[j-nsp] multicast questions
Stacy W. Smith
stacy at acm.org
Tue Apr 20 19:55:38 EDT 2010
This is the expected PIM join state at the RP if the receiver's DR has not yet joined the S,G.
Your previous output of "show multicast extensive" shows that the PR router was forwarding (or at least attempting to forward) traffic over the RPT. Your outputs from hs1 showed that it was not receiving the traffic over the RPT, and was therefore not joining the SPT.
Seems we need to figure out why the traffic being forwarded over the RPT from PR is not being received by hs1.
--Stacy
On Apr 20, 2010, at 3:16 PM, snort bsd wrote:
> from the PR, it seems that receiver's DR connecting to PR:
>
> ------------------------------------------------
> user at PR# 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 <---
> 10.100.2.9 State: Join Flags: SRW Timeout: 177
>
> 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: 309
> <--- no downstream neighbor
> Instance: PIM.master Family: INET6
> --------------------------------------------------------------
>
> It seems that the first "Group: 225.0.0.1" was from receiver's DR and the second "Group: 225.0.0.1" was from the source.
>
> But receiver's DR doesn't seem to be aware of this:
>
> ----------------------------------------
> 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
> -----------------------------------------------------------------
>
> Am I missing something?
>
>
>
> --- On Wed, 21/4/10, snort bsd <snortbsd at yahoo.com.au> wrote:
>
>> From: snort bsd <snortbsd at yahoo.com.au>
>> Subject: Re: [j-nsp] multicast questions
>> To: "juniper-nsp" <juniper-nsp at puck.nether.net>, "Nilesh Khambal" <nkhambal at juniper.net>
>> Received: Wednesday, 21 April, 2010, 5:34 AM
>> 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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>> https://puck.nether.net/mailman/listinfo/juniper-nsp
>>
>
>
>
>
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