L3 Hash Table

The L3 hash table is introduced in Introduction to Hardware Forwarding Tables. The L3 hash table stores entries for IPv4 routes, IPv4 and IPv6 hosts, and IPv4 and IPv6 multicast groups. For multicast, L3 hash table supports <S,G,V> and <*,G,V> lookups. The entry from this table provides an index to IP Multicast Group table.

To make more space available in the L3 hash table for IPv4 and IPv6 multicast groups, you can do the following:

• Configure the extended IPv4 host cache feature to move IPv4 local and remote routes to the LPM table as described in Extended IPv4 Host Cache.

• For more information, see the description for the configure iproute reserved-entries command.