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diff --git a/site/src/docs/mongrel_cluster.page b/site/src/docs/mongrel_cluster.page deleted file mode 100644 index 4893206..0000000 --- a/site/src/docs/mongrel_cluster.page +++ /dev/null @@ -1,138 +0,0 @@ ---- -title: mongrel_cluster -inMenu: true -directoryName: mongrel_cluster ---- - -h1. Using Mongrel Cluster<br> -<small><small>by Austin Godber</small></small> - -"Mongrel_cluster":http://rubyforge.org/projects/railsmachine/ is a -"GemPlugin":http://mongrel.rubyforge.org/gem_plugin_rdoc that wrappers -the mongrel HTTP server and simplifies the deployment of webapps -using a cluster of mongrel servers. Mongrel_cluster will conveniently configure -and control several mongrel servers, or groups of mongrel servers, which are -then load balanced using a reverse proxy solution. Typical load balancing -reverse proxies include: -* "Apache":apache.html - flexible and complex -* "Lighttpd":lighttpd.html - development has stalled -* "Pound":pound.html - Simple and SSL capable -* "Pen/Balance":pen_balance.html - Simple - -h2. Requirements - -Throughout these instructions we will assume the following: -* All mongrel instances are running on the same machine -* Mongrel *0.3.13* or greater -* "Mongrel_cluster":http://rubyforge.org/projects/railsmachine/ *0.2.0* or greater -* Linux platform (Centos 4.3 in this case, so you will see RedHat like commands). -* You have *sudo* or *root* access - -h2. Preliminary steps - -In general, when deploying a mongrel cluster, none of the mongrel servers will -be listening on a privileged port. This is nice, we don't have to run mongrel as -root, therefore we should create a user for mongrel to run as: -<pre><code> - $ sudo /usr/sbin/adduser -r mongrel -</code></pre> -For the purpose of this example we will just use a freshly minted rails app. -You can adjust these instructions to work with your app, wherever you may have -placed it but lets pretend we are working in */var/www/apps*. So lets go set -up our app and test that mongrel will serve it: -<pre><code> - $ cd /var/www/apps - $ rails testapp - $ cd testapp - $ mongrel_rails start -</code></pre> -You should now be able to see your application at @http://host:3000/@. If you -can, you are good to go. Hit @CTRL+C@ to stop the mongrel server. At a minimum -the log directory of your app has to be writable by the *mongrel* user: -<pre><code> - $ sudo chown -R mongrel:mongrel /var/www/apps/testapp -</code></pre> - -h2. Mongrel Cluster Setup - -With mongrel working and our webapp directory prepared we can proceed with the -mongrel_cluster configuration step: -<pre><code> - $ sudo mongrel_rails cluster::configure -e production \ - -p 8000 -N 3 -c /var/www/apps/testapp -a 127.0.0.1 \ - --user mongrel --group mongrel -</code></pre> -This will write a configuration file in *config/mongrel_cluster.yml*. We have -setup to run our cluster in production mode as the user *mongrel* and will start -3 mongrel servers listening on ports 8000, 8001, and 8002. Now, lets do a quick -test of what we have setup so far: -<pre><code> - $ sudo mongrel_rails cluster::start -</code></pre> -Checking our host on ports 8000, 8001, and 8002 we should now be able to see our -test application. We can stop all of those mongrels with -@sudo mongrel_rails cluster::stop@. - -h2. On Boot Initialization Setup - -At this point, mongrel and mongrel_cluster are setup and working with our sample -webapp. Ultimately, we want this cluster to start on boot. Fortunately, -mongrel_cluster comes with an init script that we can just drop into place. All -we need to do is put the configuration files in */etc/mongrel_cluster* and take care of -a few system tasks: -<pre><code> - $ sudo mkdir /etc/mongrel_cluster - $ sudo ln -s /var/www/apps/testapp/config/mongrel_cluster.yml \ - /etc/mongrel_cluster/testapp.yml - $ sudo cp \ - /path/to/mongrel_cluster_gem/resources/mongrel_cluster \ - /etc/init.d/ - $ sudo chmod +x /etc/init.d/mongrel_cluster -</code></pre> -Now we have a typical System V init script that will launch our mongrel cluster. -Actually, this script will launch any cluster that has a configuration file in -*/etc/mongrel_cluster/*. So when we run */etc/init.d/mongrel_cluster start* it -will start all clusters. Likewise for stop and restart. If we are using a -RedHat like system we can configure mongrel_cluster for startup: -<pre><code> - $ sudo /sbin/chkconfig --level 345 mongrel_cluster on -</code></pre> -For users of Debian, you can use this command to install the script: -<pre><code> - $ sudo /usr/sbin/update-rc.d -f mongrel_cluster defaults -</code></pre> -*NOTE* At this point there are a few issues with this init script that only apply -under certain circumstances. Those issues include: - -* *Shebang line* - The init script uses *#!/usr/bin/env ruby* to find the -appropriate interpreter. Some distribution installs of ruby only give you a -/usr/bin/ruby1.8. You may change the shebang line or simply create a symbolic -link from /usr/bin/ruby1.8 to /usr/bin/ruby[3]. -* *mongrel_cluster_ctl location* - If you have installed your gems in -/usr/local/ you may find that the init script can not find mongrel_cluster_ctl. -To resolve this, you can symbolically link /usr/local/bin/mongrel_cluster_ctl into -/usr/bin/ - -h2. Conclusion - -We have configured mongrel and mongrel_cluster with our webapp and setup -mongrel_cluster to run our cluster at startup. What's missing? Well, unless -your application users expect to have to connect to ports 8000-8002 you had best -check out the reverse proxy options listed above. - -The process of setting up mongrel_cluster will be the same for all of the -reverse proxy deployment options. So this document will likely serve as a reference -for several of the other deployment guides. - -<hr> - -fn1. Thanks to "Bradley Taylor":http://fluxura.com/ for writing -mongrel_cluster and recent improvements in its startup capabilities. The -following people have provided valuable feedback on this document: Alison Rowland. - -fn2. @adduser -r@ is a RedHat-centric way of creating a system account. For -Debian-ish distributions replace that with @adduser --system mongrel@. - -fn3. If you have this problem, you will probably discover other ruby related -executables are also missing. You may want to link irb1.8 and ri1.8 as well, -though only /usr/bin/ruby is necessary for this init script. |