[j-nsp] multicast questions

snort bsd snortbsd at yahoo.com.au
Tue Apr 20 15:34:36 EDT 2010


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
> 
> 


      



More information about the juniper-nsp mailing list