When an SNMP request is sent to a device associated with a protocol the request will be sent to the policy UDP port using the policy username as SNMP community and version. In order for request to be successful the policy has to match the SNMP configuration of the target device.
Successful request will result in a number of packets each containing a number of OIDs set by the Repeaters parameter (this is a number of SNMP request repeats in one SNMP Query). If the request is unsuccessful, there will be a number of retries (Retries parameter) with a certain timeout between each request based on the Timeout parameter (timeout incrementally grows after each request).
In the example shown in the screenshot above the SNMP request in view mode will result in a SNMPv3 request to a device on UDP port 161 with the above set security parameters. If the device doesn't reply, there will be one more retry after 1000ms.
Removing SNMP Policy
To remove a policy, click - (remove icon) in the Action column.