si14 / nagios_erlang

Nagios plugins for monitoring Erlang process groups/applications/nodes/etc

README

This repository contains scripts to facilitate monitoring Erlang. systems using the Nagios monitoring framework.

At this time it supports monitoring nodes, applications and process groups.

Files

• README - this file
• Makefile - build script
• check_erlang_application.sh - shell script interface to check erlang apps are running
• check_erlang_node.sh - shell script interface to check erlang node is running
• check_erlang_pg.sh - shell script interface to check process group is running
• nagios_erlang.erl - Erlang implementation of checking apps/nodes/pgs
• ebin/ - contains compiled Erlang files

Command Line Usage Examples

Examples of running the verification scripts directly (not via Nagios). These scripts are all being run in a Git checkout of the code, and after running make within that directory.

To run in other directorys, the --beam parameter will need to be updated to point to the directory where nagios_erlang.beam can be found.

Checking Nodes

bash-3.2$ ./check_erlang_node.sh -e /usr/bin/erl -n my_node
OK - Node my_node running.

Checking Applications

bash-3.2$ ./check_erlang_application.sh -e /usr/bin/erl -n my_node -a application
OK - Application application running at my_node.

Checking Process Groups

./check_erlang_pg.sh -e /usr/bin/erl -n my_node -p my_group -w 1
OK - Process group my_group populated on Node my_node with 3 processes.

Full Example

First, we check that the node doesn't exist before we start it:

bash-3.2$ ./check_erlang_node.sh -e erl -n my_node@`hostname` -c cookie
CRITICAL - Node '[e-mail]' not running.

Next, actually start the node:

will-larsons-macbook:~ lethain$ erl -setcookie cookie -name my_node@`hostname`
Erlang R13B03 (erts-5.7.4) [source] [smp:2:2] [rq:2] [async-threads:0] [hipe] [kernel-poll:false]
Eshell V5.7.4  (abort with ^G)
([e-mail])1> node().
'[e-mail]'

And we can verify the node is accessible:

bash-3.2$ ./check_erlang_node.sh -e erl -n my_node@`hostname` -c cookie
OK - Node '[e-mail]' running.

Next we can check for started applications (note that kernel2 is a made up application which doesn't exist, while kernel is a real application which is indeed running):

bash-3.2$ ./check_erlang_application.sh -e erl -c cookie -n my_node@`hostname` -a kernel2
CRITICAL - Application kernel2 not running on Node '[e-mail]'.
bash-3.2$ ./check_erlang_application.sh -e erl -c cookie -n my_node@`hostname` -a kernel
OK - Application kernel running on Node '[e-mail]'.

Last, we can check on the process groups:

And that is all there is to it.