How To Monitor Network Switch and Ports Using Nagios. Nagios is hands down the best monitoring tool to monitor host and network equipments. Using Nagios plugins you can monitor pretty much monitor anything. I use Nagios intensively and it gives me peace of mind knowing that I will get an alert on my phone, when there is a problem. More than that, if warning levels are setup properly, Nagios will proactively alert you before a problem becomes critical. Earlier I wrote about, how to setup Nagios to monitor Linux Host, Windows Host and VPN device. In this article, Ill explain how to configure Nagios to monitor network switch and its active ports. Enable switch. cfg in nagios. Uncomment the switch. Add new hostgroup for switches in switch. I.png.c06fa925d3a735edb2bd847584d4febe.png' alt='Install Snmp Windows Server 2008' title='Install Snmp Windows Server 2008' />Add the following switches hostgroup to the usrlocalnagiosetcobjectsswitch. Network Switches. Add a new host for the switch to be monitered. In this example, Ive defined a host to monitor the core switch in the usrlocalnagiosetcobjectsswitch. Change the address directive to your switch ip address accordingly. Cisco Core Switch. Add common services for all switches. Install Snmp Windows Server 2008' title='Install Snmp Windows Server 2008' />What you will need Windows server running WDS and working via DHCP. A recent copy of SYSLINUX extracted to a folder somewhere on the WDS server. Versatile range of use from SOHO to large enterprises. Connects with a variety of server types N7100 easily satisfies the digitizing needs of small office networks. MongoDB Enterprise Install on Linux Install the official builds of MongoDB Enterprise on Linuxbased systems. Install on OS X Install the official build of MongoDB. SolarWinds SNMP Walk A new tool for collecting SNMP MIB walks 500 Internal Server Error 500 Internal Server Error during additional web server installation. Displaying the uptime of the switch and verifying whether switch is alive are common services for all switches. So, define these services under the switches hostgroupname as shown below. Service definition to ping the switch using checkping. PING. checkcommand checkpingSecurity guidelines for disabling services in Windows Server 2016 with Desktop Experience. This video shows you how to install and configure PRTG Network Monitor on a Windows Server 2012 R2 Operating System. Service definition to monitor switch uptime using checksnmp. Uptime. checkcommand checksnmp C public o sys. Up. Time. 0. 5. Add service to monitor port bandwidth usagechecklocalmrtgtraf uses the Multil Router Traffic Grapher MRTG. So, you need to install MRTG for this to work properly. The. log file mentioned below should point to the MRTG log file on your system. Port 1 Bandwidth Usage. AVG 1. 00. 00. 00,2. Add service to monitor an active switch port. Use checksnmp to monitor the specific port as shown below. The following two services monitors port1 and port5. To add additional ports, change the value if. Oper. Status. n accordingly. Monitor status of port number 1 on the Cisco core switch. Port 1 Link Status. 3 Types Of Software Maintenance. C public o if. Oper. Status. 1 r 1 m RFC1. MIB. Monitor status of port number 5 on the Cisco core switch. Port 5 Link Status. C public o if. Oper. Status. 5 r 1 m RFC1. MIB. 7. Add services to monitor multiple switch ports together. Sometimes you may need to monitor the status of multiple ports combined together. Nagios should send you an alert, even if one of the port is down. In this case, define the following service to monitor multiple ports. Monitor ports 1 6 on the Cisco core switch. Ports 1 6 Link Status. C public o if. Oper. Status. 1 r 1 m RFC1. MIB, o if. Oper. Status. RFC1. MIB, o if. Oper. Status. 3 r 1 m RFC1. MIB, o if. Oper. Status. RFC1. MIB, o if. Oper. Status. 5 r 1 m RFC1. MIB, o if. Oper. Status. RFC1. MIB. 8. Validate configuration and restart nagios. Verify the nagios configuration to make sure there are no warnings and errors. Total Warnings 0. Total Errors 0. Things look okay No serious problems were detected during the pre flight check. Restart the nagios server to start monitoring the VPN device. Stopping nagios. Starting nagios done. Verify the status of the switch from the Nagios web UI http nagios servernagios as shown below Fig Nagios GUI displaying status of a Network Switch. Troubleshooting. Issue. Nagios GUI displays checkmrtgtraf Unable to open MRTG log file error message for the Port bandwidth usage. Solution. 1 make sure the Issue. Nagios UI displays Return code of 1. Port Link Status. Solution. 2 Make sure both net snmp and net snmp util packages are installed. In my case, I was missing the net snmp utils package and installing it resolved this issue as shown below. EL4. 1. 0. i. 38. Preparing. 1. EL4. Note After youve installed net snmp and net snmp utils, re compile and re install nagios plugins as explained in 6. Compile and install nagios plugins in the Nagios 3. Two Best Nagios Books. These are the two best nagios books that covers the latest Nagios 3. I strongly recommend that you read both of these books to gain a detailed understanding on Nagios. Since Nagios is free software, spending few dollars on the books can be the best investment you can make. Awesome Nagios Articles. Following are few awesome Nagios articles that you might find helpful. If you enjoyed this article, you might also like.