R3166-R3206-HP High-End Firewalls Network Management Configuration Guide-6PW101

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To do... Use the command... Remarks
Enter system view
system-view
Enable IP multicast routing
multicast routing-enable
Required
Disable by default
Enter interface view
interface interface-type
interface-number
Enable PIM-DM pim dm
Required
Disabled by default
CAUTION:
PIM-DM does not work with multicast groups in the SSM group grange.
Enabling State-Refresh capability
Pruned interfaces resume multicast forwarding when the pruned state times out. To prevent this, the router
with the multicast source attached periodically sends an (S, G) state-refresh message, which is forwarded
hop by hop along the initial multicast flooding path of the PIM-DM domain, to refresh the prune timer
state of all the routers on the path. A multi-access subnet can have the state-refresh capability only if the
state-refresh capability is enabled on all PIM routers on the subnet.
Follow these steps to enable the state-refresh capability:
To do... Use the command... Remarks
Enter system view
system-view
Enter interface view
interface interface-type
interface-number
Enable state-refresh
pim state-refresh-capable
Optional
Enabled by default
Configuring State-Refresh parameters
The router directly connected with the multicast source periodically sends state-refresh messages. You can
configure the interval for sending such messages.
A router may receive multiple state-refresh messages within a short time, of which some may be
duplicated messages. To keep a router from receiving such duplicated messages, you can configure the
time the router must wait before receiving the next state-refresh message. If a new state-refresh message
is received within the waiting time, the router will discard it; if this timer times out, the router will accept
a new state-refresh message, refresh its own PIM-DM state, and reset the waiting timer.
The TTL value of a state-refresh message decrements by 1 whenever it passes a router before it is
forwarded to the downstream node until the TTL value comes down to 0. In a small network, a
state-refresh message may cycle in the network. To effectively control the propagation scope of
state-refresh messages, you need to configure an appropriate TTL value based on the network size.
It is recommended to perform the following configurations on all routers in the PIM domain.
Follow these steps to configure state-refresh parameters:
To do... Use the command... Remarks
Enter system view
system-view