View Full Version : Time Machine.. Tiger?
01-25-2008, 07:32 PM
So, todays episode was a little weird to me with the Time Machine reviews. I personally haven't had a problem with the feature and actively use it, so I'm not quite sure what other people are doing to cause your system to lock up every time it tries to back up.. but anyway, on to the real reason why I'm making this thread, a few times during the segment Time Machine was referenced for Tiger and is said to have worked better in Tiger than Leopard. Was there something I missed in Tiger, or did this feature go by a different name on that OS?
01-26-2008, 01:52 PM
This has totally confused me as well, and I thought Patrick knew his stuff!
I'm wondering if the readers letter was about something like mozy and had a brain fart whilst writing it.
01-26-2008, 02:48 PM
I was really puzzled about that too. As already said, Patrick should know that Time Machine is a feature of Leopard.
After watching that particular portion of the show, I quickly paused my appleTV and Google'd around to see how I can get Time Machine on my mac running Tiger. As far as I had known, Time Machine was only a Leopard feature. About three or four results into the Google search, I came across this thread and realized that Patrick was mistaken, and is not the mac user he claims to be :[
01-26-2008, 07:25 PM
Funny. I did exactly the same thing...saw the Time Machine story and heard people talking about Tiger...googled Time Machine and Tiger...found this link....came here to read more confusion.
If anyone knows if this is possible, I'd love to get my work machines on the bandwagon.
01-27-2008, 05:12 AM
wow, glad to know I'm not completely alone in my total confusion. I'm pretty much prone to blind trust when it comes to Patrick, so I guess it's good that I stopped by here :)
01-28-2008, 01:46 AM
Patrick? hello... Patrick. Time Machine is a Leopard ONLY feature. There are changes to the underpinnings of the OS to make it possible to run Time Machine, so anyone saying they're running it in Tiger is either wrong, or... wrong. They might be talking about some other backup solution, but that means they're wrong.
From my experience, the wording you quoted in the podcast suggests they were using some backup solution in Tiger and it didn't keep working well in Leopard after the upgrade. That would include most of the backup solutions out there. Like I said, Apple made some changes to the underpinnings of the OS to make Time Machine work. Be glad it only seems to have affected backup software.
AND Contrary to popular belief, backups are not simply a matter of having a copy of files.
Modern OSes include metadata, permissions, and other data with each file, and that data can be very valuable. Imagine searching for all the documents you wrote between Jan 10 and Jan 12. Now image recovering from a backup and all those files showing up as if they were created the day you restored from backup. Or maybe you're using the built in webserver and have special permission on files that web visitors see, but after a restore all the permissions are back to default permissions.
The issue goes much much deeper. The unix foundation of OS X allows for Symbolic and Hard links. In addition, OS X itself uses inode numbers on each file so users can do advanced things like move a file from their desktop to their movies folder while it's still downloading or copying. They also use the inode for aliases, like a shortcut in Windows, except that you can move the original file and the Alias will still open the right file. If that inode number is not restored during a recovery from backup, then aliases will default to the last known location of the file and update the inode number. That means that most Aliases will still work, but Aliases will be broken if their original file has moved w/o the alias being used to access it since the move.
There are other even more technical features in unix that developers can and do use in unix, and if files are not restored properly, then programs may not work after a recovery from backup. Fortunately most programs on the Mac either don't use these features, or they include reasonable recovery steps, like automatically creating a new copy of a missing preference file.
Clearly the most important thing to backup is the content of your files, and there are several backup solutions on the Mac that only do that. They don't go the extra mile to capture and restore all the Metadata and other features (Retrospect and CCC don't). Currently SuperDuper does the best job of it, but the last I knew they claimed that there is no published way to capture and then restore inode numbers, which no one else captures/restores either.
NOTE: SuperDuper hasn't released a Leopard compatible version yet. They're within one week if beta tests finish well.
SuperDuper has described their Leopard version as living on the same disk and even the same partition as Time Machine, and that's no easy task. It's unclear to me if they are going to hardlink to the same files as Time Machine, allowing for a very fast and super space efficient backup.
The biggest reason to use SuperDuper when Time Machine already backs up every, is that a SuperDuper backup can be booted from. That's right, if your internal drive fails, you hold the option button during boot up and choose your SuperDuper drive to boot from it. You can use your Mac just like normal until your replacement drive is installed, then you just tell SuperDuper to restore from your Time Machine drive to your new internal drive, reboot holding option, and you're completely back to normal.
I could go on and on about SuperDuper and backups in general, but the point is that Time Machine is almost perfect and Super Duper fills the only big gap.
P.S. backup has been a pet peeve since... my first permanent BSOD.
01-29-2008, 07:01 PM
Patrick isn't alone is this slip. Steve Jobs made this slip during the Keynote speech not that long ago. He has said that he hasn't made the jump to Leopard and so he doesn't use Time Machine. So yes he should know but if the big man makes the mistake, I'll let Patrick get away with it too.
Also, when I'm using TM I only back up my home directory with it. I can install the system just as easy so there is no reason to back of ALL of my machine. The feature I wish they would add is multiple backup locations.
As a rule of thumb I keep 2 backups.