time machine backups

[chinhiphone]

i have a question about time machine backups...

i dont need to backup my files often and the drive i am using for a time machine backup is also my backup drive for other computers. currently when i backup it creates a folder on the drive as a backup. i only need to do a backup about once a month or when i feel i made a major change in my computer.


my question is how is each backup on the hdd different from one another? do they depend on each other? since i only need to do a backup once a month, i would like to backup, then delete the old backup, only keeping one backup at a time on the drive to save space.

is this possible? i did a 2nd backup for the hell of it and the 2nd backup seem to go a lot faster than the first. why is that? so is all time machine doing is juss backing up the chances in the 2nd backup and the 1st backup is still needed? or was it only faster becuz time machine scanned the drive and saw most was unchanged and both backups are independant of each other?
thanks

 

[Jolly Giant]

you might be better off skipping TM altogether and use e.g. Carbon Copy Cloner instead. the app lets you schedule incremental backups (to a full clone done the 1st time you used it). for instance, you could set it so that the backup is done when the backup drive is connected.

TM really works best when it can do regular (hourly, every 4 hours, etc.) backups - it may act up if used once a week only.

TM will do a complete backup initially (takes a long time if you have a lot of data), with smaller, incremental backups on subsequent runs.

you might find this FAQ useful.