Is it possible to use Back To My Mac DNS or routing information from the command line?

Solution 1:

This has changed a little with 10.7 and you'll want to note that this uses IPv6 almost entirely so test with ping6 and traceroute6 to debug things.

It's no longer done via @computername.mobilemename.members.mac.com, it's now done via members.btmm.icloud.com, and its no longer as simple as your mobilemename.

Step 1: Find out your iCloud BTMM domain

Either of these commands will provide your BTMM domain:

# dns-sd -E
# mDNS -E

The output is formatted slightly differently, but what you're after is the numeric ID, it'll be something like 12345678.members.btmm.icloud.com.

Step 2: List Computers

You can use these tools to browse that domain for services, e.g. for ssh servers:

# dns-sd -B _ssh 12345678.members.btmm.icloud.com

Or if you already know the hostname just access it directly as computer-name.12345678.members.btmm.icloud.com. (Any spaces in your computer name will be hyphens in this domain).

You can only access this from a computer that is also set up for BTMM on the same account, because this hostname will resolve to an IPv6 address that is really the end of an encrypted network tunnel between your BTMM computers.

If you want to see the IPv6 address for a specific host, you can type

# dns-sd -G v6 computer-name.12345678.members.btmm.icloud.com

And it'll output something like:

17:37:47.504  Add     2  0 computer-name.12345678.members.btmm.icloud.com. FD11:993E:64AE:4DEA:011F:FBD1:F444:11A1%<0>  152

Step 3: Connect

# ssh [email protected]

Note

I'm not sure if that number will ever change, so you may or may not need to repeat Step 1 at some point later on...

Solution 2:

I read a few articles on the underpinning of Back To My Mac and supposedly some people have effectively connected via ssh, check out the discussion contained in this Macworld post.

The best post in the thread is as follows:

Use the following format for connecting as a differnent username:

ssh [email protected].

If you do this regularly and wish to save having to use the username all the time for ssh and scp then create a file called ~/.ssh/config with contents like the following:

Host hostname.username.members.mac.com. User user.name

Host host2.some.domain.com. User username2 Port 2222 LocalForward 3389 internal-pc:3389

The second host in this file also includes using a port other than 22 and allowing access to a Windows computer called internal-pc with Remote Desktop by connecting to localhost with the Remote Desktop Client.

Now obviously Apple has switched .mac to MobileMe, so I dont know if that has switched to .me.com, and frankly I dont have a MobileMe account to test it.

Edit: Another interesting post you may want to try is at the veery bottom

Turns out it is even easier! :P

just open the Terminal go to Shell > New Remote Connection...

then choose ssh and there you have your BackToMyMac Computer listed (if the OS sees it).

type in your username and click connect.

voila, you can even see the connection string used. And you can also use ftp/sftp... from this dialog to your remote Mac.

Way easier than typing in some shell command like suggested in the original tip.