Posts Tagged ‘nagios’

check_snmp_extend is a python script that I found orphaned on some Nagios forum. It facilitates using snmpd as an agent for executing Nagios plugin scripts. I adopted it made a few changes and tossed it on github a while back. I’m happy to merge initial snmp v3 support from Lee Whalen

No one likes to forget to renew a domain. Its not wholly uncommon though. Microsoft forgot to renew passport.com in 1999, and hotmail.co.uk in 2003. Vivendi Universal forgot to renew its MP3.com in 2003, the Washington Post forgot to renew in 2004, and Foursquare forgot to renew their domain in 2010.

I stumbled on the check_domain nagios plugin this weekend so I figured I would make some quick modifications and roll it into a Zenpack. You can find ZenPacks.community.CheckDomain on my github page. It has a really boreing doomsday graph included. Hope someone finds it useful.

I know I’ve mentioned how much I love the sysstat package before. I use sar regularly to help with performance diagnostics (Analyzing Linux System Performance And Finding Bottle Necks, CPU Performance Analysis In Linux, Baseline Analysis Is Important, CPU Performance Analysis In Linux Revisited). I wrote this little Nagios plugin to collect the performance metrics that sar collects.

I use this plugin with Zenoss and I set any performance thresholds there, more important to me was collecting the information for historical graphing. I searched around and didn’t really find any existing solutions thats why anyone wanting to do similar perhaps with cacti is stuck with my craptastic code (or please point me to a better implementation).  Anyway if you want to grab the plugin and check it out its on github.

check_sar_perf

If you hadn’t already guessed I am a big fan of the Xen hypervisor. Lately I have been using the Citrix XenServer release because it makes it quite palatable for my co-workers. One annoyance that I do have about XenServer is the requirement that you license it (with a free license) every year. If you fail to license it the GUI stops working. Now I hate relying on GUIs but the fact of the matter is others in my team expect to have a working GUI when they need to do something. And I dont know about you but I don’t really log onto the management console very often. Really I only log on to it if I need to provision a new server so its entirely plausible that a license would expire and I wouldn’t know about it until I really needed to do something.

I ended up writing a little Nagios plugin that checks the license expiration date using XenAPI. I don’t know that it’s 100% compliant with the plugin specification but it does work for me. I actually don’t prefer to use the warn and critical states with the Nagios (I use the performance data with Zenoss and apply thresholds there. I find that to be a bit more flexible.) but I did implement them. The plugin can be executed on the XenServer (you may want to reference how to install nrpe on XenServer) or on from your monitoring host as long as the host performing the check has the python XenAPI installed.

The plugin check_citrix_xenserver_license can be found on github.

I hope someone can find it useful.

I like to have as little run in dom0 as possible. However some things you really need checked from dom0, like the status of your raid perhaps. Just some quick instructions on getting Nagios NRPE running in XenServer.

1. Install EPEL repository and disable it by default (remember we don’t want to accidentally install unnecessary packages)

   wget http://download.fedora.redhat.com/pub/epel/5/$(uname -i)/epel-release-5-3.noarch.rpm
   rpm -hiv epel-release*.rpm
   sed -i 's/enabled=1/enabled=0/g' /etc/yum.repos.d/epel.repo
   

2. Install nrpe and configure it to start on boot

   yum install --enablerepo=epel nrpe
   chkconfig nrpe on
   

3. Modify the firewall to allow NRPE connections. Add the following before the REJECT line in /etc/sysconfig/iptables

   -A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 5666 -j ACCEPT
   

4. Restart your firewall and start nrpe

   restart your firewall , and start nrpe
   /etc/init.d/iptables restart && /etc/init.d/nrpe start
   

5. Configure nrpe like normal and have fun