Configuring The Multicast Forwarding Table Size - HP A6600 Configuration Manual

Configuring the multicast forwarding table size

The router maintains the corresponding forwarding entry for each multicast packet that it receives.
Excessive multicast routing entries, however, can exhaust the router's memory and cause lower router
performance. You can set a limit on the number of entries in the multicast forwarding table based on the
networking situation and the performance requirements. If the configured maximum number of multicast
forwarding table entries is smaller than the current value, the forwarding entries in excess will not be
deleted immediately. Instead, the multicast routing protocols that are running on the router will delete
them. The router will no longer add new multicast forwarding entries until the number of existing multicast
forwarding entries comes down under the configured value.
When forwarding multicast traffic, the router replicates a copy of the multicast traffic for each
downstream node and forwards the traffic. Thus, each of these downstream nodes forms a branch of the
multicast distribution tree. You can configure the maximum number of downstream nodes (namely, the
maximum number of outgoing interfaces) for a single entry in the multicast forwarding table to lessen the
burden on the router for replicating multicast traffic. If the configured maximum number of downstream
nodes for a single multicast forwarding entry is smaller than the current number, the downstream nodes in
excess will not be deleted immediately. Instead, the multicast routing protocols that are running on the
router will delete them. The router will no longer add new multicast forwarding entries for newly added
downstream nodes until the number of existing downstream nodes comes down under the configured
value.
Configuring the multicast forwarding table size for the public network
To do...
1. Enter system view.
2. Configure the maximum
number of entries in the
multicast forwarding table.
3. Configure the maximum
number of downstream nodes
for a single multicast
forwarding entry.
Configuring the multicast forwarding table size in a VPN instance
To do...
1. Enter system view.
2. Enter VPN instance view.
3. Configure the maximum
number of entries in the
multicast forwarding table.
4. Configure the maximum
number of downstream nodes
for a single route in the
multicast forwarding table.
Use the command...
system-view
multicast forwarding-table
route-limit limit
multicast forwarding-table
downstream-limit limit
Use the command...
system-view
ip vpn-instance vpn-instance-name
multicast forwarding-table
route-limit limit
multicast forwarding-table
downstream-limit limit
52
Remarks
—
Optional.
4096 by default.
Optional.
128 by default.
Remarks
—
—
Optional.
4096 by default.
Optional.
128 by default.