HP 6125XLG - Configuring Ipv6 PIM-DM Graft Retry Timer; Configuring State Refresh Parameters

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domain to refresh the prune timer state of all the routers on the path. A shared-media subnet can have the
state refresh feature only if the state refresh feature is enabled on all IPv6 PIM routers on the subnet.
To enable the state refresh feature on all routers in IPv6 PIM-DM domain:
Ste
p
Command Remarks
1. Enter system view.
system-view
N/A
2. Enter interface view.
interface interface-type
interface-number
N/A
3. Enable the state refresh
feature.
ipv6 pim state-refresh-capable
By default, the state refresh feature
is enabled.
Configuring state refresh parameters
The router that directly connects to the IPv6 multicast source periodically sends state refresh messages.
You can configure the interval for sending such messages on that router.
A router might receive duplicate state refresh messages within a short time. To prevent this situation, you
can configure a waiting timer for the router. The router starts a timer when it receives a state refresh
message. If the router receives state refresh messages before the timer expires, it discards the messages.
If the router receives a new state refresh message after the timer expires, it refreshes its own IPv6 PIM-DM
state and restarts a waiting timer.
After a router receives a state refresh message, it decreases the hop limit value of the message by 1 and
forwards the message to the downstream node. The forwarding process stops when the hop limit value
comes down to 0. In a small network, a state refresh message might cycle in the network. To control the
propagation scope of state refresh messages, configure an appropriate hop limit value based on the
network size on the router that directly connects to the IPv6 multicast source.
To configure state refresh parameters:
Ste
p
Command Remarks
1. Enter system view.
system-view
N/A
2. Enter IPv6 PIM view.
ipv6 pim [ vpn-instance
vpn-instance-name ]
N/A
3. Configure the interval to send
state refresh messages.
state-refresh-interval interval
By default, the interval to send
refresh messages is 60 seconds.
4. Configure the time to wait
before receiving a new state
refresh message.
state-refresh-rate-limit time
By default, the waiting time is 30
seconds.
5. Configure the hop limit value
of state refresh messages.
state-refresh-hoplimit
hoplimit-value
By default, the hop limit value of
state refresh messages is 255.
Configuring IPv6 PIM-DM graft retry timer
In IPv6 PIM-DM, only the graft process uses the acknowledgment mechanism. After a router sends a graft
message, it starts a graft retry timer. If the router does not receive a graft-ack message from the upstream
router when the timer expires, the router sends another graft message. The router keeps sending graft
messages until it receives a graft-ack message.