Mac Os X Timemachine

[nikster]

I just made a discovery today: TimeMachine on OS X is not just a glorified incremental back-up. It actually is a way to go back in time on your system.

I previously thought that TimeMachine is like any other incremental backup program - it shows you your files at a certain date, and on demand, can restore your entire system to the way it was on a certain date. Plus a glitzy 3D user interface and a hyperbolic name.

Instead, it turns out, TimeMachine will actually show you your system restored to a certain date live and interactively! So if you are in Mail, you go back in time and see exactly how your mailbox(es) looked like that time. You can search, do anything you could normally do. (Except, perhaps, send off mails in the past.) Same for other programs. In Safari, you see your old bookmarks. Etc etc.

Now any normal backup program will do restore points for you and allow you to restore your system. But I have never seen one that allows you to go back and forward between restore points live!

[steffi]

You imply you're able to see your system in the past without clicking restore?

[nidge]

You imply you're able to see your system in the past without clicking restore?

Yes you can see your system, documents, pictures etc without clicking restore. It's all very straightforward.

I am amazed that this thread has been going so long, (3 days), and no Windows user has written what a bad idea it is to be able to see the contents of each individual back up!!! I am sure it will not be long.

[steffi]

You imply you're able to see your system in the past without clicking restore?

Yes you can see your system, documents, pictures etc without clicking restore. It's all very straightforward.

I am amazed that this thread has been going so long, (3 days), and no Windows user has written what a bad idea it is to be able to see the contents of each individual back up!!! I am sure it will not be long.

So what I see is that you can have an application like Mail.app active and it will show itself at that point in time when Time machine is active and you're walking back thru time.

Not all apps seem to do that though. If I have my Safari browser active it selects the Finder before activating Time machine and I can only see the Finder in time machine.

However when you have Mail active you can literally look at the state of your Mailboxes etc at the point in time.

[nikster]

I researched this a bit - turns out only a few apps support TimeMachine, but arguably it's those were it matters the most:

- Mail - as mentioned, you can go back in time through your mailboxes. Very cool. You can restore individual mails that got deleted.

- iPhoto - you can go back in time through iPhoto and restore individual pictures/albums you might have deleted.

- Address book

Not supported:

- Safari - probably because Apple deemed bookmarks not worthy enough? I expect future versions to support it though

- iTunes - only imaginable reason is they ran out of time. Granted, you can browse your Music folder and restore the music from there, but it doesn't make a lot of sense this wouldn't work from within iTunes too.

TimeMachine supports a simple API whereby 3rd party applications can support live browsing and restoration of data from within the application so we can expect that more and more apps will eventually support this.

TimeMachine also has a major caveat: It doesn't store incremental versions of files. On the one hand, that's good because the layout on the backup disk is so simple that you could at any time browse the backups manually without help from TimeMachine and figure out what goes where - it's just plain files on the disk, the format is /backup-date/system name/directory name/.. bla very straightforward. It's clever in that files that have not changed only take up HD space one time even though every backup directory is complete - it's using unix hard links to accomplish that.

The problem is when a large file has a small change - then TimeMachine is storing both versions. Examples that many people are likely to hit are virtual machine disk images like the ones created by VMWare or Parallels, and Entourage email files (one huge file with all emails). Both change every time you use the program, and measure in GB. So it's best to at least exclude the VM files from backup. I would be affected except I use VMWare so rarely I had not noticed this so far

Got most of this info here:

http://arstechnica.com/reviews/os/mac-os-x-10-5.ars/14

[slackula]

I have found TM to be very good, but did encounter one shortcoming. My wife had a MBP fully backed up on our external TM drive and the MBP was stolen. I thought it would be simple to use TM to put the replacement machine to the state that the stolen one was at last back-up, but it wasn't quite so straight forward.

TM recognises machines by their MAC addresses, not host name or machine name so it took a bit of googling and fiddling to get the new MBP and TM to agree to push all the old laptop's info over to the new one. I can see where this would be advantageous, for example in a large office where it is possible that 2 machines shared the same name, but it was a bit of a surprise nevertheless.

[sjaak327]

It is nice in design, but in practice it's utter crap. I had to do a full restore using time machine, but there was one file that was corrupt, hence I coudn't restore the whole thing. And there is no way (at least not that I know of) to skip that file.

So instead of being protected, I had to do a full re-install of Leopard and programs, it's good that I rely on Microsoft Active directory as file server...

Typical mac, it looks nice, it feels nice, but it in practice it's useless

Edited May 20, 2008 by sjaak327

[paveet]

Hmm so that's all time machine is, just storing versions of files on a seperate directory each time. I honeslty thought it'd be something smarter than that... I guess it's another marketing thing that got me thinking that.

So instead of being protected, I had to do a full re-install of Leopard and programs, it's good that I rely on Microsoft Active directory as file server...

Typical mac, it looks nice, it feels nice, but it in practice it's useless

Microsoft Active Directory file server, heh if you want it put it that way. It's a windows server shared folder on a server which is part of an active directory (domain). I quite like the MS server stuff too

[dekka007]

I still combine Time Machine with Superduper and winclone. Superduper allows me to keep a bootable backup to start mac os x then can use timemachine to restore....

Also Winclone is the perfect way to backup your Bootcamp pertition.

[steffi]

If you knew the file you could simply remove it from the filesystem in the time machines backup folder.

It is nice in design, but in practice it's utter crap. I had to do a full restore using time machine, but there was one file that was corrupt, hence I coudn't restore the whole thing. And there is no way (at least not that I know of) to skip that file.

So instead of being protected, I had to do a full re-install of Leopard and programs, it's good that I rely on Microsoft Active directory as file server...

Typical mac, it looks nice, it feels nice, but it in practice it's useless

[steffi]

If it did that you'd need a lot more storage so no it doesn't do that. That would be the way Microsoft would implement it.

Hmm so that's all time machine is, just storing versions of files on a seperate directory each time. I honeslty thought it'd be something smarter than that... I guess it's another marketing thing that got me thinking that.

So instead of being protected, I had to do a full re-install of Leopard and programs, it's good that I rely on Microsoft Active directory as file server...

Typical mac, it looks nice, it feels nice, but it in practice it's useless

Microsoft Active Directory file server, heh if you want it put it that way. It's a windows server shared folder on a server which is part of an active directory (domain). I quite like the MS server stuff too

[nikster]

If you knew the file you could simply remove it from the filesystem in the time machines backup folder.

It is nice in design, but in practice it's utter crap. I had to do a full restore using time machine, but there was one file that was corrupt, hence I coudn't restore the whole thing. And there is no way (at least not that I know of) to skip that file.

So instead of being protected, I had to do a full re-install of Leopard and programs, it's good that I rely on Microsoft Active directory as file server...

Indeed, you could have just deleted the file. Or used disk utility (free with OS X) or disk warrior or Data Rescue on the TM disk to get rid of the corrupt file(s).

In fact, the story sounds a bit weird to me since obviously TM allows you to restore individual files... Everything is useless if you don't know how to use it

Nevertheless, I agree that a backup solution should be able to deal with corrupt files, there should be some sort of error correction built-in. On the other hand, recalling the time when I restored a drive from a Ghost backup, I shudder to think what would happen if one of those archive files had been corrupt. I am willing to bet that it would fail spectacularly. I can't bash Ghost too much since it did save me at that time, but it was heinously slow and had the archive been corrupt I am sure that would have been the end of it.

Now as for why TimeMachine, according to ArsTechnica, Apple did a user survey beforehand. They found that 80% of respondents knew they were supposed to do backups, but only 4% actually did. So the motivation was to get more people to back up - if it's as easy to do as it is with TM, more people certainly will.

[nikster]

Hmm so that's all time machine is, just storing versions of files on a seperate directory each time. I honeslty thought it'd be something smarter than that... I guess it's another marketing thing that got me thinking that.

Huh? Not sure what you mean by that - the ArsTechnica article describes it in detail if you are actually interested. It's pretty clever - they are saving space yet making it so you don't need any special software to be able to browse the backups.

[nikster]

I still combine Time Machine with Superduper and winclone. Superduper allows me to keep a bootable backup to start mac os x then can use timemachine to restore....

Also Winclone is the perfect way to backup your Bootcamp pertition.

It's the only thing I miss from TM - there should be an option to create and maintain a bootable clone. Superduper does it of course, but it's very slow compared to TM.

Probably because TM is the only backup solution out there that uses the journaling information on the disk to figure out what's changed since the last backup.

SD and others are all rsync based so they need to actually compare each individual file with the mirror to find out what's changed, and that takes a pretty long time for approx. 2M files...

[steffi]

Using disk utility (free with OS X) or disk warrior or Data Rescue would be difficult when using a Time Capsule.

[nikster]

Using disk utility (free with OS X) or disk warrior or Data Rescue would be difficult when using a Time Capsule.

I don't know TC - are you saying it's not accessible as a normal hard drive? E.g. I can only access it through TM?

At the very least I am seeing "AirPort Disk Utility for Mac and Windows" under tech specs. Anyway, being unable to access the drive or repair it if needed would seem like a major oversight in a, ahem, backup solution...

Edited May 21, 2008 by nikster

[A_Traveller]

There has been a recent {last month or so I think} upgrade to deal with the 'missing' AirPort functionality, though some have found an associated firmware upgrade led to problems.

Regards

[dekka007]

TC will show as a networked drive so disk utility should not be a problem.

[steffi]

There I think you're refering to the upgrade that allows you to use Time Machine with an USB disk connected to an airport extreme basestation...

That's true.

The current Airport Utility lets you setup the drive for Time Capsule but you cannot repair disk or permissions since the device is only seen thru a network mount.

There has been a recent {last month or so I think} upgrade to deal with the 'missing' AirPort functionality, though some have found an associated firmware upgrade led to problems.

Regards

[A_Traveller]

Without wishing to get into unnecessary oh it's Apple type discussion, I do think that some of the underlying technology decisions within this suite of programs are questionable, and though I applaud anything which simplifies the back-up process from a user standpoint, I'm much less convinced about the techniques. I do anticipate, there will be a re-engineering of this over time to address these latent issues.

Regards

Edited May 21, 2008 by A_Traveller

[sjaak327]

If you knew the file you could simply remove it from the filesystem in the time machines backup folder.

It is nice in design, but in practice it's utter crap. I had to do a full restore using time machine, but there was one file that was corrupt, hence I coudn't restore the whole thing. And there is no way (at least not that I know of) to skip that file.

So instead of being protected, I had to do a full re-install of Leopard and programs, it's good that I rely on Microsoft Active directory as file server...

Indeed, you could have just deleted the file. Or used disk utility (free with OS X) or disk warrior or Data Rescue on the TM disk to get rid of the corrupt file(s).

In fact, the story sounds a bit weird to me since obviously TM allows you to restore individual files... Everything is useless if you don't know how to use it

Nevertheless, I agree that a backup solution should be able to deal with corrupt files, there should be some sort of error correction built-in. On the other hand, recalling the time when I restored a drive from a Ghost backup, I shudder to think what would happen if one of those archive files had been corrupt. I am willing to bet that it would fail spectacularly. I can't bash Ghost too much since it did save me at that time, but it was heinously slow and had the archive been corrupt I am sure that would have been the end of it.

Now as for why TimeMachine, according to ArsTechnica, Apple did a user survey beforehand. They found that 80% of respondents knew they were supposed to do backups, but only 4% actually did. So the motivation was to get more people to back up - if it's as easy to do as it is with TM, more people certainly will.

If it would have told me what file, yes I could have done that, unfortunately it doens't tell you which file it is failing on. That's why it is useless.

Oh I missed your remark about not knowing how to use it. Timemachine isn't ony for individual files, it is a full backup, and it would (in theory) restore your complete harddrive at a date you choose. And I did use it in that way one time successfully, if you don't believe me, do some google, or better yet, startup your Leopard DVD, and look for the time machine restore option that it offers you ....

Edited May 23, 2008 by sjaak327

[nikster]

If it would have told me what file, yes I could have done that, unfortunately it doens't tell you which file it is failing on. That's why it is useless.

Uhmmm... ok? What about disk utility / data rescue etc? Disk utility would definitely have told you which file and/or just fixed the problem.

The beauty of TM is this though: If we assume that your corrupt file could indeed not be recovered by any means, you still have a complete image of all your files in the time-stamped folder. On a bog normal disk, in a normal file system.

You therefore don't _need_ TM to recover your data. You could copy each file manually. Or you could use rsync to do it all for you. rsync will also fail when a file is corrupt, but with the --verbose option it most certainly tells you which file and you could then go on and fix the problem.

It's not convenient, but it's great that you are not limited by the choices you get in one program. Whereas, if a Ghost archive is corrupt, it's good-bye data because the proprietary archive format is readable by Ghost only.

Edited May 25, 2008 by nikster

[sjaak327]

The point is that, even though there was a corrupt file, TM should just restore everything (it was on it's way and failed at 91%) and then I could boot from the hard drive and run Leopard. Now I had to re-installl Leopard and all apps again (when you do a TM restore, your harddrive is of course formatted first.)

Therefore while TM works fine for individual files, it did not work full proof as a system restore option. It did work perfectly the first time, it did fail the second time.

[steffi]

Yesterday it seemed my Air got screwed up so I had to restore from my Time Capsule. This was non trivial at first because if you try to do it wirelessly it will take forever. This was a complete restore from the Install application not a selective file restore. It's not exactly clear how that's done but what you do is boot Leopard install DVD and then select under Utilities "Restore from Time Machine Backup" and follow the steps. Now the trick is that if you do it wireless it will take a very long time so I in my case I wanted to do it over ethernet to the Time Caspule. Well doing that will take up the one USB port the MacBook Air has and you cannot boot into the Installer App via DVD and then remove the Superdrive thinking that it only needs the Time Capsule to do the restore. It seems to need to load more from the DVD during the restore step. So the only way this can be done with a device like Time Capsule is to use Remote Disk which frees up the USB port such that it can be plugged into the ethernet LAN port of the Time Capsule with the USB -> Ethernet adapter.

Doing it this way dramatically improves the restore time.

If anybody knows how this can be done over ethernet when you don't have another computer to use for Remote Disk I'd like to know about it. From what I could tell you always have to have the DVD available during the restore step which because the Superdrive has to be plugged into the MacBook Air's port only will take up all available ports.

The point is that, even though there was a corrupt file, TM should just restore everything (it was on it's way and failed at 91%) and then I could boot from the hard drive and run Leopard. Now I had to re-installl Leopard and all apps again (when you do a TM restore, your harddrive is of course formatted first.)

Therefore while TM works fine for individual files, it did not work full proof as a system restore option. It did work perfectly the first time, it did fail the second time.

Edited May 25, 2008 by steffi

[dekka007]

Easiest way if is the case is probably by a 2 or 4 port USB hub. Not an ideal solution but cheap and will work.

[steffi]

Actually because the Superdrive for the Air only works in the Air's USB port that won't work.

I have an 7 port Hub that I bought in Thailand here.

Easiest way if is the case is probably by a 2 or 4 port USB hub. Not an ideal solution but cheap and will work.

[dekka007]

Ah right...3rd party usb drive..but getting expensive now.

I always use Superduper to keep a

BOOTABLE backup of my Macbook Pro HD on a 2.5" USB Drive saves the heartache....and also use Time Machine on the same drive so have the best of both worlds.

[nikster]

The point is that, even though there was a corrupt file, TM should just restore everything (it was on it's way and failed at 91%) and then I could boot from the hard drive and run Leopard. Now I had to re-installl Leopard and all apps again (when you do a TM restore, your harddrive is of course formatted first.)

Therefore while TM works fine for individual files, it did not work full proof as a system restore option. It did work perfectly the first time, it did fail the second time.

I guess it would be more correct to say that TM doesn't protect you from corrupt files.

I can very well imagine how the decision to make TM abort on corrupt files was made:

"What if the corrupt file is a system file?"

"What if it's a file where you won't know the system is malfunctioning but then later on everything could get hosed"

"Who makes that decision?"

"How can this feature pass QA?"

A huge customer service and QA nightmare and/or class action lawsuits are approaching quickly once you decide to restore a corrupt file. It can't be done. What they could do is provide some sort of CRC error-correction which might or might not work in any given situation. With CRC you would immediately know whether or not it can work. Whereas, if you decide to skip a corrupt file, the system is in an unknown state and anything might happen.

And this being Apple, it would be a safe bet to assume that a class action lawsuit would follow at some later stage.

Edited May 27, 2008 by nikster

[nikster]

Yesterday it seemed my Air got screwed up so I had to restore from my Time Capsule. This was non trivial at first because if you try to do it wirelessly it will take forever. This was a complete restore from the Install application not a selective file restore. It's not exactly clear how that's done but what you do is boot Leopard install DVD and then select under Utilities "Restore from Time Machine Backup" and follow the steps. Now the trick is that if you do it wireless it will take a very long time so I in my case I wanted to do it over ethernet to the Time Caspule. Well doing that will take up the one USB port the MacBook Air has and you cannot boot into the Installer App via DVD and then remove the Superdrive thinking that it only needs the Time Capsule to do the restore. It seems to need to load more from the DVD during the restore step. So the only way this can be done with a device like Time Capsule is to use Remote Disk which frees up the USB port such that it can be plugged into the ethernet LAN port of the Time Capsule with the USB -> Ethernet adapter.

Doing it this way dramatically improves the restore time.

If anybody knows how this can be done over ethernet when you don't have another computer to use for Remote Disk I'd like to know about it. From what I could tell you always have to have the DVD available during the restore step which because the Superdrive has to be plugged into the MacBook Air's port only will take up all available ports.

The Air is truly beautiful but the chopping down of features was a bit over the top there. Why does the superdrive not work on the USB hub, if you don't mind me asking?

Edit: Because it uses more power and higher voltage than any standard USB port can provide, as I have just read on the internet. The alternative would be an external bootable hard disk on the USB hub, or a non-Apple external USB dvn drive which should just run on the hub as well.

I can only hope the next versions of TM are bootable. I mean... all the data is already there, how hard can it be to make a TM drive bootable?

Edited May 27, 2008 by nikster

[dekka007]

You can create a bootable Time Machine drive easily by doing the following:

Re-Format your Time Machine Drive

Open Disk Utility (It's in your Applications/Utilities folder)

Click the Restore Tab

Select your Leopard Install DVD as the Source

Select your freshly-formatted Time Machine drive as the Destination

Click Restore