Time machine

Hey,

I made a backup with time machine. (its like 127GB).
Next time it back ups will it only put new files in the backup or backup 127GB again?

The first Time Machine backup is always large and will take awhile to accomplish. Subsequent backups should be faster and smaller. It has been my experience that TM will add any changes you have made since your last backup to the new one.

If you're running VM software, keep in mind that a VM can be very large and any change to it will be backed up by TM.

chscag said:

The first Time Machine backup is always large and will take awhile to accomplish. Subsequent backups should be faster and smaller. It has been my experience that TM will add any changes you have made since your last backup to the new one.

If you're running VM software, keep in mind that a VM can be very large and any change to it will be backed up by TM.

Click to expand...

VM = Virtual Machine = stuff like Windows on a Mac?

Thanks for the answer. What happens if my backup disk isn't connect? I read that time machine back ups each hour? I'm not planning to plug in the backup drive all the time ...

If the backup disk isn't connected, it won't back up, obviously But it will automatically back up the next time you plug it in. You can also start a backup at any time by choosing "Back up now" from the Time Machine icon in the menu bar.

and if I delete files of my mac will those same files be removed from the backup?

The deleted files will not be removed from past backups, only from the current backup. And that's a good thing because you can always go backward in time to retrieve files that you may have inadvertently deleted.

Mac Math said:

and if I delete files of my mac will those same files be removed from the backup?

Click to expand...

chscag said:

The deleted files will not be removed from past backups, only from the current backup. And that's a good thing because you can always go backward in time to retrieve files that you may have inadvertently deleted.

Click to expand...

So another way to say that is Time Machine only adds whatever is new to the existing backup. As chscag said, nothing is taken away from your backup even if you delete files on your Mac.
It's really a great piece of Mac OS X.

MYmacROX said:

So another way to say that is Time Machine only adds whatever is new to the existing backup. As chscag said, nothing is taken away from your backup even if you delete files on your Mac.
It's really a great piece of Mac OS X.

Click to expand...

Yeah except my backup drive will be full in no time ...

Mac Math said:

Yeah except my backup drive will be full in no time ...

Click to expand...

Depends on the capacity of your backup drive ;P

I have a 250 GB internal and a 500 GB Time Capsule.
After 3 years, still going strong, the backup disk is nowhere near full, and Time Machine runs every hour.

Disk capacity is cheap so it is a no brainer actually .

Cheers ... McBie

got 500 GB and 1 TB.

My Mac can handle 500 GB

You'll be good with that setup if you don't have any Virtual Machines.
As soon as you launch a VM ( which is usually 1 flat file ), that file changes and becomes a candidate for backup, every time.

Cheers ... McBie

What happens when it fills up is it deletes the oldest stuff and keeps going. In essence, it never technically "fills up". It just makes room for new. But with a 1TB or 500GB backup, you're talking about possibly months or a year of old stuff that would be written over. Probably stuff you already have saved in current backups.

One last note and then a summary of what's been written above:

You can exempt any folder or file from being backed up by Time Machine, and if you do have a Windows virtualization environment on your Mac (ie Parallels, VMWare, VirtualBox), you will want to exempt (as in "not back up") the virtual machine file, as backing it up will cause TM to update far, far longer than it normally would need to, and fill up your backup drive faster.

So to summarize:

After the initial backup, Time Machine only takes a few seconds every hour to update that backup with only things that have changed. It retains things you have thrown away in past backups so you can retrieve them if necessary, and it automatically self-deletes the very oldest backup updates as the drive or volume approaches capacity, so there's no reason for you to worry about it (but having a backup drive that is larger than the capacity of your boot drive is best so that you can reliably store many months worth of changes).