We use Rittal LCP - Liquid Cooling Package units to chill the 19“ racks and equipment in the datacenters. The LCPs come with their own Rittal CMC-TC units for management and monitoring purposes. With check_rittal_health there is already a Nagios plugin to monitor Rittal CMC-TC units. Unfortunately this plugin didn't cover the LCPs, which come with a plethora of built-in sensors. Also the existing plugin didn't allow to set individual monitoring thresholds. Therefor i modified the existing plugin to accomodate our needs. The modified version can be downloaded here check_rittal_health.pl.

The whole setup for monitoring Rittal CMC-TC and LCP with Nagios looks like this:

1. Configure your CMC-TC unit, see the manual here: CMC-TC Basic CMC DK 7320.111 - Montage, Installation und Bedienung. Essential are the network settings, a user for SNMPv3 access, a SNMP trap receiver (your Nagios server running SNMPTT). Optional, but highly recommended, are the settings for the NTP server, change of the default user passwords and disabling insecure services (Telnet, FTP, HTTP).

2. Download the Nagios plugin check_rittal_health.pl and place it in the plugins directory of your Nagios system, in this example /usr/lib/nagios/plugins/:

   $ mv -i check_rittal_health.pl /usr/lib/nagios/plugins/
   $ chmod 755 /usr/lib/nagios/plugins/check_rittal_health.pl

3. Define the following Nagios commands. In this example this is done in the file /etc/nagios-plugins/config/check_cmc.cfg:

   # check Rittal CMC status
   define command {
       command_name    check_cmc_status
       command_line    $USER1$/check_rittal_health.pl --hostname $HOSTNAME$ --protocol $ARG1$ --username $ARG2$ --authpassword $ARG3$ --customthresholds "$ARG4$"
   }

4. Verify that a generic check command for a running SNMPD is already present in your Nagios configuration. If not add a new check command like this:

   define command {
       command_name    check_snmpdv3
       command_line    $USER1$/check_snmp -H $HOSTADDRESS$ -o .1.3.6.1.2.1.1.3.0 -P 3 -t 30 -L $ARG1$ -U $ARG2$ -A $ARG3$
   }

   Verify that a generic check command for a SSH service is already present in your Nagios configuration. If not add a new check command like this:

   # 'check_ssh' command definition
   define command {
       command_name    check_ssh
       command_line    /usr/lib/nagios/plugins/check_ssh -t 20 '$HOSTADDRESS$'
   }

   Verify that a generic check command for a HTTPS service is already present in your Nagios configuration. If not add a new check command like this:

   # 'check_https_port_uri' command definition
   define command {
       command_name    check_https_port_uri
       command_line    /usr/lib/nagios/plugins/check_http --ssl -I '$HOSTADDRESS$' -p '$ARG1$' -u '$ARG2$'
   }

5. Define a group of services in your Nagios configuration to be checked for each CMC-TC device:

   # check host alive
   define service {
       use                     generic-service-pnp
       hostgroup_name          cmc
       service_description     Check_host_alive
       check_command           check-host-alive
   }
   
   # check sshd
   define service {
       use                     generic-service
       hostgroup_name          cmc
       service_description     Check_SSH
       check_command           check_ssh
   }
   
   # check snmpd
   define service {
       use                     generic-service
       hostgroup_name          cmc
       service_description     Check_SNMPDv3
       check_command           check_snmpdv3!authNoPriv!<user>!<pass>
   }
   
   # check httpd
   define service {
       use                     generic-service-pnp
       hostgroup_name          cmc
       service_description     Check_service_https
       check_command           check_https_port_uri!443!/
   }
   
   # check Rittal CMC status
   define service {
       use                     generic-service-pnp
       servicegroups           snmpchecks
       hostgroup_name          cmc
       service_description     Check_CMC_Status
       check_command           check_cmc_status!3!<user>!<pass>!airTemp,15:32,10:35\;coolingCapacity,0:10000,0:15000\;events,0:1,0:2\;fan,450:2000,400:2500\;temp,15:30,10:35\;waterFlow,0:70,0:100\;waterTemp,10:25,5:30
   }

   Replace generic-service-pnp with your Nagios service template that has performance data processing enabled. Replace <user> and <pass> with the user credentials configured on the CMC-TC devices for SNMPv3 access. Adjust the sensor threshold settings according to your requirements, see the output of check_rittal_health.pl -h for an explaination of the threshold settings format.

6. Define a service dependency to run the check Check_CMC_status only if the Check_SNMPDv3 was run successfully:

   # Rittal CMC SNMPD dependencies
   define servicedependency {
       hostgroup_name                  cmc
       service_description             Check_SNMPDv3
       dependent_service_description   Check_CMC_Status
       execution_failure_criteria      c,p,u,w
       notification_failure_criteria   c,p,u,w
   }

7. Define hosts in your Nagios configuration for each CMC-TC device. In this example its named cmc-host1:

   define host {
       use         cmc
       host_name   cmc-host1
       alias       Rittal CMC LPC
       address     10.0.0.1
       parents     parent_lan
   }

   Replace cmc with your Nagios host template for the CMC-TC devices. Adjust the address and parents parameters according to your environment.

8. Define a hostgroup in your Nagios configuration for all CMC-TC devices. In this example it is named cmc. The above checks are run against each member of the hostgroup:

   define hostgroup {
       hostgroup_name  cmc
       alias           Rittal CMC
       members         cmc-host1
   }

9. Run a configuration check and if successful reload the Nagios process:

   $ /usr/sbin/nagios3 -v /etc/nagios3/nagios.cfg
   $ /etc/init.d/nagios3 reload

The new hosts and services should soon show up in the Nagios web interface.

If the Nagios server is running SNMPTT and was configured as a SNMP trap receiver in step number 1 in the above list, SNMPTT also needs to be configured to be able to understand the incoming SNMP traps from CMC-TC devices. This can be achieved by the following steps:

1. Convert the Rittal SNMP MIB definitions in CMC-TC_MIB_v1.1h.txt into a format that SNMPTT can understand.

   $ /opt/snmptt/snmpttconvertmib --in=MIB/CMC-TC_MIB_v1.1h.txt --out=/opt/snmptt/conf/snmptt.conf.rittal-cmc-tc
   
   ...
   Done
   
   Total translations:        10
   Successful translations:   10
   Failed translations:       0

2. The trap severity settings should be pretty reasonable by default, but you can edit them according to your requirements with:

   $ vim /opt/snmptt/conf/snmptt.conf.rittal-cmc-tc

3. Add the new configuration file to be included in the global SNMPTT configuration and restart the SNMPTT daemon:

   $ vim /opt/snmptt/snmptt.ini
   
   ...
   [TrapFiles]
   snmptt_conf_files = <<END
   ...
   /opt/snmptt/conf/snmptt.conf.rittal-cmc-tc
   ...
   END
   
   $ /etc/init.d/snmptt reload

4. Download the Nagios plugin check_snmp_traps.sh and place it in the plugins directory of your Nagios system, in this example /usr/lib/nagios/plugins/:

   $ mv -i check_snmp_traps.sh /usr/lib/nagios/plugins/
   $ chmod 755 /usr/lib/nagios/plugins/check_snmp_traps.sh

5. Define the following Nagios command to check for SNMP traps in the SNMPTT database. In this example this is done in the file /etc/nagios-plugins/config/check_snmp_traps.cfg:

   # check for snmp traps
   define command {
       command_name    check_snmp_traps
       command_line    $USER1$/check_snmp_traps.sh -H $HOSTNAME$:$HOSTADDRESS$ -u <user> -p <pass> -d <snmptt_db>
   }

   Replace user, pass and snmptt_db with values suitable for your SNMPTT database environment.

6. Add another service in your Nagios configuration to be checked for each CMC device:

   # check snmptraps
   define service {
       use                     generic-service
       hostgroup_name          cmc
       service_description     Check_SNMP_traps
       check_command           check_snmp_traps
   }

7. Optional: Define a serviceextinfo to display a folder icon next to the Check_SNMP_traps service check for each CMC device. This icon provides a direct link to the SNMPTT web interface with a filter for the selected host:

   define  serviceextinfo {
       hostgroup_name          cmc
       service_description     Check_SNMP_traps
       notes                   SNMP Alerts
       #notes_url               http://<hostname>/nagios3/nagtrap/index.php?hostname=$HOSTNAME$
       #notes_url               http://<hostname>/nagios3/nsti/index.php?perpage=100&hostname=$HOSTNAME$
   }

   Uncomment the notes_url depending on which web interface (nagtrap or nsti) is used. Replace hostname with the FQDN or IP address of the server running the web interface.

8. Run a configuration check and if successful reload the Nagios process:

   $ /usr/sbin/nagios3 -v /etc/nagios3/nagios.cfg
   $ /etc/init.d/nagios3 reload

9. Optional: If you're running PNP4Nagios v0.6 or later to graph Nagios performance data, you can use the check_cmc_status.php PNP4Nagios template to beautify the graphs. Download the PNP4Nagios template check_cmc_status.php and place it in the PNP4Nagios template directory, in this example /usr/share/pnp4nagios/html/templates/:

   $ mv -i check_cmc_status.php /usr/share/pnp4nagios/html/templates/
   $ chmod 644 /usr/share/pnp4nagios/html/templates/check_cmc_status.php

   The following image shows an example of what the PNP4Nagios graphs look like for a Rittal CMC-TC with a LCP-T3+ unit:

   

All done, you should now have a complete Nagios-based monitoring solution for your Rittal CMC-TC and LCP devices.