Collectd is a daemon which collects system performance statistics periodically and provides mechanisms to store the values in a variety of ways. Collectd gathers statistics about the system it is running on and stores this information. Those statistics can then be used to find current performance bottlenecks (i.e. performance analysis) and predict future system load (i.e. capacity planning)
You can’t run collectd directly on the Ironport so we needed to find some other way to pull useful data from Ironport. We could either use SNMP (less data) or some other way (more data). After some searching we found out you can also access your Ironport statistics using the web frontend. A logic choice was to use the cURL-XML plugin.
Another important functionality in our setup is the use of graphite, a tool that provides realtime scalable graphing. You can send your metric to graphite in stead of using a local RRD file. This is done via the AMQP plugin for which we provide packages at our yum repository.
You can access the ironport XML file containing more statistics manually: https:///xml/status?, which will result in:
<status build=”rls” hostname=”hostname” timestamp=”20130429193603″>
I’m only going to cover the gauges in this post, because those seem the most relevant.
<gauges>
<gauge name=”ram_utilization” current=”18″ />
</gauge>
You can pull data from this XML using XPath, it takes some time until you find the correct syntax to pull the data, so here is a small example:
<LoadPlugin curl_xml>
Interval 10
<LoadPlugin><Plugin “curl_xml”>
<URL “https://ironport.fqdn/xml/status”>
Host “ironport.fqdn”
Instance “ironport”
User “username”
Password “password”
VerifyPeer false
VerifyHost false
CACert “/etc/pki/tls/certs/ca-bundle.crt”<xpath “/status/gauges/gauge[@name=\”ram_utilization\”]”>
Type “ram_utilization”
ValuesFrom “@current”
</xpath>
</URL>
</Plugin>
That’s about everything you need to do. Remember, if you want your data to be stored in graphite, you also have to configure the AMQP plugin. There are some fine blogposts about that matter, so I’m not going to duplicate this information. Check: Collectd to graphite.