to begin as soon as they connect to the network; and when they disconnect, PresStore will update the index to that point - essentially, providing interruptible backup for laptop users.

Incremental backups are great, but sometimes you like to know you have a full backup to hand on a single set of media. Using the index, PresStore can create a synthetic backup, running back through the incremental backups to produce a new full backup from existing media. This means you can effectively run a full backup offline.

The software is designed to work with automated jukeboxes, as well as the usual variety of backup media: single tape drives, optical drives (including Blu-ray), and San or Nas devices. It supports barcode inventories for those jukeboxes with the necessary hardware. PresStore can read from different servers (with network data compression),

ADVERTISEMENT

and write to different media devices in parallel (keeping track of things with the index), improving the speed of the backup. For safety-conscious users, it can also write the same data to two different devices at the same time - not just at the file level, but also at the block level. So when writing to two devices, they're guaranteed to be identical.

Thanks to the indexing, and plan- and block-level cloning ability, PresStore also offers two unusual features: volume regeneration, where a missing or faulty medium can be reconstructed from the cloned media; and volume migration, which allows you to take backups made on an older tape drive, say, and move it onto a newer drive that uses different media, which is great for updating your hardware without losing access to previous archives.

PresStore also handles synchronisation. Its use of TCP/IP and compression makes it possible to sync folders across the Internet, between offices. It uses very short synchronising intervals to get near real-time duplication, so your office in Hong Kong can have effective access to the images you've just saved to your server in London.

The application is beautifully cross-platform. Not only will it run on Mac OS X, Sun Solaris, RedHat Linux, SuSE Linux, and, yes, even Windows, but it also handles OS-specific metadata such as resource and data forks, Finder info, X-Serve Access Control Lists settings and permissions. Mac installation is via a standard installer package: once the background applications are installed, its built-in web server means everything is controlled from your web browser - Firefox or Safari.

The web interface is reminiscent of OS 9 in terms of look and feel, but functionally there's no compromise. Despite being web based, the interface is so shot through with Ajax widgets (menu bars, contextual menus, revealable console views) that you'd be forgiven for forgetting you were in a browser at all. Most importantly, restoring a file is pretty much a point-and-click affair.

The system is highly modular and your key determines which features you have access to. As well as the main user, you can add more clients, whose interface and login page can be tailored so they only get to see what the admin wants them to. Help is available from the support sidebar, which gives you access to online manuals, online technical support requests and updates. All in all, PresStore 2.3 is an excellent solution that we can highly recommend.