Using Remote File Access to Save Disk Space on Your MBA

NOTE: The most up-to-date steps are available in the following Guide entry: http://guides.macrumors.com/Using_Remote_File_Access_to_Save_Disk_Space_on_Your_MacBook_Air. Please feel free to post your questions and comments in this thread.

As we all know, the MBA has a relatively small hard drive. For me, this started to become a bit of a problem when I copied all 35 GB of my music from my main Mac Pro to my MBA... and suddenly I found myself with a scant 5 GB of free disk space. Not exactly optimal... especially since my Mac Pro has gobs of free disk space just sitting there waiting to be used. So, in my never-ending quest to have universal access to all of my information, the question occurred to me: How can I leave my files on my Mac Pro, but still be able to get to them from my MBA?

On Your Home Network

When you're at home, on the same network, this is easy: You simply set up File Sharing on your server and then create a connection to it from your MBA.

Once you've done that, you can do things like change the iTunes Music folder location in iTunes on your MBA so that it points to the music files on the server, and then use Add To Library to add the music files, which reside on the server, into iTunes. What you end up with is the iTunes Music Library.xml and iTunes Library files on your MBA (a combined 21 MB in my case), but the music files stay on the server (35 GB). So I've saved myself 35 GB of disk space on my MBA.

The same trick can obviously be used for documents, photos, etc. The bigger the files you can keep on the server and off the MBA, the better! You just need to make sure that your MBA and your server can talk to each other, preferably via WiFi, and make sure that your files on the server are easily found (don't bury them too deep in folder structures, basically).

Away from Your Home Network (Secure)

When you leave your home, though, things get trickier. How can your MBA talk to your server if you're not on the same network?

Well, one option is Back To My Mac (BTMM), one of the features in the current release of .Mac. It purports to be an easy way for your two Macs to talk to each other... but I did some experimenting with it last night and today, and I can tell you that it's not as easy as they say to set up. Beyond the fact that you have to pay $100 a year for a .Mac subscription, the biggest issue is that your network routers at both ends (i.e., where your server is and where your MBA is) both have to support UPnP (Universal Plug and Play) or NAT-PMP... and they must be correctly configured to allow you to use one of those two technologies. Find yourself in a hotel or a public WiFi spot where neither of those protocols is in use or where they're using an unsupported router, and your BTMM is suddenly worthless. (Apple won't volunteer this information as plainly as I have stated it here. As far as they are concerned, everyone has UPnP/NAT-PMP routers.)

Since using BTMM is clearly a hassle, I did a little poking around and found an even better solution which only requires changes on your home router. Basically, if you open a specific port on your router and forward that port to your Mac Pro server, you can get to the server from anywhere you can access the Internet with your MBA. I can't tell you exact steps for your particular router, but here are the basics:

1. On your router, configure port 548 to point to the internal IP address of your Mac server (a Mac Pro, iMac, Mac mini, or some other Mac that's always home and on) for both TCP and UDP. For example, your Mac server might have an IP address like 192.168.1.1.

2. On your Mac server, go into System Preferences > Sharing and make sure that File Sharing is turned ON. Also, click Options under File Sharing, and make sure that "Share files and folders using AFP" is turned ON, and make sure the list of Users includes YOUR account with Read & Write access.

IMPORTANT!: You also need to set the access for "Everyone" to "No Access". If you fail to do this, someone might potentially be able to access your server's files simply by directing their Mac to connect to yours. The only account(s) that should be permitted access are "name" accounts (your name and other accounts you specifically created).

3. You will need to know your home network's external IP address: This is the IP address that's assigned to your home by your cable company or ISP. You can usually get this IP address from your router's control panel, or by going to http://checkip.dyndns.com/. (Before you ask: Your external IP address does NOT start with "192.168". It will be something totally different.)

NOTE: You could also install a Dynamic DNS client on your Mac and use it to associate a domain name like "www.myhomedomain.com" to your external IP address. This costs a little, but it eliminates the need for you to have to fiddle with IP addresses, especially if they ever change. You can get a Dynamic DNS client here: http://www.dyndns.com/support/clients/mac.html

That's all you have to do at home.

When you're on the road, you can connect your MBA to your home Mac server using these steps:

4. In the Finder, click Go > Connect To Server.

5. In the Server Address box, type your home system's external IP address. For example, "123.123.12.123". Or, if you have a domain name that points to your home system, you can type that: "www.myhomedomain.com", for example.

6. Click Connect.

A password prompt dialog box will appear and ask you for your name and password. Select "Registered User", and then enter your user name and password from your Mac server. If you want, you can check the box for "Remember this password in my keychain".

7. Click Connect.

Now you'll get a list of all of the shares on your Mac server.

8. Select the share(s) you want to connect to, and click OK.

Voilà! You are now connected to your home Mac server from your MBA. You can access files, copy files back and forth between your MBA and your server, delete files, whatever you want, as long as your MBA remains network-connected. The next time you go to connect, it should go even more quickly (especially if you save your password in your keychain, and if you add your home IP address/domain name to your list of Favorite Servers in the Connect dialog box).

Away from Your Home Network (Even More Secure) -- Added 3/3/2008

I didn't post this info earlier, because I wasn't sure it would work... but this weekend I was able to confirm that it does. There are two differences between this method and the Secure method shown above:

1. On your router, configure a port number that you choose (for example, 5678 -- I recommend using a high port number to prevent conflicts) to forward to port 548 of the internal IP address of your Mac server (a Mac Pro, iMac, Mac mini, or some other Mac that's always home and on) for both TCP and UDP. For example, your Mac server might have an IP address like 192.168.1.1.

5. In the Server Address box, type your home system's external IP address, plus a colon and the port number you specified in step 1. For example, "123.123.12.123:5678". Or, if you have a domain name that points to your home system, you can type that, plus a colon and the port number you specified in step 1: "www.myhomedomain.com:5678", for example.

Setting your router to perform port forwarding in this manner, rather than just relying on the home server's login security, provides an additional layer of security that will prevent unauthorized users from accessing your home server: Not only would they have to know your user name and password from your home server, but they would also have to know what port number to use, not just the default 548 port number. If they can't even guess the right port number, they don't even get a chance to try your user name and password.

Once You've Set Everything Up

Once the connection is established, it will also work for programs like iTunes. As I type this, my MBA is connected to a neighbor's open WiFi network (so it's "away from home"), connected through that to my Mac Pro server through the Internet. I'm using iTunes on the MBA to play a copy of a-ha's Take On Me which is stored on my Mac Pro server. I can access my entire music collection in this manner. (The only downside of doing this is that file transfers are limited by network speed. So when I go to another song, it takes a few seconds to transfer the bytes to iTunes on my MBA before the song actually plays. Network hiccups can also be a bother. But at least I can get to the files!)

Those of you who have MBAs and who have a little expertise shouldn't have any trouble following the above steps. Hope you enjoy them, and as always your feedback is welcome!

camarobh said:

I have been trying to come up with a solution for Podcasts while away from my iMac. I have my iTunes library on my iMac at home. I travel with my MBA. I am not interested in transferring the music files, but I am very interested in Podcasts. While I am away I want to retrieve the latest Podcasts that I subscribe to and sync them to my iPhone for the airplane ride home. As it is now, I sync up before I leave, but listen to them all while away and when I get home am all backed up with episodes I have missed.

Basically I want to download new episodes while I am away on my MBA and have it synced with the episodes on my iMac.

How can I keep the two iTunes libraries in sync for just Podcasts? Will your solution support that?

Thanks!

Click to expand...

If the Podcasts are automatically showing up on your Mac server each day, here's what you would do:

1. At home, you'd need to configure your MBA's iTunes to store all of its music files (Preferences > Advanced > General > iTunes Music folder location) on the server.

2. Then, you'd use Add To Library to add all of the music that's on the server to your MBA iTunes library. This is what I did, and the result is that the music files stay on the server, but the MBA can access all of them. This should also work for podcasts (I know it works for movies).

3. When you are on the road, you'd connect to the Mac server using the steps I wrote above.

4. Then, you'd use Add To Library again to add just the new podcasts. They'd stay on your server, but they'd be accessible on the MBA.

5. Once they're accessible on the MBA, you can then sync them to your iPhone.

You bring up a good point: It's not enough to just share the iTunes library from the server to the MBA, because if you do that, all you can do is to play the media. You can't sync music from a shared library to an iPod or iPhone. That's why you actually need to connect to the server and let your iTunes use the music files that are stored there, versus just talking to the server's copy of iTunes.

Basically, each machine (the server and your MBA) would maintain its own iTunes library, but they'd share a common repository of music files, podcasts, and movie files.

I think that's what you're looking for?

JasonBourne9 said:

clayj

Thanks for the helpful post. On a related note, I have actually been successful with back to my mac over my evdo card. I haven't tried it over a different wifi or hotel network (haven't traveled with my MBA yet) but from home, using the EVDO connection, I can see my home computer drives, copy files, even screen share (albeit not at blazing speed). So I guess both my Airport Extreme router and Verizon EVDO card have UPNP support.

Click to expand...

Yeah, that would be my guess. For me, the dealbreaker was that I don't know if everyone in my family has a UPnP-compatible router, and I don't want to have to fight that battle each time I go somewhere. Opening port 548 and using the steps I wrote above will save a lot of headaches.

dimensiondvdrob said:

to the OP:

if you use this command, how will you designate a certain 'repository' for all your music to get directed to? what i mean is if you do this command, itunes will ask where to add from, then index everything to my laptop, but then, it's stored on the internal disk of my laptop (maybe not the songs, but the index). then how do i designate where itunes will store music, etc. when i buy or download something? i certainly dont want to store it locally on my laptop.

thank you.

Click to expand...

Here's how my 'repository' is set up:

1. On the server, I used iTunes > Add To Library and added in all of my music. I let it go to the default location, which is (IIRC) Macintosh HD:Users:MyName:Music:iTunes:iTunes Music. So the server is a straight-up standard implementation of iTunes, nothing odd about it.

2. On the MBA, I rejiggered iTunes (using Preferences) so that its iTunes Music folder location was ServerName:MyName:Music:iTunes:iTunes Music... it's pointing to the exact same physical location as iTunes on the server, but the pathing is different since I am coming across the network. I also made sure that my user name and password for the server share were stored in my keychain, so I'm never prompted for that on the MBA. Then I used Add To Library to add the music files on the server into my library... the result is that the music stays on the server, and iTunes adds those file paths to its library.

The result of these two actions is that both copies of iTunes are using the same song files, but they each maintain their own iTunes library files. If you add new songs, you would want to add them on the server first, then add them on the MBA. In both cases, I would be using Add To Library.

(Why? Because I rip all of my music in Windows, using RealPlayer, into WMA format; then I use iTunes in Windows to convert them to AAC, then I import them into iTunes on the Mac server, then I import them into iTunes on the MBA. Convoluted process, but it gives me the best results for sharing music on my Xbox 360s, and RealPlayer has superior file naming and organization capabilities over WMP and iTunes.)

I don't buy music from iTunes, so I really don't know where it would store a downloaded song. My inclination is to think it's going to try to stick the song on the repository on the server... so if you buy music on your MBA, it would probably be a good idea to make sure you are connected to your server first. Someone will really need to test this, though.

LouTreize said:

Wow, ClayJ created two of the most informative threads on MacRumors. This and this...

Sticky...please


I don't even own a Macbook Air...but if and when i do, this would be the first place to look. Thanks ClayJ for your hard work.

Click to expand...

Lou, thanks!

As a bonus, I have just added information (to the original post) about how to make your remote file access even more secure than it was before... check it out when you get a chance!

Terwal said:

clayj, this is another amazing post. For a newbie like me, the posts you write are extremely useful because they deal with tricky issues and... I understand them ! or so I think !!

Click to expand...

My pleasure! Actually, in a former job (Microsoft) I used to write technical articles all the time, so the article writer in me appreciates being let out occasionally to do some serious writing.

Terwal said:

One question though regarding using the same trick with photos:

For the first time last night, I imported my pictures from my external drive onto iPhoto. On my MBA, I see the iPhoto Library (which is roughly 5GB big). Therefore it seems that the pictures were actually copied from my external drive onto my laptop ?

If it is the case, how could I use the set up you have described (having a "light" library on the MBA and storing the "heaving" photos on an other computer) ?

Thanks for your advice.

w.

Click to expand...

Hmm. It doesn't look like iPhoto provides an option similar to iTunes, which allows you to specify the location where your media (music, movies, etc.) should be stored. For iPhoto, as near as I can tell, it just jams everything into the "iPhoto Library" file on your machine.

I was referencing "photos" more in the way of saying "You can see them on the other machine and browse them". Once you start involving an app like iPhoto, you become totally dependent on what that app will allow you to do. iTunes is flexible about that; iPhoto appears not to be.

phatjoe said:

"Clayj" thanks so much for this awesome post.

HOW DO YOU KNOW SO MUCH ABOUT THIS STUFF!

Click to expand...

You're welcome.

And it's actually not so much a question about how much you know when you start... when I started writing this thread and the thread about doing a clean OS X reinstall, I really knew very little about the subjects in question. But I knew what I wanted to do (e.g., save hard drive space), and I knew other stuff (like how to use port forwarding on a router), so then it was just a question of sitting down and running through things, Googling for answers to questions I came up with, and testing things to make sure they worked as expected. By the time I was done doing all of that, I knew fairly well how all of the things work that I was writing about.

After that, it's just a matter of thoroughly documenting everything you do, documenting any problems or bugaboos you find, and testing stuff before you publish what you wrote. (How to do some of that testing: Temporarily "borrow" your neighbor's WiFi network so you can test your configuration from "outside" your network... or go to the Apple Store and test from there. Makes for a good excuse to go to the mall.)

It helps if you actually like experimenting with computers, like I do.

I've actually done quite a bit of writing about technical stuff over the years... one of my previous jobs, when I worked at Microsoft, was writing Knowledge Base articles. I'm pretty good at describing problems, writing up causes, and documenting solutions in a way that is clear, concise, and precise. If you're interested in seeing some of the stuff I've written, go to http://www.clayj.com/html/ClayArts.htm. (Please bear in mind that most of the articles linked there are nowhere near as detailed as stuff I've written here, because the problems I was writing about were usually much simpler.)

bluetooth101 said:

Sorry,newbie here. i got an Imac at home with a MBA for travel. The Imac is running on Tiger and the MBA on leopard. I've tried the steps given but can't get it to work. Anyone have the luxury of time explaining the steps of completing this is more details? For example, Step 1...Step 2....
Sorry again...sigh

Click to expand...

Which part doesn't seem to be working? Are you able to get the port forwarding set up correctly on your router? Do you receive any error messages? (Please don't post any confidential information like your home system's IP address. We don't need to know that and you don't need to expose yourself to any hackers.)

thehuhman said:

Thanks, clayj. Gonna give it a try. (was wondering what to do this weekend)

Click to expand...

Remember that an easy way to test your access from the outside is to "borrow" a neighbor's WiFi network and connect your MBA to that, rather than to your home network. That way you can access your home network from the "outside", just as if you were away from home.