title: failed to add munin node to monitoring
body: <p>I'm trying to setup some new hosts in munin for monitoring. For some reason it ain't happening! </p>
  
  <p>Here's what I've tried so far. </p>
  
  <p>On the munin server, which is already monitoring several other hosts, I've added the host I want in /etc/munin/munin.conf</p>
  
  <pre><code>[db1]
      address   10.10.10.25 # &lt;- obscured the real IP address 
      use_node_name yes
  </code></pre>
  
  <p>And on the db1 host I have this set in /etc/munin/munin-node.conf</p>
  
  <pre><code>host_name  db1.example.com
  allow ^127\.0\.0\.1$
  allow ^10\.10\.10\.26$
  allow ^::1$
  port 4949
  </code></pre>
  
  <p>And I made sure to restart the services on both machines.</p>
  
  <p>From the monitoring host I can telnet to the new server I want to monitor on the munin port:</p>
  
  <pre><code>[root@monitor3:~] #telnet db1.example.com 4949
  Trying 10.10.10.26...
  Connected to db1.example.com.
  Escape character is '^]'.
  # munin node at db1.example.com
  </code></pre>
  
  <p>Wait a few minutes.. and nothing! The new server won't appear in the munin dashboard on the munin monitoring host. </p>
  
  <p>In the /var/log/munin/munin-update.log log on the db1 host (the one I'm trying to monitor) I find this:</p>
  
  <pre><code>2015/11/30 03:20:02 [INFO] starting work in 14199 for db1/10.10.10.26:4949.
  
  2015/11/30 03:20:02 [FATAL] Socket read from db1 failed.  Terminating process. at /usr/share/perl5/vendor_perl/Munin/Master/UpdateWorker.pm line 254.
  
  2015/11/30 03:20:02 [ERROR] Munin::Master::UpdateWorker&lt;db1;db1&gt; died with '[FATAL] Socket read from db1 failed.  Terminating process. at /usr/share/perl5/vendor_perl/Munin/Master/UpdateWorker.pm line 254.
  </code></pre>
  
  <p>What could be going on here? And how can I solve this ?</p>