Limiting the Time Machine's Time Capsule space

Hi.

The best Time Machine info outside Apple can be found here.

You cannot partition the Time Capsule's internal drive, but in Mountain Lion you should be able to limit the size of the sparsebundle containing your backups, and it is also possible to create a disk image on the Time Capsule's drive.

Pondini advises TM needs 2 to 3 times the size of the data to be backed up (2GB is definitely too small). But I have found that 1.5 times is enough for more than a year's worth of backup data. However, my strategy is to also maintain an Archive drive to which I move inactive files (like finished projects), and I keep a clone of that Archive drive separately from TM.

Thus, I use TM solely for the ability to restore my startup drive (some or all) if necessary, and "historical archives" are maintained separetly. I have a 500GB Time Capsule as backup for about 260GB of current data (everything on my startup dtive except Downloads folder).

How much data are you expecting to backup? TM will require at least that much space. You can reduce the minimum amount required by excluding some things from backup in TM Options (in TM Prefs).

Remember that TM will back up a new copy of a file if it is modified from the last time it was backed up, so, for example, if you have a 1GB movie and you change it (not merely open but actually change), TM will save another copy. So if you are routinely editing large files, you may want to keep interim versions in a folder excluded from backup.

Let us know how it works for you.

First, did you turn Time Machine OFF in TM Prefs. Probably need to do that.

Select Macintosh HD and choose Get Info from File menu (or press Cmd-I) and note how much of drive is Used (It will show "Used: XXXX bytes (XXX GB on disk)." How much is used?

Then select Time Capsule, and in the Time Capsule folder select the disk image with your computer's name and Get Info. How big is that image?

Going to have to leave in a bit, so here are some more thoughts:

How much free space is now available on your TC drive?

How many sparsebundles (current and previous backups) are on your TC, and size of each?

If you have space, you might go ahead and create a disk image on your TC drive to "reserve" some space.

Why is new backup smaller than older backup? Older backup contains multiple versions of files, so that's probably why. And some of those files may be inside System or Library folders so not apparent.

Keep reviewing Pondini's TM pages for info. I'll be back in about 3 hours.

How much is used on your HD?

Thanks! So you have only about 35GB of data, including System, Libraries, documents, everything.

It's a bit puzzling why Time Machine would give you those alerts in your attempts to reduce the size of your TM sparsbundle.

Are there any other drives attached with might be included in a TM backup (not excluded in TM prefs options)?

Did you make sure TM set to OFF in TM Prefs and try again to reduce its sparsebundle size?

Thanks.

Since you created the image of a certain size, that may be causing the error. I did not have a chance to watch that video all the way through, so I'm not familiar with the whole process. How did you set that sparsebundle to be?

The "old" sparsebundle, is that inside another folder? Sounds like it, and that's as it should be.

Your Time Machine is set to use the new sparsebundle and does so, right? (when turned on)

A restart certainly won't hurt, and might help. Try a restart, and then before turning on TM again try again using the Pondini method to adjust the size of the current sparsbundle.

Well, yes, there are a couple options.

One option is to delete items from the backup in TM's "time-travel" interface, and then use a terminal command to compact the sparsebundle. See here. Turn TM off in TM Prefs before doing this.

Be aware that when you delete items from within the "Star Wars" interface ALL bakups of the particular item(s) (files or folders) will be deleted and there will then be no backups of them until they are backed up again after you finish what you're doing.

However, since all this is fairly new, another option is to close the existing sparsebundle and create a new one to which you can then apply the desired size limit. Then you can use TM's "Browse Other Time Machine Disks" option to access other backups if needed, and trash them when you no longer need them.

Yet another option is to simply limit the existing sparsebundle to its current size and see how things go.