After upgraded the PAM to latest version - 4.3.0.1654, your network monitoring tools are unable to connect to PAM using snmp, you stopped and started the 'Poll Server' service in Configuration- SNMP - Poll Server (Start and Stop) but snmp is not working.
Even rebooting the PAM Appliance does not fix the problem.
PAM 4.3
In this PAM version internal firewall is blocking the communication on port 161
The solution is included in PAM 4.3.1
If you need a solution for your current version please open up an issue in Broadcom Support to get help.