How to get OID from MIB
Use Passler MIB Importer ( https://www.paessler.com/tools/mibimporter ) to get your .mib’s into .oidlib
File Open
Then File Save As
Find the Oid list for the device
http://www.oidview.com/mibs/5951/NS-ROOT-MIB.html
Get information about the Oid
http://oid-info.com/cgi-bin/display?oid=%091.3.6.1.4.1.5951.4.1.1.12&action=display
Login to Nable and add Custom Service
Add -> Service -> SNMP
Add Oid
Add Metric for Oid
Use the information you gathered from oid-info.com to help you define what value you will be given e.g. String , Booleon or Number
Modify threshold for Normal/Warning and Faily
Perform maths between Oids using Calculation to Use
Apply Custom service to device , make sure device is using professional license for SNMP and SNMP is open on the device with correct version