Multicast Issue

kian_hong2000 · ‎01-22-2009

Say i have enable ip multicast-routing on Switch A, B and C. Switch B is a core switch. Next i put in the commands on Switch A, B and C

Connection link

PC C > SwC > SwB > SwA > PC A

SwA (Distribution Switch)

int gi1/1 to SwB

channel-group 2 mode on

Vlan A

ip pim sparse-dense-mode

no ip route-cache cef

ip cgmp

no ip mroute-cache

Port Channel 2 to SwB

ip pim sparse-dense-mode

ip cgmp

SwB (Core)

int gi1/1 To SwA

switchport

switchport access vlan B1

switchport mode access

no ip address

vlan B1

ip pim sparse-dense-mode

ip cgmp

int gi1/2 to SwC

switchport

switchport access vlan B2

switchport mode access

no ip address

vlan B2

ip pim sparse-dense-mode

ip cgmp

SwC (Server farm)

int gi1/1 to SwB

switchport access vlan C

switchport mode access

Vlan C

ip pim sparse-dense-mode

no ip route-cache cef

ip cgmp

no ip mroute-cache

Then I insert PC A to Switch A port and from PC C to Switch C port.

I do a ping from PC A to PC C and it work. However, if i use iperf, i am not able to capture the multicast packets from PC A to PC C

Does fast-switching cache affect multicast to be enable in the network?

mchin345 · ‎01-29-2009

Complete these steps to determine if the source is actually sourcing the packets and inserting the correct packet fields:

1. Check the interface counters on the host. First, check the interface counters (if you are on a UNIX system, use the netstat command) on the source host to see if it is sending packets. If it is not, check for misconfiguration or bugs in the host stack and application.

2. Use the show ip igmp groups interface-name command to check the upstream router to see if it received a join membership report at the interface directly connected to source.

Here is the link for Basic Multicast Troubleshooting Tools.

http://www.cisco.com/en/US/tech/tk828/technologies_tech_note09186a0080093f21.shtml#sourcepacket