ISP-In-A-Box: The $500 Mac mini (WebDAV and Web Folders 101)

Microsoft deserves a lot of credit for popularizing the idea of Web Folders, but the open source movement gets the accolades for making WebDAV work reliably across all the computing platforms. If you didn't already know, WebDAV stands for Web-based Distributed Authoring and Versioning. Simply put, it is an HTTP protocol extension that allows people anywhere on the Internet to collaboratively edit and manage documents and other files using the same protocol and port used for surfing the web. In the Mac world, WebDAV provides a Disk Volume on your Desktop that "looks and feels" like any other networked hard disk. In the Windows world, WebDAV provides a Web Folder which can be used like any other mapped drive in Network Neighborhood. If you're still a little fuzzy about the WebDAV concept, think of how you link to another drive on your local area network. WebDAV gives you the same functionality across the entire Internet with virtually the same ease of use. Depending upon user privileges, of course, you can copy files to and from a WebDAV volume, and the protocol imposes versioning control through file locking to assure that multiple people don't change the same file at the same time. Panther and Tiger versions of Mac OS X provide both a WebDAV client and server, and today we'll walk you through configuring and using both the client and the server on your Mac. Because of the number of folks that also use Windows machines at the office, we'll also briefly touch upon how to access your Mac WebDAV resources and set up a Web Folder from a Windows XP machine.

HOW-TO Use the WebDAV Client on the Mac. We're going to start by walking through the set up process for connecting to a WebDAV server resource anywhere on the Internet. To connect to a WebDAV resource from a Mac, press Command-K from Finder. Then enter a Server Address in the following format: http://192.168.0.103/dav/. This tells Finder to use the HTTP protocol to establish a link to an IP address and folder that you designate. You also can use a fully-qualified domain name in lieu of an IP address. Typically, you'll be prompted for a username and password, and then a new volume will appear on your Desktop which can be used just like your local hard disk. When you finish using the resource, CTRL-Click on the volume and Eject it. It's that simple.

HOW-TO Use Web Folders on a Windows PC. The Windows process is a bit different as you might expect, but the results are the same. Once connected, you'll have a mapped drive that can be used just like any other network drive. The simplest way is to map a drive (see inset). To access Web Folders and save your settings, we're going to use the Add Network Place Wizard. You can access it in several ways. Either Right-Click on Network Neighborhood and choose Map Drive. Or from My Network Places, choose Add a network place. Or from Windows Explorer, choose Tools->Map Network Drive. Now click "Sign up for online storage or connect to a network server" at the bottom of the window.

When the Add Network Place Wizard appears, you'll be prompted for where to create the network place. Select "Choose another network location" and click Next. For the Internet address, use the same syntax as on the Mac: http://192.168.0.103/dav/ and click Next. Give your network place a name and click Next then Finish. Your new Web Folder will now appear in My Network Places. Just click on it to connect. Here's the gotcha with WebDAV on the Windows platform. If you access a Web Folder by IP address, when you're prompted for a username and password to log in, the username must be in email format: john@doe.org. Another "Better Idea" from our friends at Micro$oft. So when you create usernames on your Mac, keep this in mind if you want Windows users to be able to access the resources reliably. It doesn't matter what the email username or domain is, but it has to be in email format. When you finish using a web folder, be sure to disconnect. Open Windows Explorer, choose Tools->Disconnect Network Drive, and select the Web Folder you wish to disconnect.

Connecting to a WebDAV Resource. We've temporarily set up a sample WebDAV server on one of our Tiger-enhanced Macs so that you can experiment with WebDAV access from your favorite Mac, Linux, or Windows machine. For reasons which should be obvious, we've disabled writing to our WebDAV server only because we didn't want our hard disk filled up by some anonymous bozo in the middle of the night. We're also going to provide a single username and password for everyone to use. It should be stressed that neither of these scenarios is typical. First, the usual purpose of a WebDAV server is to facilitate collaboration which means all authorized users should be able to read and write to the volume. Second, you usually don't provide access to a WebDAV server for anonymous users. That's what web sites are for. But this is Wiki World, and we wanted to show you how these things are put together before you roll your own. So bear with the constraints recognizing that, when you set up your own WebDAV server, it will be much more robust.

To access the system, follow one of the client access methods outlined above. The web address using Windows is http://webify.us. For Macs, use http://dav.webify.us:82. When prompted for a username and password, use bozo for the username and forlife as the password. If you have problems with the username on a Windows PC, use bozo@webify.us. Don't forget to disconnect when you are finished playing. NOTE: This system (only) will be down for a move to its new permanent location from Thursday afternoon, May 26 until Saturday morning, May 28. Our apologies.

That about covers using a WebDAV client. For step-by-step instructions on creating your own WebDAV server on your Mac, here's a reprint of the article from our former Tiger Vittles site.

ISP-In-A-Box: Building a WebDAV Server for Remote Access

Ever wished you had several gigs of off-site disk storage so you could safely back up all your most important data and use it for remote access or collaboration. One option, of course, is a .Mac account which gives you 125MB of iDisk storage space and other goodies for $99 a year. You can increase your iDisk to a gigabyte for an additional $49.95 a year, a bargain compared to some commercial sites. Here’s another approach that’ll save you hundreds of dollars a year. Find a friend with a Mac and an Internet connection and swap several gigs of storage space on your friend’s Mac for several gigs of storage space on yours. Then follow along here, and we’ll show both of you how to build and use WebDAV servers to do exactly what the commercial firms are doing. And you can use the Apache software that’s already installed with Mac OS X Tiger.

As you now know, WebDAV stands for Web-based Distributed Authoring and Versioning. Simply put, it is an HTTP protocol extension that allows people anywhere on the Internet to collaboratively edit and manage documents and other files using the same protocol and port used for surfing the web. In the Mac world, WebDAV provides a Disk Volume on your Desktop that “looks and feels” like any other networked hard disk. In the Windows world, WebDAV is called Web Folders. They can be used like any other mapped drive in Network Neighborhood. If you’re still a little fuzzy about the WebDAV concept, think of how you link to another drive on your local area network. WebDAV gives you the same functionality across the entire Internet with virtually the same ease of use. Depending upon user privileges, of course, you can copy files to and from a WebDAV volume, and the protocol imposes versioning control through file locking to assure that multiple people don’t change the same file at the same time. Panther and Tiger versions of Mac OS X provide both a WebDAV client and server. Nerd Vittles walked you through configuring and using the WebDAV clients. So let’s tackle the WebDAV server setup now. This works with Tiger or Panther by the way.

In a nutshell, the WebDAV server setup goes like this. We’ll create a new subdirectory in the web server’s storage folder which we’ll use for WebDAV read and write access. Then we’ll set up a username and password system to support WebDAV access. Next we’ll activate the WebDAV mods in Apache which already are installed on your Mac. We’ll then reconfigure Apache a bit to support WebDAV formatting. And finally we’ll restart our web server and presto, WebDAV. You don’t need to be a Rocket Scientist to do this, but you do have to get your hands dirty with a command-line editor, Pico. If you’ve followed other Nerd Vittles tutorials, then this one will be a breeze. Just be sure you edit carefully and, if something does go wrong, copy your backup Apache config file back over the edited one and try again. Apache errors don’t get reported in System Preferences->Sharing when you activate your personal web server. If you have problems and want to see what’s going on, activate and then run WebMin (which we previously covered at Nerd Vittles and upgraded here last week for Tiger). Using your browser, access WebMin and choose Servers->Apache Webserver. Then start and stop the web server from there. Errors will be reported with the line number in the config file that’s causing the problem. Ctrl-C in Pico will tell you what line number you’re on in the config file. If this sounds like I’ve had recent experience, you’d be correct. But you won’t have to pull your hair out. I’ve already done that with mine.

Creating a WebDAV Folder. Open a Terminal window, and switch to root access: sudo su. Then navigate to the root of your web server folders: cd /Library/WebServer/Documents. Create a new WebDAV folder: mkdir dav. Change the permissions of the folder’s group to match the Apache group: chgrp -R www dav. If you want to provide write access to users who connect to your WebDAV folder, then change the permissions to allow it: chmod 775 dav.

Building a Password File. We already built a password file in the Web Sites 101 tutorial on Nerd Vittles. We used that password file to manage web site access to various web directories. You probably don’t want to use the same password file for WebDAV unless you are building this just for yourself. The only trick to password files is you want to put the file where Apache can read it but your web visitors cannot. And you want to be careful not to insert blank lines in the file with just a colon. That basically lets everyone in. The format for the file is username:password, each on a separate line. And the passwords are encrypted. Here’s how to do it.

Open a Terminal window and switch to root access: sudo su. Now move to the directory where we’ll put the password file: cd /usr/local. We’re going to name this password file dav.pw so we can remember what it’s for. To create the file and erase any existing file without warning type: htpasswd -c dav.pw admin. Think up a password you can remember, and you’ll be prompted to type it twice. Now let’s verify that the file was created: cat dav.pw. You should see the word admin, then a colon, and then your encrypted password. To add additional users to the file, just type: htpasswd -m dav.pw username where username is your next user. You’ll be prompted for the password. Remember, if you accidentally use the htpasswd -c syntax a second time, you will overwrite your existing file and all of its entries. So be careful. Finally, remember to make duplicate entries using full email syntax for the username to assure that Windows users can access your DAV resources: htpasswd -m dav.pw joe@schmo.com.

Reconfiguring Apache to Support WebDAV. Open a Terminal window, and switch to root access: sudo su. Then navigate to the folder with Apache’s configuration file: cd /etc/httpd. First, let’s make a backup copy of the config file in case something goes wrong: cp httpd.conf httpd.conf.dav.save. Now let’s carefully edit the config file: pico httpd.conf. Uncomment the headers_module line by searching for headers (Ctrl-W, headers, enter) and then pressing Ctrl-D while positioned over the # sign at the beginning of the line. Now search for mod_headers (Ctrl-W, mod_headers, enter) and uncomment that line (Ctrl-D while positioned over beginning # sign). Now search for dav_module (Ctrl-W, dav_module, enter) and uncomment the line (Ctrl-D while positioned over beginning # sign). Now search for mod_dav (Ctrl-W, mod_dav, enter) and uncomment the line (Ctrl-D while positioned over beginning # sign). Now press Ctrl-V repeatedly until you get to the bottom of the file. Switch to your web browser and download this WebDav snippet. When the code snippet displays in your web browser, press Command-A then Command-C to copy all of the code to your clipboard. Then switch back to Pico, click at the bottom of the config file, and paste the code snippet into the config file by pressing Command-V. Use the down arrow to move to the BrowserMatch section of the code we just pasted and be sure “redirect-carefully” didn’t end up on a line by itself. If it did, position the cursor over the first letter “r” and press the backspace key to move it back up to the end of the previous line of code. Don’t worry if a dollar sign displays at the end of the line after you move it. This just indicates that additional text is off the screen… the price we pay for using a free editor. Now we should be all set. Save the config file: Ctrl-X, Y, enter. And restart Apache by deselecting and then reselecting Personal Web Sharing from System Preferences->Sharing. Close the Terminal window by typing exit, pressing enter, and then pressing Command-Q.

Testing Your WebDAV Server. To test whether WebDAV is working, switch to your Desktop and, using Finder, press Command-K. When prompted for the server address, type http://localhost/dav and then click the Connect button. Enter your username and password that you created in the dav.pw password file, and a blank dav folder should appear on your Desktop. Drag a file from your Desktop to the folder to be sure everything is working as it should. If you’ve enabled web access through your Mac and router firewalls (which we have previously covered here), then you should be able to access your WebDAV folder from the Internet with your IP address or domain name using the syntax: http://mydomain.com/dav. Enjoy your new WebDAV server. Now all you need is a friend to share it with.