Will TimeMachine back up one external HD to another?

[hank-b]

I have a G4 iMac with a smallish HD (80GB) and two external firewire drives, one 500GB (Freecom) and one 750GB (WD MyBook). I'm running 10.4 (this machine doesn't support 10.5).

If I get a new, shiny, iMac with 10.5 and TimeMachine then will I be able to designate the 750GB as my TimeMachine drive and have the Mac back up both the internal drive and the 500GB drive onto this, or will TimeMachine only back up the internal drive?

Why do I need to know this? Well, if TimeMachine only backs up internal drives, then I'll need to get an iMac with a larger internal drive than I would if TimeMachine can back up one external drive onto another.

HB

 

[SilentPanda]

I believe Time Machine will only back up your system partition. On my Mac Pro I have 2 500GB and 1 250GB drive and I think time machine only backs up the 1st 500GB drive (to the 2nd one). I wish it would work on non-system drives. Although maybe it does and I'm not aware.

Edit: I did just find this (I haven't read it) which seems to say that it can...

http://www.onedigitallife.com/2007/10/30/does-time-machine-backup-external-drives/

 

[LouisBlack]

I believe Time Machine will only back up your system partition. On my Mac Pro I have 2 500GB and 1 250GB drive and I think time machine only backs up the 1st 500GB drive (to the 2nd one). I wish it would work on non-system drives. Although maybe it does and I'm not aware.

Edit: I did just find this (I haven't read it) which seems to say that it can...

http://www.onedigitallife.com/2007/10/30/does-time-machine-backup-external-drives/

I don't think this is the case. I have my main drive partitioned so I have an 80GB System drive and a large drive for home directories (I had some problems with Leopard and it's just easier this way). Time Machine backs up both partitions.

When you go into the back up folder on the TM drive, it has 'Louis' iMac' and then within that folder it has both 'System' and 'Home' folders.

All you need to do is take the external drives out of the ignore list in TM prefs.

 

[Eidorian]

By default Time Machine has other external drives not set to be backed up. You can remove them from the list though to have them backed up.

 

[hank-b]

Thank you all - sounds like it should be possible then.

 

[ChrisA]

I have a G4 iMac with a smallish HD (80GB) and two external firewire drives, one 500GB (Freecom) and one 750GB (WD MyBook). I'm running 10.4 (this machine doesn't support 10.5).

If I get a new, shiny, iMac with 10.5 and TimeMachine then will I be able to designate the 750GB as my TimeMachine drive and have the Mac back up both the internal drive and the 500GB drive onto this

I have this exact setup and yes it works.

Be default Time Machine backs up all drives that are visable on the desktop except for the Time Machine dive. You'd have to go in and exclude folders to prevent the default.

Note that the Time Machine drive really needs to be larger, much larger, maybe double the size of all the data you have on all of your drives. I see this as a major fault with TM. What happens if you have a LOT of data? THere should be an easy way to use multiple TM drives. Yes I know I could set up a RAID and use that as a TM drive but I meant "easy" as in something the average Mac user could do.

 

[SilentPanda]

Note that the Time Machine drive really needs to be larger, much larger, maybe double the size of all the data you have on all of your drives. I see this as a major fault with TM. What happens if you have a LOT of data?

Unless you are constantly running your hard drive at 100% capacity there's no reason to have a hard drive that is larger than your backed up drives. If you just have 10% of your hard drive free on your main drive that leaves Time Machine with 10% of fudge room for you to go back. I guess it really just depends on how far back you want to go.

 

[Le Big Mac]

I too am backing up one external to another using Time Machine. You do have to select it, though.

 

[kcoolrule]

Can't back-up Ext HD to another; Greyed out!

Hey everyone,

I read the responses to the this thread and I followed the steps but I didn't have success like everyone else. I have a WD 150 GB I want to back up to my 1 Terabyte WD HD that is acting currently as Timemachine. I bring up that drop list of Excluded devices but my 150 GB HD is greyed out. Why is that? Is it because of its native windows formatting? I can read all the files on MAC OSX just fine though.

I'm worried the drive is going bad because it doesn't autoplay all the time when first plugged in. In windows it displays computer jargin when you right click it. It may take a 2nd time to get autoplay running.

Will copy and pasting all the internal files from the 150 gb over the other be my only option here?

Thanks