Why my M580 SNMP service does not respond ?

----------------------------------------------------------------------------------------------------
Context:
- All CPUs are concerned (BMEx58x0x0x)
- CPU configured with SNMP services (both IPs: IPA and IP Main)
- IP A and IP Main are not on the same subnetwork (IP A = 192.168.11.3/24 and IP Main = 192.168.10.1/24)
- but a router is only set on one of the both subnetwork (i.e. 192.168.10.254/24 )

----------------------------------------------------------------------------------------------------
Behaviour:
Randomly, on boot CPU phase, communication are starting with SNMP using IP A, SNMP services are not responding. => because router is only set for 192.168.10.x addresses.

----------------------------------------------------------------------------------------------------
Nota:
This boot phase and random behaviour are documented into "Modicon M580, Hardware Reference Guide" (ref. EIO0000001578) into chapter "Installing Modules in an M580 Rack"/"Services and Addresses"



----------------------------------------------------------------------------------------------------
Troubleshooting:
To avoid SNMP packet filtering from the router, we recommand to configure the router subnetwork mask to 255.255.0.0 (16) instead of 255.255.255.0 (24)

----------------------------------------------------------------------------------------------------
Appendix 1: Example of IP Main and IP A


----------------------------------------------------------------------------------------------------
Appendix 2: example of SNMP Manager

Released for:Schneider Electric Ireland