Hi, I have enabled the SNMP agent on a Cat 3560G and have downloaded and parsed various Cisco mibs, including the CISCO-STP-EXTENSIONS-MIB.my mib, in to our MIB browser. This has enabled me to successfully set the bridge spanning-tree mode to mst and configure the mst name and revision level using SNMP. However, I cannot locate the mib object to set or get the instance priority or the port costs and port priorities for each instance. I can successfully set these via CLI. Does anybody know if these objects exist in a different MIB? I have searched many mibs but have been unable to locate them.
Many thanks in advance.
These values are typically set using BRIDGE-MIB objects, however, I have not tested this with MST. You will need to use community string indexing at the very least to do this on a per-instance basis. Your indexes will be mst-X where X is the instance number. For example, "private@mst-2" would be a community string to set objects in MST instance 2.
Then try setting dot1dStpPortPriority or dot1dStpPortPathCost for the port ID you want using that community string.
Or set dot1dStpPriority.0 using that community string.
Many thanks for this - you are right. I performed 'snmp-server community private@mst-x rw' where x is an incremental number representing the instance.
Instance Priority: With the above it is now possible to read the instance priority from BRIDGE-MIB::dot1dstpPriority.0 by quoting the appropriate community string for the instance i.e. 'snmpget -c private@mst-1 -v 2c
Port Priority: This works as expected with the correct community string getting and setting 'BRIDGE-MIB::dot1dstpPortPriority.
Port Cost: I have been having problems with this one. I can get the cost by performing 'snmpget -c private@mst-1 -v 2c
The software running is Version 12.2(25r)SE1, Release Software (fc).
I have noticed that it is possible to get the port state from dot1dStpPortState but there is no equivalent for port Role - which is available via CLI.