R3303-HP HSR6800 Routers IP Multicast Configuration Guide

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Analysis
• An IPv6 PIM routing entry is created based on an IPv6 unicast route, whichever IPv6 PIM mode is
running. Multicast works only when unicast does.
• IPv6 PIM must be enabled on the RPF interface. An RPF neighbor must be an IPv6 PIM neighbor as
well. If IPv6 PIM is not enabled on the RPF interface or the RPF neighbor, the establishment of a
multicast distribution tree will surely fail, resulting in abnormal multicast forwarding.
• IPv6 PIM requires that the same IPv6 PIM mode (namely, DM or SM) must run on the entire network.
Otherwise, the establishment of a multicast distribution tree will surely fail, resulting in abnormal
multicast forwarding.
Solution
1. Use the display ipv6 routing-table command to verify that a unicast route to the IPv6 multicast
source or the RP is available.
2. Use the display pim ipv6 interface command to verify the IPv6 PIM information on each interface,
especially on the RPF interface. If IPv6 PIM is not enabled on the interface, use the pim ipv6 dm or
pim ipv6 sm command to enable IPv6 PIM.
3. Use the display pim ipv6 neighbor command to verify that the RPF neighbor is an IPv6 PIM
neighbor.
4. Verify that IPv6 PIM and MLD are enabled on the interfaces directly connecting to the IPv6
multicast source and to the receiver.
5. Use the display pim ipv6 interface verbose command to verify that the same PIM mode is enabled
on the RPF interface and the corresponding interface of the RPF neighbor router.
6. Use the display current-configuration command to verify the IPv6 PIM mode information on each
interface. Make sure the same IPv6 PIM mode (IPv6 PIM-SM or IPv6 PIM-DM) is enabled on all
routers.
RPs cannot join the SPT in IPv6 PIM-SM
Symptom
An RPT cannot be established correctly, or the RPs cannot join the SPT to the IPv6 multicast source.
Analysis
• As the core of an IPv6 PIM-SM domain, the RPs serves specific IPv6 multicast groups. Multiple RPs
can coexist in a network. Make sure the RP information on all routers is exactly the same, and a
specific group is mapped to the same RP. Otherwise, IPv6 multicast will fail.
• In the case of the static RP mechanism, the same RP address must be configured on all the routers
in the entire network, including static RPs, by means of the static RP command. Otherwise, IPv6
multicast will fail.
Solution
1. Use the display ipv6 routing-table command to verify that a route to the RP is available on each
router.
2. Use the display pim ipv6 rp-info command to verify that the dynamic RP information is consistent
on all routers. In case of inconsistent RP information, configure consistent RP address on all the
routers.
3. Use the display pim ipv6 rp-info command to verify that the same RP address has been configured
on all the routers throughout the network.