Operating notes for DHCPv6
-
A DHCPv6-relay message sent to any multicast address carries a hop limit of 32. The hop limit for DHCPv6 requests sent to a unicast address is determined by the
ipv6 hop-limit <1–255>
command at the global configuration level; Default: 64. -
Multicast addresses reserved for DHCPv6 include the following:
-
FF02::1:2—All_DHCP_Relay_Agents_and_Servers
-
FF05::1:3—All_DHCP_Servers
-
-
DHCPv6 client and relay functions are mutually exclusive on a VLAN. Attempting to configure one of these functions on a VLAN while the other is already configured results in one of the following messages:
Cannot configure an IPv6 helper–address as DHCPv6 client is enabled on the VLAN.
Cannot enable DHCPv6 client as an IPv6 helper–address is configured on the VLAN.
-
The routing switch supports concurrent, independent operation of DHCPv4 and DHCPv6.
-
Operating limits:1
DHCPv6-relay feature
Maximum
Unique Helper addresses supported on the routing switch
32 1
Unique Helper addresses per VLAN interface
32
If the same Helper address is used on multiple VLANs, it is counted as one address toward these maximums.