How can I limit the amount of space on a Time Capsule used by Time Machine?

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How can I limit the amount of space on a Time Capsule used by Time Machine?

I know that you cannot partition a Time Capsule drive. However, I was wondering about other options for limiting the amount of space used by Time Machine so that I can use the rest of the space for other purposes.

I heard something about creating a disk image on the Time Capsule to limit the amount of space used by Time Machine. If I create a disk image, would TM just use all the space that's not part of the disk image? How do I access the disk image part? Can I manually drag and drop files to it from my Mac like any other external drive? Could I set up the disk image part to work with a Windows computer?

I've also heard things about modifying sparsebundles which I don't know anything about. How does this work? What happens to the space that is not part of the TM sparsebundle? How do I access it? Can I manually drag and drop files to it from my Mac like any other external drive? Could I set up the extra space to work with a Windows computer?

Posted on Jun 29, 2014 9:24 PM

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Answer 1

Niel

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Jun 29, 2014 9:28 PM in response to soonerfan237

1. Time Machine will use up all the space not occupied by disk images.

2. Double-click the dmg in the Finder.

3. Yes.

4. Yes, if it’s formatted correctly, both in terms of the disk image’s file format and the filesystem it contains.

(108783)

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Answer 2

Jun 29, 2014 11:36 PM in response to Niel

Some other things to make note of:

Some disk image formats have a maximum size and only use that size after they have had to expand to actually hold that much data. Make sure you are not using this type of image so you can guarantee the space is reserved. Sparse bundles are like this. I haven't read up on the sparse bundle trick, but I assume it's something to do with setting a maximum size for it.

When you open up the Time Capsule disk, you will first be looking at the normal storage space. When you create an image, there will be a file you click on that mounts another drive that uses space on the Time Capsule. This shows up as just one file unless you open it to see it's contents.

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Answer 3

soonerfan237 Author

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Jun 30, 2014 4:16 AM in response to Niel

Thanks for the reply. So, would it be possible to create a disk image that my Windows computer backs up to regularly. And use the rest as my Mac backup via Time Machine?

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Answer 4

soonerfan237 Author

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Jun 30, 2014 4:17 AM in response to Tom Alperin

Thanks for the reply. So, would it be possible to create a disk image that my Windows computer backs up to regularly. And use the rest as my Mac backup via Time Machine?

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Answer 5

Jun 30, 2014 6:14 AM in response to soonerfan237

How can I limit the amount of space on a Time Capsule used by Time Machine?

It is not easy, but can be done.

See this support article:

http://pondini.org/TM/Troubleshooting.html

See #A8

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Answer 6

Niel

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Jun 30, 2014 8:37 AM in response to soonerfan237

Yes. If you’re using a Windows backup product, it needs to be able to back up to disk images.

(108787)

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Answer 7

soonerfan237 Author

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Jun 30, 2014 9:56 AM in response to Niel

Thanks again. That sounds like it will work.

Basically, I have a Mac with an OSX and Windows partition and I want to back up both partitions to a Time Capsule. I know that Time Machine can't back up both partitions directly so I'm looking for a workaround. I'll use Time Machine to back up my OSX to the Time Capsule. My concern was with backing up the Windows part, but it sounds like I can make it work by creating a disk image on Time Capsule and backing up to that. Does that sound like it will work? Do I create the Disk Image within OSX? Will Windows be able to see it? Will it be formatted to work with Windows?

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Answer 8

Niel

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726,707 points

Jul 1, 2014 8:16 AM in response to soonerfan237

1. Yes.

2. If possible, create the disk image from Windows.

3. Yes.

4. You’ll be asked to choose the image’s format when creating it.

(108856)

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Answer 9

soonerfan237 Author

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Jul 1, 2014 8:21 AM in response to Niel

This might be a stupid question but I don't know much about disk formatting. So it will be possible to format the disk image in a windows format and have the rest of the drive in a Mac format without partitioning?

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Answer 10

Niel

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726,707 points

Jul 1, 2014 8:28 AM in response to soonerfan237

Yes. As I wrote above, you’ll be given the option to pick a format when creating the image; choose a format which the backup program supports out of MS-DOS, FAT32, exFAT, or NTFS.

(108859)

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Answer 11

soonerfan237 Author

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Jul 1, 2014 8:30 AM in response to Niel

Great. That should work perfectly. Thanks for the help.

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Answer 12

soonerfan237 Author

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Jul 9, 2014 6:33 AM in response to Niel

Just got my time capsule. But I can't seem to figure out how to create a disk image as you described. Can you explain the process or point to a place with instructions? I can't seem to find anything.

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