title: Why am I getting an Apache Proxy 503 error?
body: <p>My server was doing just fine up until yesterday. It was running <a href="http://www.redmine.org/" rel="noreferrer">Redmine</a>, and it was the happiest little server <strong>until</strong> my "friend" imported a SQL table that my little guy couldn't take. Unfortunately, after an hour of trying to get the lil guy to respond, we had to power cycle him.</p>
  
  <p>Now after restart, we get a 503 error when trying to visit the domain connected to Redmine.  It's hooked up to a <a href="https://rubygems.org/gems/mongrel" rel="noreferrer">Mongrel</a> daemon, and we use Apache Proxy to direct all connections to the port Redmine is running on.</p>
  
  <p>Using Lynx on the server (<code>http://localhost:8000</code>) you can see the Ruby application working fine. But this bit is not working in my Apache configuration file:</p>
  
  <pre><code>&lt;VirtualHost *:80&gt;
      ServerName sub.example.com
      ProxyPass / http://localhost:8000
      ProxyPassReverse / http://localhost:8000
      ProxyPreserveHost on
      LogLevel debug
  &lt;/VirtualHost&gt;
  </code></pre>
  
  <p>Here's the error log output for Apache:</p>
  
  <pre>
  [debug] mod_proxy_http.c(54): proxy: HTTP: canonicalising URL //localhost:8000
  [debug] proxy_util.c(1335): [client 216.27.137.51] proxy: http: found worker http://localhost:8000 for http://localhost:8000/
  [debug] mod_proxy.c(756): Running scheme http handler (attempt 0)
  [debug] mod_proxy_http.c(1687): proxy: HTTP: serving URL http://localhost:8000/
  [debug] proxy_util.c(1755): proxy: HTTP: has acquired connection for (localhost)
  [debug] proxy_util.c(1815): proxy: connecting http://localhost:8000/ to localhost:8000
  [debug] proxy_util.c(1908): proxy: connected / to localhost:8000
  [debug] proxy_util.c(2002): proxy: HTTP: fam 2 socket created to connect to localhost
  
  [error] (13)Permission denied: proxy: HTTP: attempt to connect to 127.0.0.1:8000 (localhost) failed
  [error] ap_proxy_connect_backend disabling worker for (localhost)
  
  [debug] proxy_util.c(1773): proxy: HTTP: has released connection for (localhost)
  </pre>