MLS-RP Hello Multicast Messages

[kfarrington]

All,

The MLS-RP sends hello's to the CMGP mcast address every 15 secs.

All downstream switches in the network recv these hello messages.

I have 2 6500s with a dot1q trunk and an MSFC in both. MLS enabled by default. Sniffing the trunk and i would expect to see an MLS hello packet every 15 secs addressed to 01-00-0c-dd-dd-dd (CGMP address), but I dont see it.

Please help.

[briapolo]

you know, I have wondered about this for some time also. I have never been able to see those guys on my sniffer. May be I am doing soemthing wrong.

[DALE FRANCIS]

I would not expect to see these packets unless the MLS-RP is defined as external and thus not in the same Chassis.

MLS flow do not flow across switches the flows that one see's within the sh mls entry are local to the device and only that device.

In order to see these hello's i think on would have to configure and external MLS-RP on the MLS-SE

[kfarrington]

Dale, Thx for ur help fella :)

All, Here is the MLS-RP hello packet sniffed from an external MLS-RP.

Frame 2 (110 on wire, 110 captured)

Arrival Time: Dec 12, 2002 11:12:48.700621000

Time delta from previous packet: 0.176623000 seconds

Time relative to first packet: 0.176623000 seconds

Frame Number: 2

Packet Length: 110 bytes

Capture Length: 110 bytes

IEEE 802.3 Ethernet

Destination: 01:00:0c:dd:dd:dd (01:00:0c:dd:dd:dd)

Source: 00:0a:8a:a8:e0:a2 (00:0a:8a:a8:e0:a2)

Length: 96

Logical-Link Control

DSAP: SNAP (0xaa)

IG Bit: Individual

SSAP: SNAP (0xaa)

CR Bit: Command

Control field: U, func = UI (0x03)

000. 00.. = Unnumbered Information

.... ..11 = Unnumbered frame

Organization Code: Cisco (0x00000c)

Protocol ID: 0x0105

Data (88 bytes)

0000 01 01 00 58 04 03 0c 00 54 65 73 74 00 00 00 00 ...X....Test....

0010 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

0020 00 00 00 00 00 00 00 00 c0 a8 c4 11 00 0a 8a a8 ................

0030 e0 a0 40 00 b2 37 9a ef 00 01 00 01 00 01 00 0e ..@..7..........

0040 00 0a 8a a8 e0 a2 20 00 00 02 00 06 00 0e 00 0a ...... .........

0050 8a a8 e0 a2 30 00 00 02 ....0...