Server Newbie. TM help

Question

I had a WD ext HDD fire wired to my imac & backed TM directly to there.
I have just set up Mac mini server & thought I would be able to plug in the ext HDD to the mac mini & then wirelessly back up my Imac to the same backup folder created when ti was hard wired through fire wire directly to the imac.
Now that i have removed the ext HDD from my imac & plugged it into the server I can't see it to back up to the same folder as before.
Can anyone help me out with some instructions as to what i need to do?
Thanks,
John

Answer 1

Now that i have removed the ext HDD from my imac & plugged it into the server I can't see it to back up to the same folder as before.
That's at least partly because what you're trying to do won't work.
First off, when using server-based Time Machine backups, Time Machine creates a special file (called a sparse bundle) into which all the backups are stored. This is partly for security purposes but there are other elements to it, too.
In either case, it means than when your client looks to the server, it's looking for the sparsebundle into which it can backup its files. It will not use a plain old backups.backupdb directory (and off-hand I'm not aware of any way to move a plain backups.backupdb directory into a sparsebundle so you can migrate your backups, although it might be possible).
Beyond that, though, in order for your TM to backup to the server you need to designate a specific sharepoint on the server as being a valid TM destination. You can do this via Server Admin - create a sharepoint and select the 'Time Machine backups' options. Then clients on your network will see this sharepoint when setting up TM, and TM will create the respective sparsebundles within it.