Using external storage with Time Machine (Our CrabApple of the Week)
Posted by JohnnyAppleseed | Under Crabapple, Hardware, Programming, Review, Software Friday Apr 25, 2008EDITOR’S NOTE: First, an administrative note: We’ve been having some real issues with Wordpress version 2.5, and a lot of effort has been focused on fixing them this week. Until we have those worked out, our frequency of publication might be a bit lower than we’d prefer. Enough said about that, now on to today’s tip…
photo credit: mac_vegetarianWhen Leopard (Mac OS X 10.5) first came out, one of the greatest new features - and, unfortunately, one of the most frustrating for some users - was Time Machine. Time Machine is probably one of the best pieces of backup software ever written, in that it makes it absurdly easy to retrieve previous versions of accidentally (or purposely) erased or damaged files. But the only problem is that for many users, it has only consistently worked well if you were willing to dedicate a hard drive (or at least a partition) to Time Machine.
Some users have other storage sitting out on their local networks (known as Network-Attached Storage, or NAS), and wondered why they couldn’t use that for their time machine backups. The funny part is that shortly after Time Machine first appeared, a company called Xiotios Software came out with a small program called iTimeMachine which had only one purpose - it enabled the use of AirDisks and Network Disks in Time Machine.
And it worked, until Apple came out with an incremental upgrade to Leopard, which promptly broke the ability to use external disks for backups for many users. Another upgrade, and some users have reported that they can use external drives, while other still cannot.
We think that what iTimeMachine does is the equivalent of opening a terminal window and entering this:
defaults write com.apple.systempreferences TMShowUnsupportedNetworkVolumes 1
… which is another method that some folks have used to allow Time Machine to access networked drives. But this alone doesn’t seem to be sufficient in some cases. Today, Mac OS X Hints published an article describing a three-step process to create a Time Machine backup on a network-attached storage (NAS) unit. 
photo credit: Kai HendryUnfortunately, it comes a bit too late for us - earlier this week we bit the bullet and dedicated an external drive to Time Machine, rather than making further attempts to save Time Machine backups to a drive connected to our “Unslung” Linksys NSLU2, which would probably have worked had we had the above information available.
Our “Crabapple of the Week” gets tossed at Apple, for not making Time Machine work well with network-attached storage, or even their own AirDisks, in the first place, and for not yet fully supporting them even as I write this. Of course, those hard cider drinkin’ boys will have already run down to the Apple store to buy a Time Capsule, but for those of us not ready to open our wallets every time Apple comes out with some new (and, dare we say, sometimes overpriced) gadget, information on how to make Time Machine use our existing devices is much appreciated. And another Crabapple goes to Apple for giving out questionable information (this is a quote from Wikipedia’s page on Time Machine):
….. According to Apple, it can only be backed up to network drives if they are being hosted by another computer running Leopard (including Leopard Server). Further, the volume needs to be formatted with the HFS Plus file system, with journaling enabled. External hard drives typically are pre-formatted with the FAT32 filesystem. To use Time Machine, the hard drive must first be formatted, which erases all data. The hard drive will not require formatting if it is already using the HFS filesystem.
Except that for a period of time after Leopard was released, we were making successful Time Machine backups to a drive attached to the aforementioned Linksys NSLU2, which runs a version of Linux, not Leopard. Oh, and the drives were formatted using EXT3 (the format used by the NSLU2) and we did not reformat them, and Time Machine did not erase any data on the drive. So, if the above information from Apple (as reported in Wikipedia) is true now (and we do not believe that the above is entirely true), it’s because Apple changed something during a recent Leopard upgrade. Would Apple deliberately try to make users think they have to purchase a Time Capsule, or at least use a dedicated external drive, even if that’s not strictly true? We won’t speculate further on Apple’s possible motives for spreading questionable information, but we do wish they would just go ahead and fix Time Machine to play nicely with whatever external storage the user may have available.
Subscribe to CAF
