ethMon

ethMon is an Icinga2/Nagios compatible Python plugin for network traffic monitoring on a specific interface. Currently the carbon/graphite data is always in bytes.

Graph drawn from a collected data

In order to calculate the speed the plugin keeps the data from previous runs in ~/.ethMonCache.db

Installation

Download ethMon to the Icinga/Nagios plugin directory (/usr/lib/nagios/plugins/ on Debian 10)
- Link
Ensure that the executable bit of ethMon is set

Configuration

In order to use the plugin with Icinga the following configuration is needed:

in /usr/share/icinga2/include/command-plugins.conf add the following

template CheckCommand "ethMon-common" {
    command = [ PluginDir + "/ethMon" ]
    arguments = {
            "-i" = {
                value = "$interface$"
                description = "Interface which will be monitored"
            }
            "-w" = {
                value = "$speed_warn$"
                description = "Warning threshold"
            }
            "-c" = {
                value = "$speed_crit$"
                description = "Critical threshold"
            }
            "-s" = {
                value = "$speed_scale$"
                description = "Speed scaling"
            }
            "--interval" = {
                value = "$chk_interval$"
                description = "Interval between the checks (in seconds)"
            }
    }
    vars.speed_warn = 60
    vars.speed_crit = 100
    vars.speed_scale = "Mb"
    vars.chk_interval = 30
}
object CheckCommand "ethMon" {
    import "ethMon-common"
}

then per host (or zone if the interface name match everywhere):

apply Service "Traffic-enp3s5" {
    check_command = "ethMon"
    check_interval = 30
    vars.interface = "enp3s5"
command_endpoint = host.vars.client_endpoint // Check executed on client node
assign where host.vars.client_endpoint == "TheMonitoredHost" // The service is applied only to this node
}

NOTE: The same value must be used for check_interval & vars.chk_interval

Support for threshold ranges

Icinga threshold ranges documentation

The plugin has partial support for the ranges described in the Icinga documentation. If used the ranges must be specified for both (warning & critical) parameters.

Implemented are the following specifications:

min:max - The value must be outside the range in order the alert to be triggered
@min:max - The value must be inside the range in order the alert to be triggered
min: - The value must be below min or above 10*10^256 in order the alert to be triggered
@min: - The value must be between min and 10*10^256 in order the alert to be triggered
:max - The value must be below 0 and max in order the alert to be triggered
@:max - The value must be between 0 and max in order the alert to be triggered

Motivation

The plugin has been created as check_eth from Nagios Exchange refused to work in my current setup.

githubDante/ethMon

ethMon

Installation

Configuration

Motivation