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cold aspiration · May 10, 2008, 09:44 PM

Hey everyone.

So I have been using time machine for about 5 months now and it has been great! Saved my ass a couple of times already. I got the alert that my 160 gig external was getting full quite some time ago and knew that time machine would start deleting some of the older backups to make space for the new ones. After 5 months of flawless performance, now time machine keeps failing at backups. It says that the backup file is too big for my external. The message says something along the lines of, "the backup file is 900mbs but you only have 1.7gigs fee." ..... ??? Shouldn't 900 mg fit into almost 2 gigs? Also, if three wasn't free space, shouldn't time machine be deleting some old backups?

The funny thing is, I got this message at 1230 and looking at time machine, my last succesful backup was at 1105. I didnt do anything at the computer in that hour between the last successful backup and the one that failed at noon.

Anyone have any suggestions? Ideas?
Thanks in advance

dampeoples · May 11, 2008, 01:52 PM

The TM pads the file, you can see how much by looking at the system log in Console.

cold aspiration · May 11, 2008, 04:35 PM

Originally Posted by dampeoples

The TM pads the file, you can see how much by looking at the system log in Console.

Hmm, what does that mean? And what does that matter, how can I fix it.?

Cold Warrior · May 11, 2008, 04:42 PM

It means TM is adding a bit of additional space used onto what it says it uses, so that TM thinks it has less space than what's technically available on your HD. You can't fix it, AFAIK.

You'll need to delete a lot more or get a larger external.

cold aspiration · May 12, 2008, 12:35 AM

alright, so I get that part now. But why all of sudden? My hard drive that I am backing up is partitioned so the actual "Macintosh HD" is 80gb. I guess I'm just confused as to why TM decided now that it doesn't want to delete old backups to make space for a newer one and now just stops what its doing?

TM really added on another 80gb or so of padding? Not so convenient when the external needs to be more than 100% larger than the target drive

Cold Warrior · May 12, 2008, 12:42 AM

You said you have 2 GB free for 900 MB of data. I'm confused about your reference to 80 GB of padding.

cold aspiration · May 12, 2008, 03:20 AM

Sorry for the confusion, I was referring to that my external is 160gb and my target HD for backup is 80gb. And that TM is suppose to delete old backups if it runs out of space in order to have more updated copies?

cold aspiration · May 12, 2008, 06:51 AM

Update:

Weird, after coming back to my external and plugging it in. TM ran and updated normally except instead of the usual 100 to 500 mb of update it did 15 gb and now its working fine. Wonder what happened?

I did go to my wireless network and backed up to a time capsule before returning and plugging it into my external.

Hal Itosis · May 13, 2008, 03:14 AM

Originally Posted by cold aspiration

alright, so I get that part now. But why all of sudden? My hard drive that I am backing up is partitioned so the actual "Macintosh HD" is 80gb. I guess I'm just confused as to why TM decided now that it doesn't want to delete old backups to make space for a newer one and now just stops what its doing?

TM really added on another 80gb or so of padding? Not so convenient when the external needs to be more than 100% larger than the target drive

Originally Posted by cold aspiration

Sorry for the confusion, I was referring to that my external is 160gb and my target HD for backup is 80gb. And that TM is suppose to delete old backups if it runs out of space in order to have more updated copies?

You may also want to start referring to the source disk as the "source"... instead of target.

ph0ust · May 13, 2008, 01:46 PM

i am getting these same errors all of a sudden. i have a 250GB external hdd. time machine was working fine. it filled up eventually, considering it is backing up a ton of information. it asked me if it was fine to delete old backups to replace them with new backups. i said 'ok'.

now all of a sudden i continuously (as in every damn hour) get errors saying:
**********************
Time Machine Error
This backup is too large for the backup volume. The backup requires 51.5gb but only 44.8gb are available.

To select a larger volume, or make the backup smaller by excluding files, open System Preferences and choose Time Machine.
**********************

so what the heck is that?

ph0ust · May 13, 2008, 02:00 PM

after looking at this some more... it seems that there is only a single backup on my external hdd and it is over a week old (5/9/08). it doesn't even look like time machine is making any differential backups at all and it thinks there isn't any space. did it somehow loose track of all the previous backups? any idea what the heck is wrong with time machine?

ph0ust · May 15, 2008, 04:52 PM

bump.... anyone have an idea what time machine is doing in my situation? my external hdd has 24gb of non-backup related data on it (just other stuff) and two backups. the message i get says it needs 51.5gb of space for the backup, which it should have since this is a 250gb hdd. moreover, though, is that it seems to be doing full backups instead of differential backups. i always assumed that time machine doesn't backup 100% of the hdd every time it does a backup. any ideas?