HP 5500 Ei 5500 Si Switch Series Configuration Guide

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Step Command Remarks 
3.  Configure the maximum 
number of downstream nodes 
for a single IPv6 multicast 
forwarding entry.  multicast ipv6 forwarding-table 
downstream-limit 
limit  Optional. 
128 by default. 
 
Displaying and maintaining IPv6 multicast routing 
and forwarding 
 
Task Command Remarks 
Display the IPv6 multicast boundary 
information.  display multicast ipv6 boundary 
{ group  
[  ipv6-group-address  [ prefix-length ] ] | scope 
[ scope-id  ] } [ interface  interface-type...

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Task Command Remarks 
Clear routing entries from the IPv6 
multicast routing table. reset multicast ipv6 routing-table
 
{ { ipv6-source-address  [ prefix-length ] | 
ipv6-group-address  [ prefix-length ] | 
incoming-interface  { interface-type 
interface-number  | register  } } * | all  }  Available in user 
view
 
 
For more information about designated forwarder (DF), see  Configuring IPv6 PIM (available only on the 
HP 5
500 EI) . 
 
 IMPORTANT: 
The 
reset  command clears the information in...

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source-policy command so that the source IP address of the IPv6 multicast packets and the IPv6 
multicast group address can both match the IPv6 ACL rule.   

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Configuring MLD (available only on the HP 
5500 EI) 
Overview 
An IPv6 router uses the Multicast Listener Discovery (MLD) protocol to discover the presence of multicast 
listeners on the directly attached subnets. Multicast listeners are nodes that want to receive IPv6 multicast 
packets. 
Through MLD, the router can determine whether any IPv6 multicast listeners exist on the directly 
connected subnets, put corresponding records in the database, and maintain timers related to IPv6 
multicast...

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2.
 
After receiving a general query, every MLD router  compares the source IPv6 address of the query 
message with its own interface address. After com parison, the router with the lowest IPv6 address 
wins the querier election and all ot her routers become non-queriers.  
3. All the non-queriers start a timer called the other querier present timer. If a router receives an 
MLD query from the querier before the timer expires,  it resets this timer. Otherwise, it assumes that 
the querier has timed...

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6.
 
When the IPv6 multicast data addres sed to G1 or G2 reaches an MLD router, because the (*, G1) 
and (*, G2) multicast forwarding entries exist on  the MLD router, the router forwards the IPv6 
multicast data to the local subnet, and then the receivers on the subnet receive the data.  
Leaving an IPv6 multicast group 
When a host leaves a multicast group, the following occur:  
1.  The host sends an MLD done message to all IPv6 multicast routers on the local subnet. The 
destination address is...

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Figure 82 Flow paths of multicast-address-and- source-specific multicast traffic 
 
 
In the case of MLDv1, Host B cannot select IPv6 multicast sources when it joins IPv6 multicast group G. 
Therefore, IPv6 multicast streams from both Source 1 and Source 2 will flow to Host B whether it needs 
them or not.   
When MLDv2 is running on the hosts and routers, Host B can explicitly express its interest in the IPv6 
multicast data that Source 1 sends to G (denoted as  (S1, G)), rather than the IPv6...

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Figure 83 MLDv2 query message format 
 
 
Table 9 MLDv2 query message field description 
Field Descri
ption 
Type = 130   Message type. For a query message, this field is set to 130.
 
Code  Initialized to zero.
 
Checksum
  Standard IPv6 checksum.
 
Maximum Response Delay  Maximum response delay allowed before a host sends a report message.
Reserved
  Reserved field and initialized to zero.
 
Multicast Address 
• This field is set to 0 in a general query message. 
• It is set to a specific IPv6...

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Field Description 
Number of Sources 
• This field is set to 0 in a general query message or a 
multicast-address-specific query message. 
• This field represents the number of source addresses in a 
multicast-address-and-source-specific query message.  
Source Address( i )
 IPv6 multicast source address in a multicast-address-specific query 
message (i = 1, 2, .., n, where n represents the number of multicast source 
addresses.)
 
 
MLD report message 
A host sends an MLD report message to repo rt...

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MLD SSM mapping 
The MLD SSM mapping feature enables you to configure static MLD SSM mappings on the last hop router 
to provide SSM support for receiver hosts that are running MLDv1. The SSM model assumes that the last 
hop router has identified the desired IPv6 multicast sources when receivers join IPv6 multicast groups. 
•  W h e n  a n  M L D v 2  e n a b l e d  h o s t  j o i n s  a  m u l t i c a s t  g r o u p ,  i t  c a n  e x p l i c i t l y  s p e c i f y  o n e  o r  m o r e  m u l t...