Nagios Remote plugin Executor (NRPE) plugin version 4

Example scenario

In this example scenario, the host segot01 has two services that use the check_nrpe plugin:

• Total processes uses the check_nrpe check command with command argument check_total_procs. The check_nrpe check command preconfigured in OP5 Monitor uses the plugin of the same name. Example output from Test this check:

_USER1_/check_nrpe -s -H 10.0.0.81 -c check_total_procs
Result code: OK
PROCS OK: 80 processes | procs=80;150;200;0;

• Logged in users uses the check_nrpe_users check command, which is implicitly configured to pass the command check_users to the check_nrpe plugin. Example output from Test this check:

_USER1_/check_nrpe -s -H 10.0.0.81 -c check_users
Result code: OK
USERS OK - 1 users currently logged in |users=1;5;10;0

Both services use a check command configured with the -s option to run check_nrpe, which forces an SSL connection for version 2 of the plugin. In version 4 of the plugin, the -s option has a different function and can be removed.

Create a check command

In this example scenario, you will create a new check command that uses the new check_nrpe4 plugin.

1. In OP5 Monitor, go to Manage > Configure.
2. In the Configuration page, click Commands.
3. Under Create new command:
   1. In the command_name field, enter check_nrpe4.
   2. In the command_line field, enter $USER1$/check_nrpe4 -H $HOSTADDRESS$ -c $ARG1$.
4. Click Submit.
5. On the top-right corner, click Save.
6. In the Save configuration page, click Save my changes.

Success: The new check_nrpe4 check command can now be used for existing implementations.

Edit the total processes service

In this example, you will edit the Total processes service to use the new check_nrpe4 check command you have created:

1. In the Services List view, look for Total processes and click Configure this service under Actions.
2. Under Edit service:
   1. In the check_command field, update the value from check_nrpe to check_nrpe4.
   2. Click Test this check the verify that the new check command works:

   _USER_/check_nrpe4 -H 10.0.0.81 -c check_total_procs
   Result code: OK
   PROCS OK: 80 processes | procs=80;150;200;0;

3. Click Submit.
4. On the top-right corner, click Save.
5. In the Save configuration page, click Save my changes.

Success: The Total processes service now uses the new check_nrpe4 check command.

Edit the logged in users service

In this example, you will edit the Logged in users service to use the new check_nrpe4 check command you have created:

Note: This example applies for other services that use the check_nrpe_xyz check commands. For example, check_nrpe_load, check_nrpe_swap, and so on.

1. In the Services List view, look for Logged in users and click Configure this service under Actions.
2. Under Edit service:
   1. In the check_command row, click Syntax help to display the command line of the selected check command:

   Command line of selected check command:
   $USER1$/check_nrpe -s -H $HOSTADDRESS$ -c check_users

   2. Copy the arguments after the -c option from the command line. In this example, it is check_users.
   3. In the check_command field, update the value to check_nrpe4.
   4. In the check_command_args field, paste the argument you copied. In this example, it is check_users.
   5. Click Test this check the verify that the new check command works:

   _USER1_/check_nrpe4 -H 10.0.0.81 -c check_users
   Result code: OK
   USERS OK - 1 users currently logged in |users=1;5;10;0

3. Click Submit.
4. On the top-right corner, click Save.
5. In the Save configuration page, click Save my changes.

Success: The Logged in users service now uses the new check_nrpe4 check command.

Before you begin

When you change a check command to use a new plugin, all services using that check command are affected.

To see which services use a particular check command, use the OP5 Monitor UI to perform a filter query on your browser address bar.

For example, the following query filters out services that use the check_nrpe_users check command:

https://HOST/monitor/index.php/listview/?q=%5Bservices%5D%20check_command%20%3D%20%22check_nrpe_users%22

Edit the check command

In this example, you will update the check command check_nrpe_users to use the new check_nrpe4 plugin:

Note: This example applies for other services that use the check_nrpe_xyz check commands. For example, check_nrpe_load, check_nrpe_swap, and so on.

1. In OP5 Monitor, go to Manage > Configure.
2. In the Configuration page, click Commands.
3. Under Command to edit, select check_nrpe_users and click Go.
4. Under Edit command, update the command_line field value.
   • Old value: $USER1$/check_nrpe -s -H $HOSTADDRESS$ -c check_users
   • New value: $USER1$/check_nrpe4 -H $HOSTADDRESS$ -c check_users
5. Click Submit.
6. On the top-right corner, click Save.
7. In the Save configuration page, click Save my changes.

Success: The check_nrpe_users check command now uses the new check_nrpe4 plugin.