backuphard drivepartitiontime-machine
Is it possible to partition and external drive an use only one of the partitions for a Time Machine backup? Or does Time Machine need its dedicated hard drive? (I've never used Time Machine before.)
If it is possible to do this, do I need to pay attention to anything in particular to make sure it'll work without issues?
I am aiming for one Time Machine partition and one NTFS one on the same external hard drive. Is this feasible?
Your preferred setup is not possible: OS X can't share an NTFS disk with Windows for backup because Time Machine needs HFS+ (from http://support.apple.com/kb/HT1427):
Manually preparing a new disk for Time Machine
(...)
If you want to partition the disk, click the Partition tab and select a layout. Make sure "Mac OS Extended (Journaled)" is selected in the Format menu for the partition that will be used for backups. Click Apply.
Luckily, you don't need two separate drives. Using partitioning you can trick your computer into thinking it is connected to more than one drive, although there's only one. In this case, two partitions will suffice, one HFS+ and one NTFS.
(Why only one NTFS partition although you back up 3 Windows computers? Because Windows stores backups in folders named after the computer name so there are no conflicts whatsoever (see this post). You can use one NTFS partition to store backups of multiple Windows computers.)
I'd recommend that you create the HFS+ partition on your Mac first, then, on your Windows computer, format the other partition to NTFS:
When you're done, plug the drive again into every Mac/Windows computer and select the corresponding partition as backup drive (see here for OS X and here for Windows).
To prevent the NTFS partition from being mounted every time you connect the drive into your Mac add this entry to /etc/fstab (as explained here):
LABEL=BACKUP_WINDOWS none fusefs_txantfs noauto
Replace BACKUP_WINDOWS with the NTFS partition name.
This setup works like a charm.
I have a very similar configuration:
My external 1 TB drive, which I use for backing up my Mac and my wife's Windows PC, has two partitions called "Time Machine" and "BACKUP_WINDOWS":
The problem is that Time Machine is designed for HFS+ formatted volumes.
You might have luck with the Paragon NTFS driver but if the NTFS volume is case-sensitive and your normal mac partition is not, you will have problems backing both up to the same Time Machine volume.
You might be able to use Carbon Copy Cloner to copy the contents of the NTFS volume to an image file but not a bootable one.
Also check out this blog which talks about related NTFS issues.
Best Answer
Time machine doesn't care what else is on the destination drive as long as the volume (partition) you choose meets the minimum requirements. If the volume you select isn't formatted properly, Time Machine will offer to erase and reformat the part of the drive that will contain your backups.
You might want to try resizing partitions using whatever tool you want before you start accumulating a lot of Time Machine data in case you want to be able to adjust the size of the partitions down the road, but that's more of a problem with partitioning and not something that Time Machine causes.