How do I allow a user to use their own domain name for a hosted service?

Question

I am working on an ASP.NET MVC web app that allows people to publish content, but other than publish the content to a remote server, I want to allow people to use their domain name directly. For example, the user "Tom" can have his domain name TomSite.com point to http://www.mywebapp.com/user/tom, but the sub path will also be mapped. For example, TomSite.com/path will be mapped to www.mywebapp.com/user/tom/path, and this is transparent to the web visitor. The visitor will never see "mywebapp.com" anywhere on TomSite.com.

I think Smugmug.com provides such service, to allow people to use their own domain name for the photo portfolio. I want to achieve the same result.

How can I do this? Thanks!

Answer 1

Just make a new record in your webserver setting tomsite.com directly to your mywebapp.com/user/tom/ path ?

See it like an alias :)

Ofcourse, since you're asp.net/windows based, i think you'll have to digg deep into IIS to automate this kind of stuff. If you were on apache it would be adding 3 simple lines to httpd.conf.

Answer 2

Smugmug (who you mentioned) get their users to setup a CNAME record that will alias the url for the user's personal photo section. For most users this will probably require them contacting their host or looking up help files in order to get it all setup.

So, while www.tomsite.com could transparently serve up pages hosted at www.mywebapp.com the users will have to put some kind of effort in. To make it a completely seamless you will need some kind of arrangement with the users web host (Smugmug appear to have such an arrangement with GoDaddy).

I doubt you will be able to setup such integration with all the web hosts out there, so the only complete solution would be to host the websites of your users yourself (I do not know enough about your wider situation to determine if that is a reasonable solution).

Note: setting up an alias on your own web server (aka url rewriting) will not work, unless you host their site yourself, as obviously people fetching from your user's domain will not arrive at your server in the first place.

Answer 3

Have each customer's friendlyname pointed at the external ip address of your webserver.

Use IIS to resolve the friendlyname specified in the host header request to the logical website you want delivered to that friendlyname. IIS will happily map both a website and a virtual folder to the same folder in the file system. Create a website for each customer. Then bind that website to the customer's friendlyname.

Remember to map the default website only to your own friendlyname(s). If you leave it in promiscuous mode (mapped to "*") results will be unpredictable.

To set host header mapping

Select Default Web Site under the Sites node. In the Actions pane at top right click on Bindings... to open the Site Bindings dialog. There will be a list of bindings, probably containing a single entry that says http * 80. Select this and click the Edit... button. Set Host name to your own friendlyname.

Run IIS7 Manager and for each customer site create a website under the Sites node. Set both file path and host header binding while you are creating each web site. Obviously the host header binding (host name) should be that customer's friendlyname.

Answer 4

This require multiple steps.

First you have to find out how your users will configure their domain to have a CNAME record for you site. You can archieve this in a number of ways where the best is education. Making partnerships with hosting providers requires a great deal of volume.

In IIS this will require you to either add each host name manually (however this could also be archieved through scripting) or have a dedicated IP address only for you site.

There is also a need for the domain to be associated with an account. The user has to add this themselves and you would probably add a check in the interface which confirms the domain is pointed at your server. The code for this would look like (remember to include the System.Net namespace).

if (Dns.GetHostEntry("www.user.example.com").HostName == "www.example.com")
{
    // www.user.example.com is a CNAME for www.example.com
}

In you ASP.NET MVC project you need to implement routes for this particular purpose. Create a custom class inheriting from Route which also takes the domain into account.