Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. If you'd prefer to explore, try our test area to get started. And see here for current known issues.

New Member

igmp snooping only for Some multicast group ?

hello

on 6500 series only Multicast group 224.X.X.X work with Igmp snooping

if i try IGMP snooping with Multicast Group 228.X.X.X it do not work

is it a know issue or restrictions ?

thanks in advance for any comments

JYP

11 REPLIES

Re: igmp snooping only for Some multicast group ?

IGMP snooping configurations, doesnt involve, specification of MCast group information.

ip igmp snooping vlan mrouter learn {cgmp | pim-dvmrp} -- this is the command to enable igmp snooping.

If this is not working for the 228.x.x.x, you might want to try statically adding a layer 2 port as member of a group.

ip igmp snooping vlan static interface

In this command,

is the vlan to the multicast group 228.x.x.x belong

is the mac address of multicast group.

is the member port on the switch.

By entering multiple commands, you can make more than one interface, part of the same multicast group.

New Member

Re: igmp snooping only for Some multicast group ?

thanks for you reply, but my problem is more simple

my configuration is:

Vlan 2==6500==trunk=6500=trunk==6500=vlan 2

all 6500 have igmp snooping enable

i send multicast flow 224.X.X.X on left 6500 switch's port in vlan 2

and received this flow on all ports belong same vlan (Vlan 2) on all

6500s.(right one in my picture)

now if i send multicast flow 228.X.X.X on left 6500 switch's port in vlan 2

i didnt received this flow on all ports belong same vlan (Vlan 2) on all

6500s( right one in my picture).

is it a normal behavior ?

thanks in advance for any comments

JYP

Re: igmp snooping only for Some multicast group ?

Can you try using a different group say 227.x.x.x ...just for testing...

New Member

Re: igmp snooping only for Some multicast group ?

unfortunatly not, program doing multicast stream work only with 224 and 228

JYP

Bronze

Re: igmp snooping only for Some multicast group ?

JEANYVES,

What 224.x.x.x group address are you sending to? Are there any group members (receivers) in your scenario, or are you just trying to test igmp snooping?

-Zach

New Member

Re: igmp snooping only for Some multicast group ?

Zach

i use 224.0.0.35 and 228.8.8.8 and have one sender and 2 receivers (just

for tests on customer's site it will be more than 100 receivers)

i have also a network sniffer and see 228.8.8.8 streams are not propagated if

igmp snooping is enabled.

jean-yves

Bronze

Re: igmp snooping only for Some multicast group ?

Jeanyves,

Multicast addresses within the 224.0.0.0-224.0.0.255 range are reserved for use by network protocols (OSPF, EIGRP, IGMP, etc.). They are referred to as link local in scope, as they are never forwarded by routers. Addresses within this range are never pruned by IGMP snooping. This means that the behavior you are seeing is normal.

-Zach

New Member

Re: igmp snooping only for Some multicast group ?

Zach

in fact for my test 224.0.0.8 work with igmp but,228.X.X.X i didnt received

this multicast when i use 228.X.X.X and igmp snooping enable

jean-yves

Bronze

Re: igmp snooping only for Some multicast group ?

The behavior *should* be:

Multicast frames destined for group address 224.0.0.8 will be flooded out all switch ports within the same VLAN. Multicast frames destined for group address 228.x.x.x will only be forwarded out switch ports where an IGMP Membership Report has been received for that group.

Are you seeing something different?

-Zach

New Member

Re: igmp snooping only for Some multicast group ?

Are you seeing something different?

yes 224.0.0.X are flooded out

228.X.X.X are not forwarded even if IGMP Membership report has been sent

jean-yves

Bronze

Re: igmp snooping only for Some multicast group ?

The 244.x.x.x should be flooded out - that's good. For 228.8.8.8, do you see MAC address 01-00-5E-08-08-08 in the cam table ('sh cam sta')? Do you see 01-00-5E-00-00-01 in the 'sh cam sys' output? You can also check IGMP stats with the command 'sh igmp stat'.

565
Views
0
Helpful
11
Replies