DHCPv6 Relay Agent Prefix Delegation Notification limitations

The following limitations apply to DHCPv6 Relay Agent Prefix Delegation Notification.

  • The PD notification fails when the DHCPv6 messages between a DHCPv6 server and a DHCPv6 client containing the PD option are not relayed by way of the DHCPv6 relay agent.
  • If the delegated prefix is released or renewed by the client at the time when the DHCPv6 relay agent is down or rebooting, then this release or renewal of the delegated prefix will not be detected by the relay agent. In such a condition, there could be stale static routes in the routing table. You must clear the stale routes.
  • If there is no sufficient disk space on a flash disk, then the system may not store all the delegated prefixes in the IPv6 route table.

  • The DHCPv6 PD flash operation depends on the NTP clock synchronization. During system bootup, if the NTP is configured, the flash operation (dhcp6_delegated_prefixes_data flash file read/write) is delayed until the NTP is synchronized. The NTP synchronization is needed for the correct updating of the prefix age. If the NTP is not configured, then the DHCP prefix delegation will still read the flash, but the prefix age may not be correct.

Parent topic: DHCP relay agent for IPv6