Mac has a great backup solution called Time Machine. Typically you must use like storage products but you can also use your ClearOS server to perform these backups.
The prerequisites are simple. You will need to either set up a Flexshare or have the user backup their Mac to their home directory. Simply make a connection to the share and you are ready to go. (ie cifs:servername/username)
This method has been tested on Snow Leopard. Please send us some feedback if you get it working on other version. I've been told that Lion only takes AFP for its Time Machine. If this is the case then we will have to write a different howto on that.
The bulk of what needs to be done is on the Mac itself. First, open a Terminal from the Utilities Folder under applications. Run the following command to tell your mac to allow other mounted volumes as acceptable Time Machine storage devices:
defaults write com.apple.systempreferences TMShowUnsupportedNetworkVolumes 1
Next, you will need to create the sparebundle file required to back up your mac. Normally the Time Machine does this automatically but you will get permission errors if you try to use the share at this point.
You will need 2 bits of information. First you will need your machine name and second, you will need your MAC (media access control) address of your network card.
ifconfig en0|grep ether
Open up the Disk Utility program <navigation>Applications > Utilities > Disk Utility</navigation>. Select 'New Image' and change the save location to save it to your desktop.
Work your way from the bottom options up:
The file will be appended with .sparsebundle. In my case it was called DLMacPro_001ff352eba1.sparsebundle
Copy this file to the location of your choice on the ClearOS server. I copied mine to me home directory. After you have copied the file, delete it from your desktop.
I started out by opening my 'Options…' settings in 'Time Machine' to exclude nearly all my directories at first so that I can effectively test it. Under 'Select Disk…' I selected my home directory where I have copied my sparsebundle file.