Configuring SNMP Trap Destinations with FQDNs

Instead of configuring SNMP trap destinations (Trap Managers) with IP addresses in the SNMP Trap Destinations table (see Configuring SNMP Trap Destination with IP Addresses), you can configure the address of SNMP Trap Managers with FQDNs (hostnames). You can configure two hostnames (i.e., two Trap Managers) - one for resolving into an IPv4 address and one for resolving into an IPv6 address. The device sends traps to the Trap Managers using these DNS-resolved IP addresses.

Depending on IP version, the device automatically adds the DNS-resolved IP addresses to the following SNMP Managers in the SNMP Trap Destinations table:

IPv4: The DNS-resolved IPv4 address is added to 'SNMP Manager 5' (last entry in the snmpTargetAddrTable in the snmpTargetMIB), overwriting the existing address (if any).
IPv6: The DNS-resolved IPv6 address is added to 'SNMP Manager 4', overwriting the existing address (if any).
If you configure an FQDN for an SNMP Trap Manager, the device ignores all your manual configuration (if any) in the SNMP Trap Destinations table.
The IP address version (IPv4 or IPv6) of the FQDN and IP Interface (in the IP Interfaces table) must be the same. For assigning IP Interfaces for SNMP, see Configuring SNMP Interfaces.
To resolve the FQDN into an IP address, the device uses the DNS server configured in the IP Interfaces table of the corresponding IP Interface.
If you delete the FQDN, the device removes the corresponding DNS-resolved address from the SNMP Trap Destinations table.
If the DNS response contains multiple DNS-resolved IP addresses, the device uses only the first IP address in the list.
To configure an SNMP trap destination with an FQDN:
1. Open the SNMP Community Settings page (Setup menu > Administration tab > SNMP folder > SNMP Community Settings).
2. In the 'Trap Manager Host Name for IPv4' field [SNMPTrapManagerHostName], enter the FQDN for IPv4 address resolution. This address is used for Trap Manager 5.
3. In the 'Trap Manager Host Name for IPv6' field [SNMPIPv6TrapManagerHostName], enter the FQDN for IPv6 address resolution. This address is used for Trap Manager 4.

4. Click Apply.