On implementation of SNMP with Zabbix we hit a strange problem on 2 of the 20 devices of a customer (all Balance models 30 to 580)
All devices are PEPVPN connected to the central HUB, so all is routable. We enabled SNMP on the devices with subnet filter and community string. On 18 devices it worked straight after config.
On 2 devices we were unable to snmpwalk on the devices and at first we did not find a reason for it.
After some searching and trying, we noticed a sligth difference in config of the “SYSTEM >> Admin Security”
The 2 devices were configed with “LAN Connection Access Settings” set on “Allow this network only”
And a local site network chosen. After changing the setting to “Any” the SNMPwalk was possible.
This setting has direct effect on the SNMP settings. In some way you could say this is by design.
But we were connecting trough a PEPVPN the IP address of the chosen Interface (local network)
So it is source IP filtered I think, and not by incomming interface.
The question is, is this behaviour by design or is this a bug, should this be independ settings?