R3303-HP HSR6800 Routers IP Multicast Configuration Guide
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Configuring the IPv6 multicast forwarding table size
The router maintains the corresponding forwarding entry for each IPv6 multicast packet that it receives.
Excessive IPv6 multicast routing entries, however, can exhaust the router's memory and cause lower
performance. You can set an upper limit on the number of entries in the IPv6 multicast forwarding table
based on the actual networking situation and the performance requirements. If the configured upper limit
is smaller than the number of existing entries in the IPv6 multicast forwarding table, the entries in excess
are not deleted immediately. The IPv6 multicast routing protocol that runs on the router will delete them.
The router will no longer install new IPv6 multicast forwarding entries until the number of existing IPv6
multicast forwarding entries decreases below the upper limit.
When the router forwards IPv6 multicast data, it replicates a copy of the IPv6 multicast data for each
downstream node and forwards the data. Each of these downstream nodes is a branch of the IPv6
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 IPv6 multicast forwarding table to
lessen the burden on the router for replicating IPv6 multicast traffic. If the configured upper limit is smaller
than the number of existing downstream nodes for a forwarding entry, the downstream nodes in excess
are not deleted immediately. The IPv6 multicast routing protocol will delete them. The router will no
longer update the newly added downstream nodes for the forwarding entry until the number of existing
downstream nodes for the entry decreases below the upper limit.
To configure the IPv6 multicast forwarding table size:
Ste
p
Command
Remarks
1. Enter system view.
system-view N/A
2. Configure the maximum
number of entries in the IPv6
multicast forwarding table.
multicast ipv6 forwarding-table
route-limit limit
Optional.
The default value is 1024.
3. Configure the maximum
number of downstream nodes
for a single IPv6 multicast
forwarding entry.
multicast ipv6 forwarding-table
downstream-limit limit
Optional.
The default value is 128.
Configuring IPv6 static multicast MAC address entries
This feature is available only on the router that is installed with the SAP module.
In Layer-2 multicast, a Layer-2 IPv6 multicast protocol (such as MLD snooping) can dynamically add IPv6
multicast MAC address entries. Or, you can manually configure IPv6 multicast MAC address entries.
When you configure IPv6 static multicast MAC address entries, follow these guidelines:
• When you configure a static multicast MAC address entry in system view, the configuration is
effective on the specified interfaces. When you configure a static multicast MAC address entry in
interface view or port group view, the configuration is effective only on the current interface or all
interfaces in the current port group.
• Any legal IPv6 multicast MAC address except 3333-xxxx-xxxx (where x represents a hexadecimal
number from 0 to F) can be manually added to the MAC address table. IPv6 multicast MAC
addresses are the MAC addresses whose the least significant bit of the most significant octet is 1.
Configuring an IPv6 static multicast MAC address entry in system view