time machine/partition questions.

[BaBayOOsa]

hey so I was thinking that since i have a 500gb external hard drive and would like to use it as a backup for my internal 160gb hard drive and that I should use time machine. well due to that my machine only has a 160gb internal HD I don't want to dedicate the entire 500gb's to time machine. so I was thinking of partitioning 165gb's for time machine and the rest in another partition to just use for whatever. now my problem is how would I go about doing this? and so that time machine always backs up to the 165gb partition.

also that I could access both partitions easily. but first is this even possible? is it not recommended? and not a good idea?

also if possible could I make two 165gb partitions and one with the remaining 170gb's and use both 165gb partitions as time machine back ups? that way I could back up two computers to one drive on separate partitions and also have 170 for whatever I need it for?

 

[gr8tfly]

A good rule-of-thumb for TM backup space is 2x your source drive (or, at least how much of it you tend to fill). So, in your case that would be 320GB. You could create that size partition, then leave the rest of the 500 available for other things.

If Time Machine doesn't have a partition assigned for backup, as soon as it's mounted, TM will as if you want to use it for backup. Then, select the 320GB partition (or, if nit doesn't ask, just go to System Preferences > Time Machine and select it. Also, if you things that don't need to be backed up, you can use the TM Options so exclude them.

As for partitioning your external drive, use Utilities > Disk Utility. Select your drive (not it's partition), then the Partition tab. Tell it to create 2 partitions, then you can eiher drag the divider to change their size, or type in the desired size. Select Mac OS Extended (journaled) for the format. Click on Options and make sure to select GUID as the partition map.

 

[jimleszczynski]

Somewhat off topic:

Is is possible to alter the partition size of my TM HD? Right now, I have a partition of 1TB. My data size is around 200Gb. I would like to adjust the partition size to 600GB and allocate the 400GB to the other partition. Is this possible without damaging any data on either partition?

 

[Daffodil]

Somewhat off topic:

Is is possible to alter the partition size of my TM HD? Right now, I have a partition of 1TB. My data size is around 200Gb. I would like to adjust the partition size to 600GB and allocate the 400GB to the other partition. Is this possible without damaging any data on either partition?

Sorry, I'm pretty sure partitioning your disk with disk utility erases the data already on it. I imagine you could temporarily move your 200 Gb onto another disk, and then back once you've partitioned you TM one...

 

[jimleszczynski]

Sorry, I'm pretty sure partitioning your disk with disk utility erases the data already on it. I imagine you could temporarily move your 200 Gb onto another disk, and then back once you've partitioned you TM one...

your assumptions are correct. The data remained, however TM didn't recognize the drive as a back-up drive any longer. I ended up zero-ing out the whole drive and starting fresh.

Another question:

Someone on another forum mentioned something about putting the cloned image of your machine on the same drive as TM. Can anyone else explain why they would or wouldn't recommend this?

 

[garycurtis]

Consider what contents you want to backup. By far, the largest chunk on my internal HD is the system. Don't back that up. Only the data. Why would you want a B.U. of the system when you have the original system install CD for emergencies.

In the 'options' feature on Time Machine it asks you to designate folders you wish to EXCLUDE from your backup process. That is were you can achieve some economies.

I have a 1TB in two partitions for my wife's and my own backups. My main hardrive is 120Gb.

 

[Daffodil]

Consider what contents you want to backup. By far, the largest chunk on my internal HD is the system. Don't back that up. Only the data. Why would you want a B.U. of the system when you have the original system install CD for emergencies.

In the 'options' feature on Time Machine it asks you to designate folders you wish to EXCLUDE from your backup process. That is were you can achieve some economies.

I have a 1TB in two partitions for my wife's and my own backups. My main hardrive is 120Gb.

Yeah, that makes sense - if you still have the discs and can reinstall the system just fine, don't waste your space on that. Main counterargument I can think of is that I know some people like to have a bootable backup, in case the hard drive fails, so you're not stuck entirely computer-less if you have no other access to a computer and desperately need something done before getting a new one/taking it in to be fixed.

 

[jimleszczynski]

Yeah, that makes sense - if you still have the discs and can reinstall the system just fine, don't waste your space on that. Main counterargument I can think of is that I know some people like to have a bootable backup, in case the hard drive fails, so you're not stuck entirely computer-less if you have no other access to a computer and desperately need something done before getting a new one/taking it in to be fixed.

That's exactly right.
Not to mention, who wants to deal with the hassle of repairing files by location. My font management is large enough beast to tackle alone. I want the bootable image to be able to pick up exactly where I left off without missing a beat.

I just attempted CCC and it isn't quite what I was hoping for. It backed everything up, but it backed it up into my hd folders instead of creating one bootable disk image file. Perhaps I am setting up the backup wrong?

 

[blevins321]

That's exactly right.
Not to mention, who wants to deal with the hassle of repairing files by location. My font management is large enough beast to tackle alone. I want the bootable image to be able to pick up exactly where I left off without missing a beat.

I just attempted CCC and it isn't quite what I was hoping for. It backed everything up, but it backed it up into my hd folders instead of creating one bootable disk image file. Perhaps I am setting up the backup wrong?

No, it worked right. You can't have a "bootable disk image." It has to be the uncompressed folders in their normal form. Local Time Machine backups do this the same way. Images are created in the case of a Time Machine backup via Time Capsule or another AirDisk simulator (APE, Synology, etc...) but those are not bootable.