Configuring recursive DNS server addresses

RDNSS addresses allow IPv6 devices to advertise recursive DNS server addresses and lifetime multiplier values to IPv6 hosts in a local area network. The following task configures two DNS server addresses to be advertised for an Ethernet interface in router advertisement (RA) messages, and sets separate lifetime multiplier values for each of the DNS server addresses configured.
  1. Enter the configure terminal command to access global configuration mode. 
    device# configure terminal
  2. Enter the interface command and specify an interface. 
    device(config)# interface ethernet 1/1/3
  3. Enter the ipv6 nd ra-dns-server command, specifying an IPv6 address, to configure a DNS server to be advertised in RA messages. Use the lifetime-multiplier keyword, entering a value, to specify the maximum RA interval. 
    device(config-if-e1000-1/1/3)# ipv6 nd ra-dns-server 2001::1 lifetime-multiplier 1
  4. Enter the ipv6 nd ra-dns-server command, specifying an IPv6 address, to configure a DNS server to be advertised in RA messages. Use the lifetime-multiplier keyword, entering a value, to specify the value of the maximum RA interval. 
    device(config-if-e1000-1/1/3)# ipv6 nd ra-dns-server 2001::2 lifetime-multiplier 2

The following example configures a DNS server with the IPv6 address 2001::1 to be advertised in RA messages, with a lifetime multiplier of 1. It also configures a DNS server with the IPv6 address 2001::2 to be advertised in RA messages, with a lifetime multiplier of 2. 

device# configure terminal
device(config)# interface ethernet 1/1/3
device(config-if-e1000-1/1/3)# ipv6 nd ra-dns-server 2001::1 lifetime-multiplier 1 
device(config-if-e1000-1/1/3)# ipv6 nd ra-dns-server 2001::2 lifetime-multiplier 2
Parent topic: Recursive DNS server addresses