Time machine unnecessarily doing an entire backup

[karohan]

So I had an entire Time Machine backup. My HDD failed, so when I got my new one, I restored from my backup. Now I want to update the backup, but it's backup up the entire drive, which seems superfluous. Is it supposed to do this?

 

[Jagardn]

So I had an entire Time Machine backup. My HDD failed, so when I got my new one, I restored from my backup. Now I want to update the backup, but it's backup up the entire drive, which seems superfluous. Is it supposed to do this?

I just replaced my wife's HDD and when it came back up, it started doing something similar. It's actually doing a full compare, but you'll see that the amount of data backed up will be minimal. Once it's done checking the disk, it won't take long.

 

[maflynn]

So I had an entire Time Machine backup. My HDD failed, so when I got my new one, I restored from my backup. Now I want to update the backup, but it's backup up the entire drive, which seems superfluous. Is it supposed to do this?

Because to TM's backup software it thinks that everything changed. In a sense it has all changed, the drive changed and I think TM recognizes this and so it goes to back everything up.

 

[karohan]

Hmm, okay I think you were right Jagardn. It looked like it was doing the full backup for about 25gb (out of the couple hundred), but then at some point it just said indexing backup, so I'm assuming it was finding the same files in my old backup. It finished pretty quickly from there.

Thanks for the replies

 

[Jagardn]

Hmm, okay I think you were right Jagardn. It looked like it was doing the full backup for about 25gb (out of the couple hundred), but then at some point it just said indexing backup, so I'm assuming it was finding the same files in my old backup. It finished pretty quickly from there.

Thanks for the replies

Yup, the same way it happened for me. 🙂