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Figure 57. NDP Router Redirect
IPv6 Neighbor Discovery of MTU Packets
You can set the MTU advertised through the RA packets to incoming routers, without altering the actual MTU setting on the
interface.
The ipv6 nd mtu command sets the value advertised to routers. It does not set the actual MTU rate. For example, if you set
ipv6 nd mtu to 1280, the interface still passes 1500-byte packets, if that is what is set with the mtu command.
Configuring the IPv6 Recursive DNS Server
You can configure up to four Recursive DNS Server (RDNSS) addresses to be distributed via IPv6 router advertisements
to an IPv6 device, using the ipv6 nd dns-server ipv6-RDNSS-address {lifetime | infinite} command in
INTERFACE CONFIG mode.
The lifetime parameter configures the amount of time the IPv6 host can use the IPv6 RDNSS address for name resolution. The
lifetime range is 0 to 4294967295 seconds. When the maximum lifetime value, 4294967295, or the infinite keyword is
specified, the lifetime to use the RDNSS address does not expire. A value of 0 indicates to the host that the RDNSS address
should not be used. You must specify a lifetime using the lifetime or infinite parameter.
The DNS server address does not allow the following:
● link local addresses
●
loopback addresses
● prefix addresses
● multicast addresses
● invalid host addresses
If you specify this information in the IPv6 RDNSS configuration, a DNS error is displayed.
Example for Configuring an IPv6 Recursive DNS Server
The following example configures a RDNNS server with an IPv6 address of 1000::1 and a lifetime of 1 second.
DellEMC(conf-if-te-1/1/1)#ipv6 nd dns-server ?
X:X:X:X::X Recursive DNS Server's (RDNSS) IPv6 address
DellEMC(conf-if-te-1/1/1)#ipv6 nd dns-server 1000::1 ?
<0-4294967295> Max lifetime (sec) which RDNSS address may be used for name
resolution
infinite Infinite lifetime (sec) which RDNSS address may be used for name
resolution
422
IPv6 Routing