H3C Technologies H3C SecPath F1000-E - Manual (Page 871)

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Configuring an IPv6 multicast forwarding range
IPv6 multicast packets do not travel infinitely in a network. The IPv6 multicast data of each IPv6 multicast
group must be transmitted within a definite scope. You can define an IPv6 multicast forwarding range by
specifying boundary interfaces, which form a closed IPv6 multicast forwarding area.
You can configure the forwarding boundary for a specific IPv6 multicast group or an IPv6 multicast group
with the scope field in its group address being specified on all interfaces that support IPv6 multicast
forwarding. A multicast forwarding boundary sets the boundary condition for the IPv6 multicast groups
in the specified range or scope. If the destination address of an IPv6 multicast packet matches the set
boundary condition, the packet will not be forwarded. Once an IPv6 multicast boundary is configured
on an interface, this interface can no longer forward IPv6 multicast packets (including those sent from the
local device) or receive IPv6 multicast packets.
To configure an IPv6 multicast forwarding range:
Step Command Remarks
1. Enter system view. system-view N/A
2. Enter interface view.
interface interface-type
interface-number
N/A
3. Configure an IPv6 multicast
forwarding boundary.
multicast ipv6 boundary
{ ipv6-group-address prefix-length
| scope { scope-id | admin-local |
global | organization-local |
site-local } }
No forwarding boundary by
default
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
router performance. You can set a 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 maximum
number of IPv6 multicast forwarding table entries is smaller than the current value, the entries in excess
will not be immediately deleted. Instead, the IPv6 multicast routing protocol that running 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 comes down under the configured value.
When forwarding IPv6 multicast traffic, the router replicates a copy of the IPv6 multicast traffic for each
downstream node and forwards the traffic, and thus each of these downstream nodes forms 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 maximum
number of downstream nodes for a single IPv6 multicast forwarding entry is smaller than the current
number, the downstream nodes in excess will not be deleted immediately. Instead, the IPv6 multicast
routing protocol will delete them. The router will no longer install new IPv6 multicast forwarding entries
for newly added downstream nodes until the number of existing downstream nodes comes down under
the configured value.
To configure the IPv6 multicast forwarding table size: