A New Kind of Home Computer: Windows Home Server Preview

WHS As A Backup Suite, Cont

As for restoring data, WHS comes with two options. The first is the traditional per-file restore, which can only be handled by a client. When a user/client wants to restore a file, they will pick the date/backup from which they want to restore the file, at which point the connector software will mount a dynamically-generated volume that is the contents of the client as of that backup. At this point the user can copy over files from the backup volume to their hard drive.

For a more complete restore, such as in the case of a catastrophic failure or those looking to use WHS as an image backup server, WHS ships with a live-restore CD. When the restore CD is inserted into a computer, the affected machine can connect to the WHS server and select a whole backup to restore. Since the operating system is included in the backup, it is also included in the restore, returning the machine to the same state it was in as of the backup. This process does however wipe the client's hard drive in the process, so it's not something that can be used leisurely. Power users that will be using it as a way to image and restore machines will especially appreciate the ability to restore to volumes of arbitrary size, and while Microsoft isn't pushing the imaging ability hard, it's one the best features of WHS.

There are a few caveats with the backup features of WHS that bear mentioning however. First and foremost only machines running Windows XP SP2 or Windows Vista x86 can be backed up. Older versions of Windows are not supported, and more surprisingly x64 versions of Windows are not supported. The WHS development team has cited the need to write drivers for the backup/restore abilities as the reason for the latter limitation, as they did not have the time to write a good set of drivers for both x86 and x64, so x64 support is not included for now. Unfortunately we don't have a good idea when such support will arrive; the development team for WHS is working on writing a version of the software for x64, but they are not saying when it might be ready.

Hardware constraints also need to be considered. Backups are transfer intensive, so anything less than a gigabit Ethernet link will cause the network to be the bottleneck. This is especially problematic for wireless links, which under 802.11g are practically capped to less than 6MB/sec (and realistically top out at under 4MB/sec), a fraction of the transfer rate of a hard drive. Microsoft highly recommends at least a 100Mb Ethernet link (forgoing a recommendation for wireless entirely), but wireless will work at the cost of being especially slow when WHS needs to do another full backup because it is ready to throw out the old one.

Last, there is the issue of doing backups at convenient times. A machine needs to be fully-on to be backed up, and WHS only has a limited ability to deal with AWOL machines and deal with machines that aren't currently on; it (or rather the connector) can wake up sleeping computers, but does not have a wake-on-LAN feature for waking up computers that are shut off entirely. An add-on exists that can handle this, but the only reliable way of backing up a machine at night is to leave it on or put it to sleep instead of turning it off. Sleeping however can be more problematic on an enthusiast computer than an OEM-built one.

With that said, it's very clear that Microsoft has put a lot of thought and their best technologies into the backup feature of WHS. Although this isn't a round up where we can adequately and fairly compare all the major backup software suites, we will say that we're very impressed with what WHS can do here. The backup features alone can sell WHS if the price is right as is the number of machines.