HP 5500 Ei 5500 Si Switch Series Configuration Guide

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To solve the issues, PIM-SM allows an RP or the DR at the receiver side to initiate an SPT switchover 
process. 
1. The RP initiates an SPT switchover process. 
The RP can periodically check the passing-by IPv4 mu lticast packets. If it finds that the traffic rate 
exceeds a configurable threshold, the RP sends an  (S, G) join message hop by hop toward the 
multicast source to establish an SPT between the  DR at the source side and the RP. Subsequent 
multicast data travels along the established...

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RP discovery 
BIDIR-PIM uses the same RP discovery mechanism as PIM-SM does. For more information, see  RP 
dis
covery . 
In PIM-SM, an RP must be specified with a real IP address. In BIDIR-PIM, however, an RP can be specified 
with a virtual IP address, which is called the rendez vous point address (RPA). The link corresponding to 
the RPA’s subnet is called the rendezvous point link (R PL). All interfaces connected to the RPL can act as 
the RP, and they back up one another.  
 
  NOTE: 
In...

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4.
 
In the case of a tie in the metric, the  router with the highest IP address wins.  
Bidirectional RPT building 
A bidirectional RPT comprises a receiver-side RPT and a source-side RPT. The receiver-side RPT is rooted 
at the RP and takes the routers directly connected to the receivers as leaves. The source-side RPT is also 
rooted at the RP but takes the routers directly connected to the sources as leaves. The processes for 
building these two parts are different.  
Figure 45 RPT building at...

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Figure 46 RPT building at the multicast source side 
 
 
As shown in Figure 46, the pr ocess for building a source-side RPT is relatively simple:  
4. When a multicast source sends multicast packets  to multicast group G, the DF in each network 
segment unconditionally forwards the packets to the RP.  
5.  The routers along the path from the source’s directly  c o n n e c t e d  r o u t e r  t o  t h e  R P  f o r m  a n  R P T  b r a n c h .  
Each router on this branch adds a (*, G) entry to  its...

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Admin-scope zones are divided specific to multicast groups. Zone border routers (ZBRs) form the 
boundary of the admin-scope zone. Each admin-scope zone maintains one BSR, which serves multicast 
groups within a specific range. Multicast protocol packets, such as assert messages and bootstrap 
messages, for a specific group range cannot cros s the admin-scope zone boundary. Multicast group 
ranges that different admin-scope zones serve can be overlapped. A multicast group is valid only within 
its...

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Figure 48 Relationship between admin-scope zones and the global scope zone in group address 
ranges 
 
 
In Figure 48 , the grou p address ranges of admin-scope 1  and 2 have no intersection, whereas the 
group address range of admin-scope 3 is a subset  of the address range of admin-scope 1. The 
group address range of the global scope zone cove rs all the group addresses other than those of 
all the admin-scope zones. That is, the group addre ss range of the global scope zone is G-G1-G2. 
In...

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SPT building 
The decision to build an RPT for PIM-SM or an SPT for PIM-SSM depends on whether the multicast group 
the receiver will join falls into the SSM group range (SSM group range reserved by IANA is 
232.0.0.0/8).  
Figure 49 SPT building in PIM-SSM  
 
 
As shown in Figure 49, Host B and Host C are multicast information receivers. They send IGMPv3 report 
messages to the respective DRs to express their interest in the information about the specific multicast 
source S. 
After receiving a...

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Figure 50 Relationships among PIM protocols 
 
 
For more information about IGMP SSM mapping, see Configuring IGMP (available only on the HP 
5
500 EI).  
PIM support for VPNs 
To support PIM for VPNs, a multicast router that runs  PIM maintains an independent set of PIM neighbor 
table, multicast routing table, BSR information, and RP-set information for each VPN. 
After receiving a multicast data packet, the multicas t router checks which VPN the data packet belongs 
to, and then forwards the...

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Task  Remarks 
Enabling PIM-DM  Required
 
Enabling state-refresh capability  Optional
 
Configuring state-refresh parameters  Optional
 
Configuring PIM-DM graft retry period  Optional
 
Configuring PIM common features  Optional
 
 
Configuration prerequisites 
Before you configure PIM-DM, complete the following tasks:  
•  Configure any unicast routing protocol so that a ll devices in the domain are interoperable at the 
network layer. 
•   Determine the interval between state-refresh messages....

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Step Command  Description  
3.  Configure an RD for the VPN 
instance.  route-distinguisher 
route-distinguisher
  Not configured by default. 
4.
  Enable IP multicast routing. 
multicast routing-enable  Disabled by default.  
5.  Enter interface view.  interface 
interface-type 
interface-number   N/A 
6.
  Bind the interface with a VPN 
instance.  ip binding vpn-instance
 
vpn-instance-name   By default, an interface belongs to 
the public network, and is not 
bound with any VPN instance. 
7....