Time machine backup on another mac in my network In my network I have:


a Macbook Pro (running Lion)
an iMac (running Lion)


and I want to use the internal drive of the iMac as a Time Machine "target" for my Macbook Pro.

What I did is 


create a sparsebundle on the iMac and mount it
share the mounted volume
connect my MBP to the shared volume on the iMac (with AFP)
tell Time Machine to use that volume to backup


My questions are


is it the best way to achieve what I want to do ?
when backup up, the MBP mount another time machine volume, because apparently it backup on a sparsebundle created in the sparsebundle which is not the simplest solution apparently. I guess this is normal behavior, but is it possible to avoid the intermediate sparsebundle, while at the same time having a control on the backup size in the iMac ?
You can set up your iMac as a fully functioning time machine server by purchasing the OSX Lion Server from the Mac App Store.

This provides you with an official method free from hacks to allow you to backup individual machines such as macbooks etc to a single target machine.  I backup my Macbook Air to my iMac in this way.  For extra safety, I occassionally clone off this backup volume in the iMac to an external disk and store it out of the house.