CrashPlan’s unique feature is the “you show me yours and I’ll show you mine” of backup. What I’m talking about is the ability to backup to a friend’s computer, by mutual consent, which probably means letting your friend backup to your computer. This feature is part of CrashPlan’s emphasis on targeting multiple backup destinations from a single application. CrashPlan offers four classes of backup destination.
If you and a friend each have a CrashPlan account, you can exchange friend codes. When you enter a friend code into your copy of CrashPlan, you gain the ability to backup to your friend’s computer over the internet. This gives you offsite backup without the need to pay for online storage. You have to rely on your friend’s computer being online during the times when you want to perform backups, but as long as there’s enough overlap in your typical online times, this shouldn’t be an issue. More importantly, your friend’s computer will have to available online or in person for you to restore any data.
Any computer you install CrashPlan on using your own account becomes available to you as a backup destination. Destination computers can be on your local network or on the other side of the country. As with friends, the only requirement is that a destination computer be online when you need to backup or restore. In one scenario, you have a home server with ample free disk space and you use it as a destination for onsite backup. In another scenario, your kid goes off to college and uses a computer that stayed home for offsite backup.
A destination folder can be on your main drive or on an external drive. For example, you can let CrashPlan automatically backup to an external drive as an alternative to something like Mac OS Time Machine.
CrashPlan Central is the name of CrashPlan’s online storage destination. The compelling feature of CrashPlan Central is the pricing. There are essentially two levels. The Individual Unlimited Plan lets you backup an unlimited amount of data from a single computer. The Family Unlimited Plan lets you backup an unlimited amount of data from any number of computers, provided they are all owned by you or by a family member. Both plans compare favorably with all the other online storage options that I considered.
CrashPlan works on Mac OS, Windows, Linux and, uniquely among the solutions I researched, OpenSolaris. The inclusion of OpenSolaris may not seem like a big deal, but that happens to be the OS that we run on the in-house web server that we use for testing. As a result, I’ve learned to appreciate ZFS, the OpenSolaris filesystem. In short, ZFS is one of the most reliable filesystems available, and you can have it for free with OpenSolaris. Put two or more identical hard drives into a mirror or RAID configuration (a snap with ZFS), set up your OpenSolaris box as a CrashPlan backup destination, and you have a very solid onsite backup solution. ZFS can automatically detect and correct physical hard drive errors that would result in silent corruption on most filesystems. With CrashPlan’s automatic archive maintenance running on top of ZFS, you should be protected from everything but physical destruction or theft of your onsite backup.
For now I’m sold on CrashPlan as our main offsite backup solution and seriously considering it for onsite backup too.