[j-nsp] multicast questions

Stacy W. Smith stacy at acm.org
Tue Apr 20 16:04:59 EDT 2010


Are PR and hs1 directly connected to each other via PR so-0/1/1.0 to hs1 so-0/1/0.0? Can you try checking counters using "monitor interface <if>" on each side and confirm that the traffic is really being sent out so-0/1/1.0 on PR and really being received by so-0/1/0.0 on hs1?

I'd also be interested in seeing the output of "show pim statistics" and "show route forwarding-table multicast extensive destination 225.0.0.1" on both PR and hs1.

--Stacy


On Apr 20, 2010, at 1:34 PM, snort bsd wrote:

> Thanks.
> 
> I think the source and PR are connected:
> 
> ------------------------------------------
> user at PR# run show multicast route extensive
> Family: INET
> 
> Group: 225.0.0.1
>    Source: 10.0.5.200/32                             <---
>    Upstream interface: fe-0/0/2.0                    <---
>    Downstream interface list: 
>        so-0/1/1.0                                    <---
>    Session description: MALLOC   
>    Statistics: 18 kBps, 200 pps, 1001490 packets
>    Next-hop ID: 262151
>    Upstream protocol: PIM
>    Route state: Active
>    Forwarding state: Forwarding
>    Cache lifetime/timeout: 360 seconds
>    Wrong incoming interface notifications: 0
> 
> Family: INET6
> 
> user at PR# run show pim rps extensive  
> Instance: PIM.master
> Address family INET
> 
> RP: 10.100.3.4
> Learned from 10.100.2.9 via: bootstrap
> Time Active: 19:35:16
> Holdtime: 150 with 97 remaining
> Device Index: 138
> Subunit: 32769
> Interface: pd-1/2/0.32769
> Group Ranges:
>        224.0.0.0/4
> Active groups using RP:
>        225.0.0.1                     <----
> 
>        total 2 groups active
> Register State for RP:
> Group           Source          FirstHop        RP Address      State    Timeout
> 225.0.0.1       10.100.5.200      10.100.6.2        10.100.3.4        Receive      258
> 
> RP: 10.100.3.4
> Learned via: static configuration
> Time Active: 19:37:51
> Holdtime: 0
> Device Index: 138
> Subunit: 32769
> Interface: pd-1/2/0.32769
> Group Ranges:
>        224.0.0.0/4
> 
> Address family INET6
> ---------------------------------------------
> 
> For the simplicity, I have only one router "hs1" on the receiver segment:
> 
> -----------------------------------------------
> user at hs1# run show pim interfaces 
> Instance: PIM.master
> 
> Name                   Stat Mode       IP V State Count DR address
> at-0/2/1.50            Up   Sparse      4 2 P2P       1
> fe-1/3/0.0             Up   Sparse      4 2 DR        0 172.20.30.1  <--
> pe-1/2/0.32769         Up   Sparse      4 2 P2P       0
> pe-1/2/0.32770         Up   Sparse      4 2 P2P       0
> so-0/1/0.0             Up   Sparse      4 2 P2P       1
> 
> user at hs1# run show igmp group 225.0.0.1 detail 
> Interface: fe-1/3/0.0
>    Group: 225.0.0.1
>        Source: 0.0.0.0                      <---
>        Last reported by: 172.16.30.2        <---
>        Timeout:     182 Type: Dynamic       <---
> 
> user at hs1# run show pim rps extensive            
> Instance: PIM.master
> Address family INET
> 
> RP: 10.100.3.4                               <---
> Learned from 10.100.3.4 via: bootstrap
> Time Active: 19:06:49
> Holdtime: 150 with 107 remaining
> Device Index: 137
> Subunit: 32769
> Interface: pe-1/2/0.32769
> Group Ranges:
>        224.0.0.0/4
> Active groups using RP:
>        225.0.0.1                        <---
> 
>        total 2 groups active
> 
> Address family INET6
> 
> user at hs1# run show multicast rpf 10.100.5.200 
> Multicast RPF table: inet.0 , 78 entries
> 
> 10.100.5.0/24                            <---
>    Protocol: IS-IS
>    Interface: so-0/1/0.0
>    Neighbor: 10.100.2.10
> -------------------------------------------------
> 
> As Stacy pointed out, the receiver's DR doesn't seem to connect to PR via RPT:
> 
> -------------------------------------------------------
> user at hs1# run show pim join extensive             
> Instance: PIM.master Family: INET
> 
> Group: 225.0.0.1
>    Source: *                                   <---
>    RP: 10.100.3.4
>    Flags: sparse,rptree,wildcard               <---
>    Upstream interface: so-0/1/0.0            
>    Upstream neighbor: 10.100.2.10
>    Upstream state: Join to RP
>    Downstream neighbors:
>        Interface: fe-1/3/0.0                   <---
>            172.20.30.1 State: Join Flags: SRW  Timeout: Infinity
> 
> Instance: PIM.master Family: INET6
> 
> user at hs1# run show multicast route extensive      
> Family: INET
> 
> Family: INET6
> -------------------------------------------------------
> 
> Thanks.
> 
> --- On Tue, 20/4/10, Nilesh Khambal <nkhambal at juniper.net> wrote:
> 
>> From: Nilesh Khambal <nkhambal at juniper.net>
>> Subject: Re: [j-nsp] multicast questions
>> To: "snort bsd" <snortbsd at yahoo.com.au>, "juniper-nsp" <juniper-nsp at puck.nether.net>
>> Received: Tuesday, 20 April, 2010, 6:08 PM
>> Do you know if Source is registered
>> with the RP? SPT flag is set on (S,G) on
>> the RP so it must have but just in case check "show pim rps
>> extensive" on
>> both source DR and RP. Does the SPT path from receiver DR
>> to the Source DR
>> goes via RP or does it take an alternate path?
>> 
>> One more thing to check is, are there more than one PIM
>> routers on the
>> receiver segments. Only the PIM DR on the segment would
>> generate (S,G) join
>> towards the source. Check "show pim interface" for the
>> receiver segment.
>> 
>> Also, check if Receiver DR can find rpf path towards the
>> source DR to send
>> (S,G) join. Try "show multicast rpf <src DR IP>" on
>> the receiver DR to check
>> this.
>> 
>> Thanks,
>> Nilesh.
>> 
>> 
>> On 4/19/10 5:02 PM, "snort bsd" <snortbsd at yahoo.com.au>
>> wrote:
>> 
>>> Hi all:
>>> 
>>> I have an active multicast receiver looking for source
>> 225.0.0.1:
>>> 
>>> -----------------------------------------------------
>>> user at hs3# run show pim join extensive
>>> Instance: PIM.master Family: INET
>>> 
>>> Group: 225.0.0.1
>>>      Source: *
>>>      RP: 10.100.3.4
>>>      Flags: sparse,rptree,wildcard
>>>      Upstream interface:
>> so-0/1/0.0
>>>      Upstream neighbor:
>> 10.100.2.10
>>>      Upstream state: Join to RP
>>>      Downstream neighbors:
>>>          Interface:
>> fe-1/3/0.0
>>>          
>>    172.20.30.1 State: Join Flags: SRW 
>> Timeout: Infinity
>>> 
>>>                
>>                
>>          <-------- Nothing
>> here.
>>> 
>>> Instance: PIM.master Family: INET6
>>> ------------------------------------------------
>>> 
>>> from above data, it doesn't seem to find the source.
>> but I took a look at RPS:
>>> 
>>> 
>> -----------------------------------------------------------
>>> user at RP# run show pim join extensive
>>> Instance: PIM.master Family: INET
>>> 
>>> Group: 225.0.0.1
>>>      Source: *
>>>      RP: 10.100.3.4
>>>      Flags: sparse,rptree,wildcard
>>>      Upstream interface: Local
>>>      Upstream neighbor: Local
>>>      Upstream state: Local RP
>>>      Downstream neighbors:
>>>          Interface:
>> so-0/1/1.0
>>>          
>>    10.1000.2.9 State: Join Flags: SRW
>> Timeout: 191
>>> 
>>> Group: 225.0.0.1
>>>      Source: 10.100.5.200
>>>      Flags: sparse,spt
>>>      Upstream interface:
>> fe-0/0/2.0
>>>      Upstream neighbor:
>> 10.100.4.18
>>>      Upstream state: Local RP, Join
>> to Source
>>>      Keepalive timeout: 32 
>>          
>>    <----- No downstream neighbor
>>> 
>>> Instance: PIM.master Family: INET6
>>> -----------------------------------------------------
>>> 
>>> It seems that RP knows the source of group 225.0.0.1
>> but somehow the source
>>> and receiver just won't connect. Somehow RP doesn't
>> work?
>>> 
>>> here is the RP config:
>>> 
>>> user at RR# show protocols pim
>>> rp {
>>>      bootstrap-priority 10;
>>>      local {
>>>          address
>> 10.100.3.4;
>>>      }
>>> }
>>> interface fe-0/0/0.0 {
>>>      mode sparse;
>>> }
>>> interface fe-0/0/1.0 {
>>>      mode sparse;
>>> }
>>> interface fe-0/0/2.0 {
>>>      mode sparse;
>>> }
>>> interface fe-0/0/3.0 {
>>>      mode sparse;
>>> }
>>> interface so-0/1/0.100 {
>>>      mode sparse;
>>> }
>>> interface so-0/1/1.0 {
>>>      mode sparse;
>>> }
>>> 
>>> 
>>> any ideas?
>>> 
>>> 
>>> 
>>> 
>>> 
>>>        
>>> 
>>> _______________________________________________
>>> juniper-nsp mailing list juniper-nsp at puck.nether.net
>>> https://puck.nether.net/mailman/listinfo/juniper-nsp
>> 
>> 
> 
> 
> 




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