The Apple knowledge base note on this question says to hardwire the Time Capsules and a computer together through ethernet, and transfer the data from TC1 to the computer to TC2, all through ethernet.

I can see how getting 1 GB across this way will be monumentally slow.

However there are these lovely little USB ports on both Time Capsules. Is there a way for me to get the Time Capsule to copy the data from its internal hard drive to a USB external drive? And then vice versa on the other Time Capsule, connecting to it the USB drive with the data from the first Time Capsule?

A related question here might cover one direction, but not the other? And only then if I can find an old version of Airport and the function is still supported by the old Time Capsule with upgraded software.

I am trying the wired ethernet approach, and I see this when copying one of the sparsebundles:

2.61 GB of 661.85 GB - About 2 days

That is with everything wired, and airport on the laptop and the old Time Capsule turned off. I am sharing the old Time Capsule hard drive on the WAN, which is wired to the new Time Capsule LAN. That laptop is on the new Time Capsule LAN.

The wired transfer ended up running at about 48 Mb/s or 6 MB/s. The reason is that the USB-Ethernet dongle I used only supports 10/100 Base-T. No GigE. 48+48 maxed out the 100.

When I went to a Thunderbolt-GigE dongle, the rate went up, but only to 106 Mb/s (13.3 MB/s). The drive in the new Time Capsule can average 1200 Mb/s (150 MB/s) writing. The drive in the old Time Capsule can average 400 Mb/s (50 MB/s) reading. So the GigE is still well shy of what I might expect from USB3, or even USB2.

  • 2
    If a 662GB transfer would take "About 2 days", that's an effective transfer rate of only ~33Mbit/sec or ~4MB/sec (although there's a lot of rounding involved in "About 2 days"). Still, GigE should be able to work much faster than that. Are all devices involved in the transfer capable of GigE and actually connecting at GigE speed? You're obviously doing the copy from a Mac. Does your GigE switch show that (a) the Mac and (b) both Time Capsules are all connected to the network at full Gigabit Ethernet speed? The indicator lights on your GigE switch should tell the story. Commented Jun 30, 2013 at 16:29
  • I now have more data with much less rounding error (it's about 40% of the way through), and the actual transfer rate is about 48 Mb/s, or 6 MB/s.
    – Mark Adler
    Commented Jun 30, 2013 at 17:04
  • 1
    It might go faster if you connect the old TC to the LAN port of the new TC, instead of the WAN.
    – Kent
    Commented Jul 1, 2013 at 0:29
  • It is. "... which is wired to the new Time Capsule LAN."
    – Mark Adler
    Commented Jul 1, 2013 at 14:00
  • 1
    To see if the Ethernet port on the Mac is using GigE, use /Applications/Utilities/Network Utility ("Info" tab).
    – Ashley
    Commented Jul 1, 2013 at 14:14

3 Answers 3


I'd suggest using rsync from the terminal. It may still be slow, however:

  • It should be faster than finder.
  • You can stop the transfer any time. It will resume from where you left the next time you issue the same command.

So, it should both reduce required time and also make it possible to stop it and resume if you actually need to use your computer.

sudo rsync -avPh --delete-after /path/to/original/gromit.sparsebundle/ /path/to/copy/of/gromit.sparsebundle/


  • -a: Archive (be recursive, preserve timestamps ownership etc).
  • -v: Verbose.
  • -P: Show progress and real-time transfer rate.
  • -h: Human readable output.
  • --delete-after: At the end of copying remove any files at the destination that don't exist at the source. This gives you the freedom to continue making backups on your old time capsule without worrying about excessive files being copied to the new one.

Important: The trailing slashes in the two paths are important! If omitted a new dir may be created when you resume the sync (i.e. /path/to/copy/of/gromit.sparsebundle/gromit.sparsebundle).

Also note that the transfer rate displayed with the -P parameter is not accurate when small files (a few KB) are transfered.


Time Capsules are Gigabit Ethernet routers. This means a top speed of 100 MB/s over cable (but is pretty unlikely). It will however be comparable to the speed of USB2, so I think you should try it before dismissing Ethernet.

  • Tried it. See updated question.
    – Mark Adler
    Commented Jun 30, 2013 at 17:11
  • Turns out I'm limited by a 100 Mb/s USB ethernet dongle.
    – Mark Adler
    Commented Jul 1, 2013 at 16:11
  • The GigE dongle about doubled the rate. But that still would put the original attempted transfer at 14 hours at about 100 Mb/s. Well shy of what I would expect for a USB hard drive transfer rate of around 500 Mb/s.
    – Mark Adler
    Commented Jul 1, 2013 at 18:49
  • 1
    "The Mac does not have a built-in Ethernet-port" is relevant and important. Do you see why, now? Also, is there ANYWAY this Mac can communicate with the outside world with anything faster than USB2 (which is usually a LOT slower than a modern drive)? Commented Jul 1, 2013 at 20:57
  • Um, where besides your comment just now did someone say "The Mac does not have a built-in Ethernet-port"? And why would someone say that, given that many Macs have a built-in Ethernet port?
    – Mark Adler
    Commented Jul 1, 2013 at 21:01

The USB ports on the Time Capsules I've seen have type A sockets, so the Time Capsule ("TC") is a "host", which can only be connected to "devices" (eg hard drives, printers, not computers). Apple has a Uses for the USB port of Time Capsule document which confirms this. So it isn't possible to connect a TC directly to a Mac, or to another TC via USB.

It is possible to connect a USB hard drive to a TC, and "archive" the contents of the TC to that external drive, without the data passing through a Mac/PC. This feature was added in the 7.3.1 firmware update: this TidBITS article gives details. The feature does still seem to exist in the current AirPort Utility 6.3: press Archive Disk in the first dialogue shown below to reveal the sheet shown in the second. (I say "does still seem to exist", because I thought I'd read that that feature had been removed, along with several others, in the redesigned AirPort Utility 6, but I must be remembering incorrectly.)

AirPort Utility Disks pane, showing Archive Disk button

AirPort Utility archive sheet

However... although this allows the TC data to be copied to an external USB drive, I believe there is no similar method to copy data from an USB external drive.

So: back to Ethernet.

To see the speed that an Ethernet port on a Mac is currently using, use /Applications/Utilities/Network Utility. See "Link Speed" in the Info tab (1 Gbit/sec, ie "GigE" in the screenshot below.)

Network Utility Info tab

(I originally mentioned this in a comment on the question but thought it would be worth putting into a proper answer, as it seems to have been useful.)

You have seen improved performance from using a Thunderbolt-GigE adapter. I suspect the bottleneck now is probably the processors inside the Time Capsules. (I do remember reading about this, but can't find the reference now, sorry.)

If you are able, I'd suggest this plan:

  1. Take apart the older TC and remove the hard drive.

  2. Plug the hard drive into your Mac using a SATA->USB adaptor, or using a spare drive enclosure if you have one.

  3. Plug the new TC into your Mac using your Thunderbolt-GigE adapter.

  4. You should now be able to see both drives in the Finder.

  5. Copy the files using the Finder, or perhaps SuperDuper! or Carbon Copy Cloner.

(I used a process similar to this when I upgraded the drive inside my TC from 1TB to 3TB recently.)

Here, I'm assuming the processor in the older TC is the main bottleneck... and also that you don't mind voiding the warranty by opening it. This involves removing the rubber base, which is glued on. It is possible to take apart and later reassemble a TC without destroying the rubber base, if you use a hair drier etc to melt the glue and proceed carefully. If you are also willing to open the new TC, connecting both hard drives via SATA->USB adaptors might give you the speediest results... although in that situation, you might find the USB bus bandwidth is the bottleneck.

  • Your first paragraph indicates that you did not understand my question about the use of the USB ports. The question is "Is there a way for me to get the Time Capsule to copy the data from its internal hard drive to a USB external drive? And then vice versa on the other Time Capsule, connecting to it the USB drive with the data from the first Time Capsule?" That is entirely permitted by the USB ports on the Time Capsules, which are in fact intended for connecting hard drives. I don't know what you meant by "your purpose" there.
    – Mark Adler
    Commented Jul 4, 2013 at 15:26
  • The idea of pulling the drive out of the old Time Capsule is a good one. However I didn't want to ruin the appearance of the old one by inadvertently ripping up the rubber underneath while trying to take it apart, since I plan to sell the old one.
    – Mark Adler
    Commented Jul 4, 2013 at 15:29
  • @MarkAdler Apologies: I misread your question. I've edited my answer with some more information, hopefully answering both of your comments here...
    – Ashley
    Commented Jul 4, 2013 at 19:26

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .