Monitor ping connectivity

You can monitor ping connectivity from your own server to any other server that interests you. The server just needs to be contactable through ping by the server that will monitor it, thus it allows the server to be inside an internal network without access to the internet - useful to check up VPN links for example. 

In this post we will monitor ping uptime of server 46.4.170.139

On a server that is being monitored by mist.io, edit collectd.conf (/opt/mistio-collectd/collectd.conf ) and add the ip address on the Plugin ping section, eg

LoadPlugin ping
<Plugin ping>
	Host "8.8.8.8"
	Host "46.4.170.139"
</Plugin>

Now restart collectd

root@monitor:~# /opt/mistio-collectd/collectd.sh restart
Stopping mist.io collectd
Starting mist.io collectd

Select the machine on mist.io, click on 'Add graph', then ping, then select the ip of the machine. The graphs of the ping connectivity will appear in a few seconds

You can also monitor the droprate and get notified when it is too high. 

Again, add graph, and this time we select ping droprate and our ip address

the ping droprate diagram will appear. We can now set a rule (by clicking on 'add rule') to get alerted if ping droprate is bigger than 0 (which means packets are getting lost, and either the server is down, or there is some sort of network issue) for every value within 1 minutes. These all can be adjusted, so that we minify false positive alerts, and be notified when there is a real problem