HP 5500 Ei 5500 Si Switch Series Configuration Guide

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   Require-router-alert: disabled 
# Display MLD group information on Switch A. 
[SwitchA] display mld group 
Total 1 MLD Group(s). 
Interface group report information 
 Vlan-interface100(2001::1): 
  Total 1 MLD Groups reported 
   Group Address   Last Reporter   Uptime      Expires 
   ff3e::101       2001::2         00:02:04    00:01:15 
The output shows that the MLD reports sent from the hosts are forwarded to Switch A through the 
proxy interface, VLAN-interface 100 of Switch B....

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Inconsistent memberships on routers on the same subnet 
Symptom 
Different memberships are maintained on different MLD routers on the same subnet. 
Analysis 
•  A router running MLD maintains multiple paramet ers for each interface, and these parameters 
influence one another, forming very complicated relationships. Inconsistent MLD interface 
parameter configurations for routers on the same  subnet will surely result in inconsistent MLD 
memberships. 
•   Two MLD versions are available. Although...

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Configuring IPv6 PIM (available only on the HP 
5500 EI) 
Overview 
Protocol Independent Multicast for IPv6 (IPv6 PIM) provi d e s  I P v 6  m u l t i c a s t  f o r w a r d i n g  by  l e ve r a g i n g  I P v 6  
unicast static routes or IPv6 unicast routing tables  generated by any IPv6 unicast routing protocol, such 
as RIPng, OSPFv3, IS-ISv6, or BGP4+. IPv6 PIM uses an IPv6 unicast routing table to perform reverse 
path forwarding (RPF) check to implement IPv6 mult icast forwarding....

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In general, the IPv6 multicast forwarding path is a source tree. That is, it is a forwarding tree with the IPv6 
multicast source as its root and IPv6 multicast group members as its leaves. Because the source tree 
is the shortest path from the IPv6 multicast source to the receivers, it is also called shortest path tree 
(SPT).  
The working mechanism of IPv6 PIM-DM is summarized as follows:  
•  Neighbor discovery 
•   SPT establishment 
•   Graft 
•   Assert 
Neighbor discovery 
In an IPv6 PIM...

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Figure 90 SPT establishment in an IPv6 PIM-DM domain 
 
 
The flood-and-prune process takes place periodically. A pruned state timeout mechanism is provided. A 
pruned branch restarts multicast forwarding when th e pruned state times out and then is pruned again 
when it no longer has any multicast receiver.  
 
  NOTE: 
Pruning has a similar implementation in IPv6 PIM-SM. 
 
Graft 
When a host attached to a pruned node joins an IPv6  multicast group, to reduce the join latency, IPv6 
PIM-DM uses...

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Figure 91 Assert mechanism 
 
 
As shown in Figure 91, af ter Router A and Router B receive an (S, G) IPv6 multicast packet from the 
upstream node, they both forward the packet to the lo cal subnet. As a result, the downstream node Router 
C receives two identical multicast packets, and both Ro uter A and Router B, on their own local interface, 
receive a duplicate IPv6 multicast packet that the ot her has forwarded. After detecting this condition, 
both routers send an assert message to all IPv6...

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•  When an IPv6 multicast source sends IPv6 multicast streams to an IPv6 multicast group, the 
source-side designated router (DR) first registers the multicast source with the RP by sending register 
messages to the RP by unicast until it receives a register-stop message from the RP. The arrival of a 
register message at the RP triggers the establishment of an SPT. The IPv6 multicast source sends 
subsequent IPv6 multicast packets along the SPT to the RP. After reaching the RP, the IPv6 multicast...

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Figure 92 DR election 
 
 
As shown in Figure 92, the D R election process is as follows:  
1. Routers on the multi-access network send hello messages to one another. The hello messages 
contain the router priority for DR election. The router with the highest DR priority will become the 
DR. 
2. In the case of a tie in the router priority, or if any router in the network does not support carrying 
the DR-election priority in hello messages, the ro uter with the highest IPv6 link-local address will...

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multicast groups and RPs. The BSR then encapsulates the RP-set in the bootstrap messages it periodically 
originates and floods the bootstrap messages  (BSMs) to the entire IPv6 PIM-SM domain. 
Figure 93  BSR and C-RPs 
 
 
Based on the information in the RP-sets, all routers in the network can calculate the location of the 
corresponding RPs based on the following rules:  
1. The C-RP with the highest priority wins.  
2. If all the C-RPs have the same priority, their  hash values are calculated...

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Embedded RP 
The embedded RP mechanism enables a router to resolve the RP address from an IPv6 multicast address 
so that the IPv6 multicast group is mapped to an RP. This RP can take the place of the statically configured 
RP or the RP dynamically calculated based on the BSR mechanism. The DR does not need to identif y the 
RP address beforehand. The specific process is as follows.  
At the receiver side, the following occur:  
1.  A receiver host initiates an MLD report to announce  that it is...