# Multiple virtual host? **URL:** \ **Category:** Rails\ **Created:** [April 2, 2007, 5:39pm UTC](https://www.ruby-forum.com/t/multiple-virtual-host/90874 "2007-04-02T17:39:19Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![dankitania](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/e9a140/32.png) [@dankitania](https://www.ruby-forum.com/u/dankitania)\ **Post date:** [April 2, 2007, 5:39pm UTC](https://www.ruby-forum.com/t/multiple-virtual-host/90874/1 "2007-04-02T17:39:19Z")
I am trying to serve up two applications from one box. (It’s not a commercial system; it’s just a box on my desktop, that I’m using to test out RoR.) SETUP. In my httpd.conf, I’ve got something like \ ServerName URL ServerAlias URL ServerAdmin USER@PLACE ProxyPass /APP [http://127.0.0.1:8000/APP](http://127.0.0.1:8000/APP) ProxyPassReverse /APP [http://127.0.0.1:8000/APP](http://127.0.0.1:8000/APP) ProxyPass /images [http://127.0.0.1:8000/APP/images](http://127.0.0.1:8000/APP/images) \ ServerName URL ServerAlias URL ServerAdmin USER@PLACE ProxyPass /NEWAPP [http://127.0.0.1:8010/NEWAPP](http://127.0.0.1:8010/NEWAPP) ProxyPassReverse /NEWAPP [http://127.0.0.1:8010/NEWAPP](http://127.0.0.1:8010/NEWAPP) ProxyPass /images [http://127.0.0.1:8010/NEWAPP/images](http://127.0.0.1:8010/NEWAPP/images) where URL is for my machine, and APP and NEWAPP are the names of two applications, which I serve up with mongrel\_rails start -d -p 8000 -a 127.0.0.1 -e development --prefix /APP mongrel\_rails start -d -p 8010 -a 127.0.0.1 -e development --prefix /NEWAPP THE PROBLEM. Only one site works. (The problem is in the setup, not the site code, because I can make _either_ one work by commenting out parts of my httpd.conf file.) Q: how should I set up httpd.conf (or mongrel\_rails) to serve two applications from one box? ---
**Author:** ![dankitania](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/e9a140/32.png) [@dankitania](https://www.ruby-forum.com/u/dankitania)\ **Post date:** [April 2, 2007, 8:56pm UTC](https://www.ruby-forum.com/t/multiple-virtual-host/90874/2 "2007-04-02T20:56:11Z")
The ServerName (and ServerAlias) need to be different for the two different virtual hosts. It’s not enough to just proxy them to different internal URLs. b ---
**Author:** ![dankitania](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/e9a140/32.png) [@dankitania](https://www.ruby-forum.com/u/dankitania)\ **Post date:** [April 3, 2007, 1:26am UTC](https://www.ruby-forum.com/t/multiple-virtual-host/90874/3 "2007-04-03T01:26:19Z")
Interesting. But the URL (“[my.computer.com](http://my.computer.com)”, in the examples below) is determined by my system adminstrator and someone who set up a DNS table, isn’t it? I’m confused; the examples I’ve seen suggest that I can just invent new URLs, but I don’t see how that can work. Or is the idea to put something after the “/” in a URL, e.g. to name the two sites [my.computer.com/a/APP](http://my.computer.com/a/APP) for APP, and [my.computer.com/b/NEWAPP](http://my.computer.com/b/NEWAPP) for NEWAPP? (And, should I therefore be calling mongrel\_rails differently?) I’m sorry I’m being so dense on this. I’m only following up, continuing to be a pest, because I think others might be interested. D ---
**Author:** ![dankitania](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/e9a140/32.png) [@dankitania](https://www.ruby-forum.com/u/dankitania)\ **Post date:** [April 3, 2007, 2:03am UTC](https://www.ruby-forum.com/t/multiple-virtual-host/90874/4 "2007-04-03T02:03:09Z")
Given this, I wonder how one can host more than one RoR site on a given box, without changing any DNS tables on a higher-up box. At least from my limited academic perspective, this is an important facet of a web scheme. I have many little websites on my box, e.g. one for each course I teach, one for each multi-author paper I write, one for each multi-PI proposal I write, etc. (I wonder whether the web would have spread, in its early academic days, if things weren’t so easy.) ---
**Author:** ![dankitania](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/e9a140/32.png) [@dankitania](https://www.ruby-forum.com/u/dankitania)\ **Post date:** [April 3, 2007, 3:03am UTC](https://www.ruby-forum.com/t/multiple-virtual-host/90874/5 "2007-04-03T03:03:45Z")
If you don’t want to get another domain name, you may ask other people to update their hosts file (/etc/hosts), or you may serve each websites on different port. The idea of virtual host is that requests are forwarded according to the domain name of the request. So that [www.abc.com](http://www.abc.com) and [www.def.com](http://www.def.com) will be served differently even though the ip address is the same. Alternatively, you may obtain multiple IP addresses and bind each site to it if you are only serving in local area network. ---
**Author:** ![dankitania](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/e9a140/32.png) [@dankitania](https://www.ruby-forum.com/u/dankitania)\ **Post date:** [April 3, 2007, 3:00pm UTC](https://www.ruby-forum.com/t/multiple-virtual-host/90874/6 "2007-04-03T15:00:11Z")
My summary so far, for anyone catching this thread with a search: PHP: users with no special privileges can create dozens of sites using the (HOST)/~(USER)/(SITENAME) scheme. This is done without restarting the web server, and without editing (and thus potentially damaging) configuration files. RoR: some special magic is required. (I’m not sure what, yet.) Thus PHP is analagous to HTML, in the sense that ease of use is likely to create a wide community of experts. I hope that RoR (and Django and the like) can build up such a community somehow. ---
**Author:** ![dankitania](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/e9a140/32.png) [@dankitania](https://www.ruby-forum.com/u/dankitania)\ **Post date:** [April 3, 2007, 3:22pm UTC](https://www.ruby-forum.com/t/multiple-virtual-host/90874/7 "2007-04-03T15:22:39Z")
Hi Dan, I believe you have got the wrong idea about virtual host, virtual host is for domain name mapping, not subdirectory. You can do this in rail with by updating the route.rb to override the default routing rule, or with restful. I believe restful is the way to go for the (HOST)/~(USER)/(SITE) scenario. You can also create a controller for each user if each user request is handled differently. ---
**Author:** ![dankitania](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/e9a140/32.png) [@dankitania](https://www.ruby-forum.com/u/dankitania)\ **Post date:** [April 3, 2007, 1:51am UTC](https://www.ruby-forum.com/t/multiple-virtual-host/90874/8 "2007-04-03T01:51:02Z")
You can’t just make up URLs and expect them to work on the open web… that’s what DNS is for. For using strictly on your local machine, you can make up host names and put them in your hosts file (/etc/hosts on \*nix, google for it on windows). b ---
**Author:** ![dankitania](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/e9a140/32.png) [@dankitania](https://www.ruby-forum.com/u/dankitania)\ **Post date:** [April 3, 2007, 9:21pm UTC](https://www.ruby-forum.com/t/multiple-virtual-host/90874/9 "2007-04-03T21:21:59Z")
I don’t think this has anything to do with Rails. You would have the same problem if you were using PHP. This boils down to a mis- understanding of the purpose of the VirtualHost directive in Apache. The way virtual hosts work is to match against the Host header in the HTTP request (basically the client connects to the server using the server’s IP but also provides the hostname it was initially asked to connect to). So if i set up my DNS zones so that [www.blah.com](http://www.blah.com) and [www2.blah.com](http://www2.blah.com) both resolve to the same IP my browser will provide which of the 2 I asked for to the server when connecting. Apache then uses this information to determine which VirtualHost directive to use to process the request. The path that is being requested (the / blah.html in [www.blah.com/blah.html](http://www.blah.com/blah.html)) is part of the actual request, not the HTTP headers and thus not available to Apache at the time when it needs to make its vhost decision. If you want to do path based determination of settings you need to use a directive _within_ your VirtualHost directive that set up the proxy settings you wish to use for each location. Have a look at [core - Apache HTTP Server Version 2.2](http://httpd.apache.org/docs/2.2/mod/core.html#location) for more information (assuming Apache 2.2…similar sections are available for other version of the Apache server/documentation). Best of luck! ~Ross On Apr 3, 9:00 am, Dan K. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) ---
**Author:** ![dankitania](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/e9a140/32.png) [@dankitania](https://www.ruby-forum.com/u/dankitania)\ **Post date:** [April 3, 2007, 10:48pm UTC](https://www.ruby-forum.com/t/multiple-virtual-host/90874/10 "2007-04-03T22:48:16Z")
The only reason “(HOST)/~(USER)/(SITENAME)” works for you is because the sysadmin of your server configured apache to map ~username to a directory in your home directory. The php then works in this scenario because it is just template files, html with php code which mod\_php runs and replaces. Rails does not work on this principle. It is for building complete, well-architected web applications. The template files (the html with ruby embedded) are not publicly accessible because Rails processes the file for us and writes the final output into the http socket output stream. That probably sounds overly academic, but there are very good reasons why it is designed that way. Basically, if you just want to embed some code into an html file, stick with php. b PS: Oh, with correct configuration of apache, you can use the ~user stuff with rails as well. However, you’d need edit access to the apache config and you’d need to know what you are doing. ---
**Author:** ![dankitania](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/e9a140/32.png) [@dankitania](https://www.ruby-forum.com/u/dankitania)\ **Post date:** [April 3, 2007, 11:40pm UTC](https://www.ruby-forum.com/t/multiple-virtual-host/90874/11 "2007-04-03T23:40:03Z")
> If you want to do path based > determination of settings you need to use a directive > _within_ your VirtualHost directive Thanks, Ross, I’ll check into that. I’ve been trying to deploy my app for months now. (A search on this forum would illustrate the kindness of strangers who have helped me in this, and my very slow understanding of the advice offered.) Luckily, my app is mainly an experiment to see whether RoR will prove useful for me, so I have the luxury of revisiting the problem in the evenings or on weekends. I’ve found that the ratio of (effort in learning RoR) to (effort in deploying RoR) to be unexpectedly high. It’s a bit of a shame that this ratio is so seldom mentioned in the tutorials that (reasonably) sing the praises of RoR. Oh well, I enjoyed reading the Agile book on RoR, so I guess I’ll buy the book on deploying RoR as well … even though, in the end, I expect I’ll just be copying ten lines from the book into my httpd.conf file.