we have 2 ISR4451 (IOS-XE) gateways configured as one CUBE HA pair. I would like to know how is it possible to monitor state of each gateway through SNMP - if its on ACTIVE,STANDBY or PROTECTED mode as you can see through CLI below.
This is very important because CUBE node which is on the PROTECTED state needs to be reloaded to start to work again as pair with the second node.
No I didn't :-(. I also openned TAC case and they confirmed to me that these parametres are not possible to be monitored over SNMP - there is NO MIB for this, really very unbelievable from Cisco that this is not there.
If you look to the available SNMP MIBs you will find that there is really huge number of unnecessary parametres that you can monitor over SNMP and on the other side there is also lot of parametres which are really important but are not available over SNMP :-).
There is just one option how to monitor this - EEM+TCL or scheduled TCL script from which you can send SNMP traps to the monitoring system.