I am OP 6.5 install and run for a while. It work fine with correct SNMP community and cisco 2960 switch.

The problem since I monitor 3 days with 5 min snapshot setting for more than 100 devices, the network device monitor data change into N/A instead of correct snapshot data ?

I change setting "Admin/SNMP Parameter" into 3 sec time out/5 times retry and won't get snapshot back to work ? Running MiB Browser is work fine ?

That's production environment which need to monitor about 150 devices with OP, what should be the cause which OP will lost monitor device ?

warren