Solved: Muticast question:Is "RP" detected via autorp?

news2010a · ‎07-06-2009

Hi, can you clarify this;when I do on my L3 switch:

'show ip pim autorp' I do not see any rp listed.

Then if I do 'show ip pim rp' I see rp's listed.

On the respective L3 switch, I do not see any rp listed manually.

Question:How are RP's being detected in this case? If it is via 'autoRP', why the command show ip pim autorp does not show any rp listed then?

switch1#show ip pim bsr-router

PIMv2 Bootstrap information

switch1#show ip pim rp

Group: 239.254.3.11 **

Group: 239.254.3.3

Group: 239.254.34.4

Group: 239.254.3.23

Group: 239.254.34.3

** note:edited numbers.

switch1#show ip pim autorp

AutoRP Information:

AutoRP is enabled.

PIM AutoRP Statistics: Sent/Received

RP Announce: 0/0, RP Discovery: 0/0

switch1#

This is the configuration on the L3 switches. I do not see any mention of manual RP configuration.

(...)

ip muticast-routing distributed

ip multicast multipath

ip multicast rpf interval 1

ip multicast rpf backoff 100 100

ip igmp ssm-map enable

ip igmp ssm-map static list 9.3.3.5

(...)

Edison Ortiz · ‎07-07-2009

That's correct. Pay close attention to the Flags on the right.

'sTI' means the Mcast groups are running on SSM

You also notice, there aren't any *,G joins as the receivers are sending S,G joins since they know which source they want to receive the Mcast data from.

HTH,

__

Edison.

View solution in original post

Edison Ortiz · ‎07-06-2009

Based on the portion of your config, you are using SSM (Source Specific Multicast), thus the sources and receivers know where to go hence no need for RP.

If you post the 'show ip mroute' more information regarding the groups can be illustrated.

HTH,

__

Edison.

andrew.butterworth · ‎07-06-2009

Try the command 'show ip pim rp mapping'. This should show you what RP's are handling what multicast groups and how this mapping was learned - i.e. static config, auto-rp or bsr.

HTH

Andy

news2010a · ‎07-06-2009

Here it is. I noticed that 'show ip pim rp map' did not list anything. So it means there are no RP's, since we are using static sm, correct?

l3-switch#show ip pim rp map

PIM Group-to-RP Mappings

l3-switch#show ip mroute

IP Multicast Routing Table

Flags: D - Dense, S - Sparse, B - Bidir Group, s - SSM Group, C - Connected,

L - Local, P - Pruned, R - RP-bit set, F - Register flag,

!** output supressed for simplicity

Outgoing interface flags: H - Hardware switched, A - Assert winner

Timers: Uptime/Expires

Interface state: Interface, Next-Hop or VCD, State/Mode

(10.1.37.2, 239.254.13.33), 4w4d/00:02:59, flags: sTI

Incoming interface: GigabitEthernet1/0/3, RPF nbr 10.1.40.17

Outgoing interface list:

Vlan306, Forward/Sparse, 4w4d/00:02:48

(10.1.37.3, 239.254.13.12), 4w4d/00:02:59, flags: sTI

Incoming interface: GigabitEthernet1/0/2, RPF nbr 10.1.40.17

Outgoing interface list:

Vlan306, Forward/Sparse, 3w4d/00:02:41

(...)

Edison Ortiz · ‎07-07-2009

That's correct. Pay close attention to the Flags on the right.

'sTI' means the Mcast groups are running on SSM

You also notice, there aren't any *,G joins as the receivers are sending S,G joins since they know which source they want to receive the Mcast data from.

HTH,

__

Edison.