General Filter rules
By default, Monitor one accepts traps from any host. UNCHECK the Accept Traps from any host checkbox to accept only traps from devices that have been added to the network map. The advantage of not-checking this checkbox is of course that you only get traps of "known" devices. The disadvantage is that you could "miss" traps sent by devices that have been added to the network map but that use other IP addresses than the ones specified on the network map! This could be the case when devices have more than one interface and IPaddress (Routers, multi-homed Hosts etc).
Generic Trap filter filter rules (SNMPv1)
See the screenshot below:
The screenshot shows some generic trap filter rules. All Generic traps are accepted except the Authentication failure trap for all enterprises, LinkUp and LinkDown traps received from HP j4813A switches and the coldStart and linkup traps received from Microsoft systems.
Use the "PHASE I" checkboxes to specify which Generic traps to accept or to block regardless of the enterprise. The "PHASE II" filter rules take the enterprise of the received traps into account.
"PHASE II" rules cannot be entered directly into the filtering table above. Monitor one provideds another way to add PHASE II filter rules. By default, all Generic traps that pass through the "PHASE I" filter are shown in the "Trap control" (select Options|Trap control from the main Monitor one window) window. If you are certain that you do not want to receive a specific generic trap any longer, you can right-click the trap in the "Trap control" window and select Block this trap type from now on (Add a new filter rule). A new filter rule (describing the trap you want to block in the future) is added automatically to the PHASE II table!
Enterprise Specific trap filter rules (SNMPv1,SNMPv2).
EnterpriseSpecific Trap filtering slightly differs from Generic Trap filtering!
Use the Enterprise listbox to select an enterprise. The filter rules belonging to the selected Enterprise are shown in the list. New Enterprises and trap descriptions come available when new MIB files are compiled.
If you right-click a filter rule you can choose either Block this Trap type or Accept this Trap type.
Check the Accept unknown EnterpriseSpecific Traps… checkbox to specify what needs to be done in case of receiving a trap for which no MIB information is available.
Just as with Generic Traps, new rules can be added to the set of Enterprise Specific filter rules by right-clicking traps in the "Trap control" window and choosing Block this trap type from now on.