NooB Question about Time Machine

[BasilFawlty]

I had set up my Time Machine to use Time Capsule for backups for both mine and my wife's iMacs (and my Macbook), Well, it was only a 500GB TC, and eventually we started running out of space, so I decided to change my iMac to use an external 2TB drive I have for backups instead of TC. When I was using teh TC for backups, it was making one bog file with an extension (my name).sparsebundle). But when I changed over and started using the TB external, it doesn't have a .sparsebundle file. Instead, it has a folder called something like bacckups.backupdb with a separate folder for each backup set.

My NooB question is, why was it putting a ".sparsebundle" file when I was using TC as my backup drive, but now it's using just regular files? What's the difference and is one better than the other? Just curious.

 

[mannyo1221]

They both serve the same purpose, and make no difference to the actual usage and functioning of time machine. When you backup to a network resource time machine uses a sparsebundle, and when using USB it uses the standard HFS filesystem.

If you mount a sparsebundle file on your mac, you'll see it contains the same folder and file structure as the USB HD.

 

[deep diver]

I don't know about TC. The "bacckups.backupdb" folder is just what TM uses. If you enter that folder you will see what appears to be a normal directory/file structure of your machine. You can use TM to get back an old file or go into that folder from Finder (but you may not want to do it that way. It might mess up TM if you goof something.) I only use TM on an external drive. I don't see any reason to use anything else.

 

[BasilFawlty]

They both serve the same purpose, and make no difference to the actual usage and functioning of time machine. When you backup to a network resource time machine uses a sparsebundle, and when using USB it uses the standard HFS filesystem.

If you mount a sparsebundle file on your mac, you'll see it contains the same folder and file structure as the USB HD.

Ok, well, that explains it. Thanks! (This whole concept of "mounting" is foreign to this life long PC user, but I think I understand.

 

[blevins321]

Network drives have different file system permissions than regular attached drives. Think of the sparsebundle as OSX making a "file system in a box" that can have the elaborate dating and permissions mechanism that time machine requires. And the purpose of a "bundle", which is just a folder of set-sized file blocks, is to reduce overall network overhead and get around any file system size limits the NAS might impose.