The internal leases for local address assignment are not synchronized through the local DHCP server multi-chassis synchronization (MCS) application. Instead, the SLAAC prefix is synchronized to the standby BNG through the subscriber management PPPoE or IPoE application. The standby BNG then creates an internal lease in the local DHCP server to be used for the local address assignment. Local address assignments fail when local DHCP server failover is configured at the server or pool level.