Accessing the Time Capsule while travelling with your MBA

Preliminary Info

Please note that I am not actually using a Time Capsule in this test, but an AirPort Extreme Base Station (AEBS) with a 320 GB USB hard drive connected and shared out with the following settings in the Disks > File Sharing dialog box:

Enable file sharing: checked
Secure Shared Disks: With base station password
Guest Access: Not allowed
Share disks over Ethernet WAN port: checked

This should be functionally equivalent to a Time Capsule, with one notable exception (see below).

With this configuration, I perform the following steps on my MBA, which is connected to the Internet via a neighbor's open WiFi network (which means my MBA is "not at home"):

1. In Finder, click Go > Connect to Server.

2. Type in the proper URL/IP address for my home network (e.g., afp://www.myhomedomain.com or afp://123.123.12.123) with no port number specified. I am not trying to connect to a machine inside the firewall, so port forwarding is not necessary and I do not need to specify port 548.

3. Click Connect.

4. I am prompted for my user name and password. I type in my own user name, and the password which I set up on the AEBS. (Note that this is not necessarily the same as my password on my Mac Pro or MBA. The AEBS/Time Capsule has its own password, which you set on the Airport > Base Station screen, right below where you set the Base Station Name.)

5. Click Connect.

Voilà! I am now connected to the USB hard drive which is connected to my AEBS, via the Internet. The Shared section of the sidebar in the Finder shows the Base Station Name of the AEBS as though it were a server name, with the hard drive contents listed on the right side of the window.

So this is all pretty much what I would have expected so far... I can read the drive, copy files to and from it, open files, etc. But the big question remains: Can I enable Time Machine functionality to use this hard drive which I am connected to via the Internet?

6. Go to System Preferences > Time Machine.

7. Click Choose Backup Disk.

EXCEPTION: No disks are shown.

Now, here's the problem: We know that Apple has (stupidly) hobbled the use of Time Machine to a USB drive on an AEBS... so this last part really wasn't going to work, even if my MBA was on the same network as the AEBS/USB hard drive. In fact, I can confirm that this is the case: If I put my MBA back on my home network and then connect it to both my Mac Pro and my AEBS, Time Machine will detect hard drives on my Mac Pro that I've connected to; but it will not detect the shared hard drive on my AEBS.

So, someone still needs to test this properly, with an actual Time Machine. My original suspicion, however, still stands: I do not believe that you can use the actual Time Machine functionality across the Internet.

My challenge to someone out there who has a Time Capsule and the technical wherewithal to try to connect to it from across the Internet: Follow the steps I've written above and let us all know if you can enable Time Capsule functionality when your MBA (or other Apple notebook) is connecting to it via the Internet.

Time Machine Over Internet = YES*

Well, I may have to retract what I said earlier about Time Machine not working over the Internet. I am pretty sure now that it will, with caveats. Here's what I did to test this:

1. I connected my MBA to my neighbor's open WiFi network, so that my MBA is "away from home".

2. I then connected to my Mac Pro via the Internet, using my home domain name and secret port number. I selected one of my Mac Pro's hard drives to connect to, so it shows up in the Finder under Shared.

3. I went into System Preferences > Time Machine > Choose Backup Disk.

Result: After a few seconds, the remotely-connected hard drive showed up in the list of hard drives!

Based on this, Time Machine can connect to a hard drive over the Internet. It seems like it would probably be able to connect to a Time Capsule as well, as long as you establish the connection between your MBA and your Time Capsule first...

... and here's where that asterisk from above comes into play. You have to create the connection to the Time Capsule/Time Machine before it will work... and even then it's at the mercy of network conditions (speed, dropouts, etc.). Time Machine may do a lot of shuffling of data back and forth, and I would be very concerned about how well the system would perform under those circumstances. All that network traffic as Time Machine writes files up to the Time Machine repository is gonna drain your MBA's battery fairly quickly. (Not to mention, any changes made while disconnected from Time Machine might not be preserved properly.)

So, it looks like you can use Time Machine over the Internet, to either a Time Capsule or a shared hard drive on a server in your home. But do I think it's a good idea? Let me answer you this way:

I'm not gonna do it.

EDIT 3/19/2008: Apple has now enabled using a USB hard drive, connected to an AEBS, as a Time Machine repository with the AEBS 7.3.1 firmware. AEBS + USB HD = Time Capsule, basically. Testing to follow.

how do you find the url/ip for the drive connected to the base station?
does this work even without your computer at home turned on?

clin86 said:

how do you find the url/ip for the drive connected to the base station?
does this work even without your computer at home turned on?

Click to expand...

You can find out your home network's external IP address by going to http://checkip.dyndns.org. In my case, I happen to have a domain name which is dynamically mapped to whatever my IP address is, so I can get to my home network using just that domain name. (This costs about $50 a year to do. Check dyndns.org for details.)

And no, your home machine has to be turned on in order to access it. An AEBS or Time Capsule would presumably always be on.

clayj said:

You can find out your home network's external IP address by going to http://checkip.dyndns.org. In my case, I happen to have a domain name which is dynamically mapped to whatever my IP address is, so I can get to my home network using just that domain name. (This costs about $50 a year to do. Check dyndns.org for details.)

And no, your home machine has to be turned on in order to access it. An AEBS or Time Capsule would presumably always be on.

Click to expand...

I am new to mac.. so some of my qns might be silly..
- Cant I access my HDD connected to AEBS without any home machine?
- Does ISP dynamically change the IP address? If so, how can i know the new IP address if I am away from home?

It could be interesting to have it really work for say.. the ultimate road warrior who crashes his HD miles from home and who wants to do a restore..

But if it works the speed would be...frighteningly slow i'm afraid..

Patriiick said:

It could be interesting to have it really work for say.. the ultimate road warrior who crashes his HD miles from home and who wants to do a restore..

But if it works the speed would be...frighteningly slow i'm afraid..

Click to expand...

Yes. Time Machine is undoubtedly going to be expecting a "fat", high-bandwidth connection between your Mac and the Time Machine repository; either they should be on the same machine, or they should be on two machines on the same network connected by a fast network connection. Trying to use Time Machine across the "thin" connection of the Internet is just asking for trouble.

sidharth80 said:

I am new to mac.. so some of my qns might be silly..
- Cant I access my HDD connected to AEBS without any home machine?
- Does ISP dynamically change the IP address? If so, how can i know the new IP address if I am away from home?

Click to expand...

1. Yes, you should be able to do this. However, you will need to configure the AEBS at some point, and that will require a home machine during the configuration part.

2. They can, unless you pay for a static (fixed) IP address. It's been my experience that I will have the same IP address for months or longer, as long as nothing funky happens with my cable modem or anything. But not wanting to risk a problem due to an IP address change, I signed up for a domain name which gets its IP address from a dynamic DNS client installed on one of my home machines. That way, if my home network IP address does change, my domain name will update automatically.

clayj said:

But not wanting to risk a problem due to an IP address change, I signed up for a domain name which gets its IP address from a dynamic DNS client installed on one of my home machines. That way, if my home network IP address does change, my domain name will update automatically.

Click to expand...

Incidentally you can do this for free if your router supports dynamic DNS. You'd have to check your router configuration and/or manufacturer to see if it does. Then you just set up a free account with dyndns.org and enter your signon details into your router. There are also free clients for PC's (and I assume Macs) that can do this if your router can't.

And yes, I know this is a thread about Time Capsule, but you can have a Time Capsule on your network behind another router (I do this with an AEBS using it as an 802.11n bridge effectively).

clayj said:

In my case, I happen to have a domain name which is dynamically mapped to whatever my IP address is, so I can get to my home network using just that domain name. (This costs about $50 a year to do. Check dyndns.org for details.)

Click to expand...

DynDNS is free for up to 5 host names and as long as you update the host name every 90 days or so. They have a mac client if your router doesn't support it.

Just select "Dynamic DNS" under services and it will map your an IP to a hostname like "example.getmyip.com" that you can select.

Never had to pay them a penny, even though they give great service.

izibo said:

DynDNS is free for up to 5 host names and as long as you update the host name every 90 days or so. They have a mac client if your router doesn't support it.

Just select "Dynamic DNS" under services and it will map your an IP to a hostname like "example.getmyip.com" that you can select.

Never had to pay them a penny, even though they give great service.

Click to expand...

Yeah, I forgot that they offer free domain names as long as you use a domain name off their list. I prefer to have my own dedicated domain name, hence the cost. I also have MailHop MX Backup through them so that my e-mail doesn't get lost during those rare times (knock on wood) when my cable service goes out or my Exchange Server is offline.

oh i thought u guys said you need a 2nd computer at home turned on to access the drive plugged into the base station. so now is it possible to have only 1 macbook air and still access your drive while you're outside?

Terwal said:

How much did you say was the cost for your own domain ? Thx.

Click to expand...

Through DynDns.org, it's something like $30/yr for the custom DNS (the part that actually points you at the right spot when you use your domain name) and $15/yr for the domain name itself.

And clin86, yes: You don't actually need another machine at home if you've got a Time Capsule or AEBS with USB hard drive attached.

Thanks for the help everyone!

I'm about to set up my Time Capsule but have a question I haven't seen answered:

Can I split the signal coming from the cable modem --taking one line to a router (Vonage phone and Slingbox) and the other going to my Time Capsule. I don't want to use the TC in bridge mode and would like to have it as the only router/firewall on the line.

Thoughts for a better route?

i tried it but it says error code -43 abd there was an error connecting to the server. please check server name or ip address. i just typed in my ip address as it is on the website you guys provided.
am i doing something wrong?

clin86 said:

i tried it but it says error code -43 abd there was an error connecting to the server. please check server name or ip address. i just typed in my ip address as it is on the website you guys provided.
am i doing something wrong?

Click to expand...

Are you "at home", with your notebook on the same network as the AEBS/Time Capsule? Or is your notebook "away from home", on a different network? If you're "at home", you may not be able to connect to the AEBS/Time Capsule using the external IP address you got.

As I did in the other thread of clayj's, I'd throw in a suggestion for a low-cost SSL VPN box. They're available from Netgear, Zyxel, etc.

What SSL VPN does is to create an encrypted virtual private network tunnel over SSL, the same protocol used for buying stuff online - and wherever you are, while hotels may block other protocols / ports they're highly unlikely to block SSL. Practically speaking what it means is that you crank up Firefox and point your browser to your home IP / DynDNS address (SSL certificates are an additional expense, but most boxes should allow you to use self-signed certificates) to access a login page your home. Log in, and you're at home.

It's a comparatively fuss-free and easy way to establish a direct link to your network, with your connected notebook becoming a part of your home network. For networking n00bs there might be a setup learning curve, but it can't be insurmountable. This way there's also no need to expose ports which aren't properly secured to the Internet.

away from home.

clin86 said:

i tried it but it says error code -43 abd there was an error connecting to the server. please check server name or ip address. i just typed in my ip address as it is on the website you guys provided.
am i doing something wrong?

Click to expand...

I am also facing the same problem. I hooked on to my neighbour's wi-fi and tried accessing my ip address, but it gives the same error.
fyi.. I am actually using a trendnet router and was trying to see if i m able to connect to the IP address and see how it works... before i take the plunge and buy the time capsule.

Do i need to tweak any other setting?

Great thread, and thanks for the tips clayj very helpful. This is exactly what I've been wanting to do since I've gotten my MBA. I'll have to try this as I have a similar setup at home.

AEBS + USB Hard Drive = Time Capsule

OK, it turns out that today's release of the 7.3.1 firmware for the AirPort Extreme Base Station (AEBS) now allows you to use the Time Machine functionality with a USB-connected external hard drive. In essence:

AEBS + USB hard drive = Time Capsule (of whatever capacity your HD has)

Because of this change, I can now properly test Time Capsule/Time Machine functionality with my MBA across the Internet. I'm currently setting up a 320 GB USB HD as shared on my AEBS and I will be configuring my MBA to do backups there. As soon as I have some information/results to report, I will post them here.

clayj said:

OK, it turns out that today's release of the 7.3.1 firmware for the AirPort Extreme Base Station (AEBS) now allows you to use the Time Machine functionality with a USB-connected external hard drive. In essence:

AEBS + USB hard drive = Time Capsule (of whatever capacity your HD has)

Because of this change, I can now properly test Time Capsule/Time Machine functionality with my MBA across the Internet. I'm currently setting up a 320 GB USB HD as shared on my AEBS and I will be configuring my MBA to do backups there. As soon as I have some information/results to report, I will post them here.

Click to expand...

Geez, of course! I just broke down and bought a Time Capsule last night. Now of course they release this update (I have 3 AEBS already).