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britt0289

macrumors newbie
Original poster
Jan 12, 2013
13
0
Hello all,

I am running ML (after upgrading from SL). I am trying to back up the bootup drive so I can repair the disk by a clean install. I have a 1TB that I initially used for my movies, music etc...but since this issue arose, I purchased a 500GB to use as a backup. I formatted it to Mac Journaled and had TM have a spin with it. It said the total back up should be 126GBs. Cool. It estimated that'll take about 4 hours to do. cool. I take a nap wake up and see its completed. It says that 403 out of 500 GBs is available.

Huh?

How is this possible? Is it not enough space? It didn't shoot me any error messages when I checked. I tell it to back up and it only does small portions but the space stays the same. Am I missing something?? I need this done like yesterday :-(
 

britt0289

macrumors newbie
Original poster
Jan 12, 2013
13
0
Launch the time machine app with the back up disk plugged in. Is there more than one backup?

It is.
And no, there is no back up on this drive. I had a drive fail on me that was my old back up but its trashed so yeah. Now it says 402 of 500 available so...I don't get this. It never done this before on SL.
 

Weaselboy

Moderator
Staff member
Jan 23, 2005
34,073
15,497
California
It is.
And no, there is no back up on this drive. I had a drive fail on me that was my old back up but its trashed so yeah. Now it says 402 of 500 available so...I don't get this. It never done this before on SL.

So I understand... you are saying the TM backup is only using about 98GB of space on the backup drive? How much disk space is shown in use on the Mac if you click the Apple at the top left then, about this mac/more info/storage?

There are some swap and cache files that TM does not backup, so that would account for some of the difference.
 

gnasher729

Suspended
Nov 25, 2005
17,980
5,565
It is.
And no, there is no back up on this drive. I had a drive fail on me that was my old back up but its trashed so yeah. Now it says 402 of 500 available so...I don't get this. It never done this before on SL.

Certain files will not be backed up. You can yourself choose folders that will not be backed up. Applications can tell Time Machine to not backup things like cached files, or files that are created by an app while it does its work that can be thrown away without any loss. I haven't tested it, but your Trash folder may not get backed up, so if you have 30 GB in your Trash without emptying it, that would explain the difference.
 

britt0289

macrumors newbie
Original poster
Jan 12, 2013
13
0
So I understand... you are saying the TM backup is only using about 98GB of space on the backup drive? How much disk space is shown in use on the Mac if you click the Apple at the top left then, about this mac/more info/storage?

There are some swap and cache files that TM does not backup, so that would account for some of the difference.

Yes! It said the backup would be about 126GBs but it only did 97GBs. And the storage says 89.18 out of 249GBs free.

Certain files will not be backed up. You can yourself choose folders that will not be backed up. Applications can tell Time Machine to not backup things like cached files, or files that are created by an app while it does its work that can be thrown away without any loss. I haven't tested it, but your Trash folder may not get backed up, so if you have 30 GB in your Trash without emptying it, that would explain the difference.

My trash can has been deleted. And how would I do this? TM has such a basic set up :-/
 

ZMacintosh

macrumors 65816
Nov 13, 2008
1,445
684
Time machine does not back-up files in the trash nor does it back up alot of system files. you can add those to the inclusion list of time machine in time machine preferences.

I would erase the disk using disk utility and when it becomes available again and OS X prompts you to use it as back-up disk Say yes and let it back-up and see if its any different. if not then theres a large system file that isnt being backed up
 

Weaselboy

Moderator
Staff member
Jan 23, 2005
34,073
15,497
California
Yes! It said the backup would be about 126GBs but it only did 97GBs. And the storage says 89.18 out of 249GBs free.

That does sounds like a bid difference to just be cache and swap files not backed up. You might try using OmniDisksweeper to look at your drive and see if anything big jumps out at you that does not normally belong there.

Have you done anything to the system at all lately that may have caused extra swap files?
 
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