SNMP Trap Receiver Snmptrapd.conf File
The SNMP Trap engine that responds to Trap messages requires a configuration file named snmptrapd.conf to direct its functionality, primarily in terms of authorization. This page allows automated generation of that file, but with the option to manually edit it.
The SNMP engine in this IoTServer is the widely used open source Net-SNMP package. If you are concerned about manually editing the snmptrapd.conf file, simple search the Internet for Net-SNMP documentation - there is much to be found.
The port on which SNMP listens for Trap messages defaults to the standard port 162. You may change it here if you wish.
Authorization for access in SNMPv1 and SNMPv2 is very simply. You only need to match the community names which are treated sort of like a password. If using SNMP v1 or v2 (v2c), enter your community strings here. Trap messages received as v1 or v2 will be expected to match this community.
Click the Generate Config button to auto-generate an snmptrapd.conf file. Parameters included in the file will be taken from two places: (1) The entries showing above on this page. (2) User settings from the System -> Users page (if SNMPv3).
SNMPv3 enforces access only by known users. These users may be a person or may be anther machine, but must be defined as a "user" either way. To permit SNMPv3 Traps (or Informs) to be received, go to the System -> Users page and create a "user" for each person or machine that will send Traps to this IoTServer. Once the users are created, and they have been selected for SNMPv3 Trap access, they will be automatically included in the snmptrapd.conf file generated here.
Once the interim snmptrapd.conf file is generated, it may be viewed and optionally edited here. The file content displayed here is not actually saved to a file until you click the Save button at the bottom. When Save is clicked, the file name given will be created or overwritten with the content currently displayed.
There are two more steps required to complete the reconfiguration of the SNMP Trap Receiver. Go to the SNMP Trap Receiver Config File page, select the newly created interim snmptrapd.conf file, and click the Load button (as discussed on the SNMP Trap Receiver Config File page). Finally, after loading the new snmptrapd.conf file, click Restart SNMP at the bottom of the Config File page.