Time Machine Deleting Past Backups.

[adamlbiscuit]

I don't know if its supposed to do this or not because i am a new time machine user so i am a newb at it.

I have a HFS+ Backup Drive using the GUID partition table that is used by time machine. Yesterday I had quite a few backups in my backup directory, today i come on to find that some of these backups are missing. Not all, but some.

Is this normal behaviour? Does it delete some backups?

 

[miles01110]

It deletes older backups as TM requires more space.

 

[adamlbiscuit]

ah i see. I have plenty of space on my HD though (sorry i forgot to mention) think about 500GB.

I've been researching and i'm confused about all this Daily backup thing that people have been talking about. I gather it does backups every hour, and then at the end of the day deletes them and keeps the latest to use as the daily backup. And the same goes for the whole week, then it deletes all your daily backups but keeps the latest to use as the weekly backup.

However if thats the case then why has it deleted my backup for yesterday? (grandted it wasn't strictly speaking yesterday it was 10 past twelve in the morning) I think it might have been thrown off because of the clocks going forwards where I am.