Close to thirty percent of our support tickets are related to ManageEngine monitoring applications not pulling statistics from network devices or servers. That is where MIB Browser comes in handy. It is a tool that performs SNMP operation to GET or SET values on network devices and servers. I prefer calling it a troubleshooting tool as it helped me solve many trouble tickets.
A little bit on SNMP before I get to some of the ‘how –to’ of this tool.
Many network devices and servers support SNMP (Simple Network Management Protocol) to fetch statistic details as well as to set configuration parameters.
MIB stands for Management Information Base. It is a collection of information organized hierarchically and it can be accessed using SNMP Protocol. Most vendors maintain and control their own MIB structure.
OIDs stand for Object Identifiers. It identifies individual managed objects within the MIB hierarchy.
Working with MIB Browser:
Load the MIB you want to query against the device. For example, in the following screenshot I have selected SNMP v2 MIB and browsed to the OID called sysDescr. It gives details about the system such as full name and version identification of Hardware type, Software etc. To know what the OID represents, I recommend administrators to check the Description field. This ensures that you are looking at the right information.
You can provide name or IP address in the Host field. I have entered READ only community string as I am only fetching the details. Now, click the Get icon to fetch the information.
Device responded with the system details like Cisco IOS software, version 15.3 etc.
Let us see how Host Name can be fetched from Cisco router using Cisco mib. Load Cisco-MIB as
shown below and query the device.
You cannot use CISCO-MIB to query Juniper or any other network devices. Also, not all cisco devices, say Cisco ASA Firewall, may respond to this MIB. As mentioned earlier, check the details with the vendors as they have control over their mibs.
This tool helped me narrow down the cause and identify why performance statistics was not collected from devices. A few common causes were SNMP not being enabled on the monitored device, mib not supported by the device and sometime, the issues are related to the NMS product itself.
SNMP MIBBrowser is the most popular free tool from ManageEngine. Did you know that this tool is available as an independent download for Linux and MAC OSes as well? You can find the links to the relevant downloads here:
So, what tool do you use in your environment to troubleshoot SNMP related issue? I would also like to hear the kind of road-blocks you hit into when it comes to relying on SNMP for monitoring your IT resources.