PIM SM configuration and optimal RPs placement

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Hello, everybody,

could you please give me some advices for optimal PIM SM configuration. There is a topology map below.


From Source Server (SCCM) in VLAN Z OS images should be deployed to PCs in VLANs A,B,C,D,E. The customer wants to use PIM in Sparse Mode. 

What are the most appropriate switches for RP and CBSR placement? What a configuration should I apply to X670? Now I have:

enable igmp
enable igmp snooping

enable ipmcforwarding VLAN-A
enable ipmcforwarding VLAN-B
enable ipmcforwarding VLAN-C
enable ipmcforwarding VLAN-D
enable ipmcforwarding VLAN-E
enable ipmcforwarding VLAN-Z

configure pim add vlan VLAN-A
configure pim add vlan VLAN-B
configure pim add vlan VLAN-C
configure pim add vlan VLAN-D
configure pim add vlan VLAN-E
configure pim add vlan VLAN-Z

configure pim crp VLAN-A rp_list
configure pim crp VLAN-B rp_list
configure pim crp VLAN-C rp_list
configure pim crp VLAN-D rp_list
configure pim crp VLAN-E rp_list
configure pim crp VLAN-Z rp_list

configure pim cbsr VLAN-A
configure pim cbsr VLAN-B
configure pim cbsr VLAN-C
configure pim cbsr VLAN-D
configure pim cbsr VLAN-E
configure pim cbsr VLAN-Z

enable pim

igmp snooping is enables on all switches on the topology. Here are my rp_list.pol file:

entry rp_list {
if match any {
then {

The problem is inter-VLAN multicast doesn't work. Where should I start?

At the moment C3560 and X670 sees each other as neighbors:

x670# sh pim vlan "Default"
    PIM SPARSE Interface[1] on VLAN Default is enabled and up
    IP adr:    mask:    DR of the net:
    DR Priority               : 1
    Passive                   : No
    Hello Interval            : 30 sec
    Neighbor Time out         : 105 sec
    Join/Prune Interval       : 60 sec
    Join/Prune holdtime       : 210 sec
    Trusted Gateway           : none
    CRP group List            : rpset with priority 192
    Shutdown priority         : 1024
    Source Specific Multicast : Disabled
    State Refresh             : Off
    State Refresh Capable     : No
    Border                    : No
                             Generation             State     DR
    Neighbor IP address      Id           Expires   Refresh   Priority             0x6c479da        91   No               1

    Packet Statistics (In/Out)
    Hellos             797        77562   Bootstraps           0          394
    Join/Prunes          0            0   Asserts              0            0
    Grafts               0            0   GraftAcks            0            0
    State Refresh        0            0


But I can't see Huawei CX110 as neighbor from X670 for a while...

Many thanks in advance,
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Ilya Semenov

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Posted 8 months ago

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Sarah Seidl

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Our computer techs image across vlans, we use pim sparse too

Here's the pim config from our core, we create a loopback  (and we make sure we... enable loopback-mode vlan hxloop)
We configure the cbsr for that loopback

configure pim add vlan "hxloop" sparse
configure pim crp vlan "HXloop" "RP-list" 30
configure pim add vlan "IDF1" sparse
configure pim add vlan "IDF2" sparse
configure pim add vlan "MDF" sparse
enable pim
configure pim cbsr vlan "HXloop"

Our RP-list looks this way:

entry rp-list {
        if match any{
        then {

 # sh pim
PIM Enabled, Version 2
PIM CRP Enabled on 1 interfaces
BSR state           : ELECTED ; BSR Hash Mask :