Using ntpstat to check NTPD status with Zabbix

The standard way of checking a service in Zabbix checks that the service is running, but I wanted to know not only that the NTPD service was running but that the time was synchronized.  ntpstat is a great utility that does both, checks that the ntpd service is running and then tells you whether the server is synchronized.   ntpstat will report the synchronization state of the NTP daemon running on the local machine.  ntpstat returns 0 if clock is synchronized.  ntpstat returns 1 if clock is  not  synchronized.  ntpstat returns 2 if clock state is unknown, for example if ntpd can’t be contacted.

I created a Zabbix item to use ntpstat.  Here are the 2 ways I have used this new check:

The first way to use ntpstat with Zabbix is to simply create an item using the system.run function.

Name - ntpstat status
Type - Zabbix agent (active)
Key  - system.run[ntpstat &> /dev/null ; echo $?]
Type of Information - Text

Ensure EnableRemoteCommands=1 is set in your zabbix_agentd.conf file for this to work.

The second way to create the item is to use custom user parameters.  This requires a file modification on the monitored instance, so if you have a lot of instances to monitor or do not have a good way to automate this file modification, you may want to stick with option 1

I like creating new userparameter files for custom parameters.

/etc/zabbix/zabbix_agend.d/userparameter_custom_linux.conf
UserParameter=custom.net.ntpstat,ntpstat &> /dev/null ; echo $?

Then create an item similar to above but with a change to the key

Name - ntpstat status
Type - Zabbix agent (active)
Key  - custom.net.ntpstat
Type of Information - Numeric (unsigned)
Data Type - Decimal

Once your custom userparameter file is placed you’ll need to restart the zabbix agent. The last step with either item creation option is to create a trigger that alerts when the returned value is not 0.

I like this check much better than my original one that just alerted when the ntpd service was down.  Now I get alerted before time synchronization issues become an issue for the applications.

This was tested on both CentOS 6.7 and CentOS 7.1, but this should work on your Linux distro of choice as long as you have ntpstat installed.

Hope this helps

 

 


Device eth0 is not present after cloning RHEL/CentOS in VMWare

#ifup eth0
Device eth0 does not seem to be present, delaying initialisation

Easy fix:

Remove the networking interface rules file, it will be regenerated

# rm -f /etc/udev/rules.d/70-persistent-net.rules

Update your interface configuration file

# vim /etc/sysconfig/networking/devices/ifcfg-eth0

Remove the MACADDR and  the UUID entries

Save and exit the file

Restart the networking service

# service network restart