OpenNMSAt our first tech night last week, Magued one of our uber volunteers who is responsible for maintaining our Cisco firewalls and switches, lobbied us to get a network management platform up and running. Magued had lobbied for quite some time that we must get some kind of monitoring system up so that we weren’t blind as to what was happening on the network.

We had toyed with OpenNMS a few times but never put the full effort into launching it, so on Wednesday we pulled out a box and set it up for production use. Here is an overview on the install:

  • Hardware: Sony Vaio PCV-RS420 P4 2.8, 1 GB RAM, 2-120 GB Software RAID 1.
  • Operating System: CentOS-4.3.
    • Configure for the software mirror
    • Choose server/minimal install.
    • Assign static IP address.
    • Disable the firewall and SELinux.
  • Log in via SSH or the terminal and start yum update to get the latest operating system and package updates.
  • Install Webmin. Use the System -> Software Packages module to install new RPM packages.
  • Follow the OpenNMS Installation Guide with a few things to watch our for…
    • In section 3.3 note where the following variables are pointing to.
      • $OPENNMS_HOME = /opt/OpenNMS
      • $CATALINA_HOME = /var/tomcat4
  • Edit the /opt/OpenNMS/etc/discovery-configuration.xml file so that it reflects the right subnets. It takes about 8 seconds to scan an IP address, so expect it ti take a while to discover all your hosts if you have a large network.
  • Edit /opt/OpenNMS/etc/javamail-configuration.properties file to reflect the correct system sender account for notification emails.
    • Uncomment org.opennms.core.utils.fromAddress=root@[127.0.0.1] and change the email address.
  • Start up and begin to configure OpenNMS.
  • Hint: Don’t turn on your notification status until you have configured notifications or else be prepared for a flood of emails.

After a few hours of discovery, all of our firewalls, managed switches and servers started showing up. After tech nights last night Magued helped us configure SNMP on our backbone switch and our main active directory server. SNMP is pretty cool, once configured right, OpenNMS “discovers” all the services and interfaces a device is running.

We got a good start on the network management system by getting it up and running, but the key is going to be in the configuration. We still have to get SNMP configured for all our firewalls and the rest of our servers. Once all our devices are configured correctly, we have to setup and tweak notifications. An added bonus to OpenNMS is that it does basic Asset Management. We have been looking for an asset management solution for a while but nothing jumped out at us, so I think we will start with this one for now. The nice thing with the integrated asset management will be that when we have an outage we can see exactly where/what the equipment is.

We have had OpenNMS up, running and minimally configured for two days now, it already caught a minor outage when our senior priest’s Internet connection went down at home. When the outage happened we realized the need for a way to correlate events so that when a connection that has equipment running on it goes down, we only get notified that the connection is down and not all the additional notifications for the rest of the equipment. It look like this will be released in an upcoming version, according to the OpenNMS Road Map.