Does Time machine also backup the parallels win partition?

I'm assuming you mean VM (virtual machine) and not "partition. "Parallels 7 will not work with Mavericks. You need P8 or P9. But yes TM will back up all Windows running under Parallels. The Parallels folder is in your documents. In this folder is the Windows version you installed with all your programs and files.

Virtualization software creates a large virtual-disk container that is constantly changing, so it has to be backed up every time Time Machine runs. That will quickly fill up any backup destination.

You should exclude the virtual-disk file(s) from your Time Machine backups. To do that, click the Options button in the Time Machine preference pane. Back up the files on the virtual disk from within the guest system, using a native backup application.

A compromise solution is to create a "snapshot" of the virtual machine in the virtualization software (not a Time Machine snapshot.) That will give you a single large file that never changes and only has to be backed up once. All the subsequent changes will be stored in a new file that's initially much smaller, but will grow over time. You should still exclude that file from TM backup. If you ever need to restore the VM from Time Machine, you'll have a working setup, which will make it easy for you to restore the rest of the data from within the guest system.

Thanks Linc - I am planning to install MS Windows 7 in Parallels and would appreciate some clarifications regarding backups please.

Linc Davis wrote:

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A compromise solution is to create a "snapshot" of the virtual machine in the virtualization software (not a Time Machine snapshot.) That will give you a single large file that never changes and only has to be backed up once.

Is this snapshot stored in the virtual environment or outside it? If outside the VM then should I allow TM to back it up?

All the subsequent changes will be stored in a new file that's initially much smaller, but will grow over time. You should still exclude that file from TM backup. If you ever need to restore the VM from Time Machine, you'll have a working setup, which will make it easy for you to restore the rest of the data from within the guest system.

This expanding file is presumably the VM

Thanks for your advice

Time Machine will backup all data on your boot volume (minus items in the Trash, and some hidden temporary items like caches). This means that any Parallels installation you have saved to your main boot volume will be backed up by Time Machine.

However, some VM solutions like Parallels come with a special setting to prevent them from being included in Time Machine backups, so be sure to check this setting's status:

Beyond this, if you have set up Parallels or another VM to load and run the Windows installation you already set up on a Boot Camp partition, then this partition will not be backed up by Time Machine; however, in all other cases the virtual machine installation should be on a local volume that can be backed up by Time Machine (the default location for them is usually in your Documents folder).

If you have not saved your VMs in the default Documents folder, then the only other concern is if they are on another partition, such as a secondary hard drive you have attached to your Mac. This will not be backed up by default, but you can ensure it is by removing the drive from the Time Machine exclusion list in the Time Machine system preferences (click the Options button to get to this list).