Multicast MoH (MMoH) with IGMP Snooping

If you decide to enable MMoH on LAN, by default MMoH streams will flood your LAN for all VLANs. Multicasting is unlike broadcast (per-VLAN). Instead it is flooded out of all ports regardless of their VLAN membership. One way of resolving this is using IGMP Snooping. This example shows the process of IP Phone joining IGMP group to start receiving MMoH while IGMP Snooping Enabled.

Prerequisites

1. Enable IGMP Snooping (enabled by default on all new switches)
2. Enable IGMP Querier on the Root Switch. Note: You need to enable IGMP Querier for one time to trigger IGMP Snooping learning process (the process of mapping ports to IGMP Group Addresses).

Setup Details

• MMoH server IP is 239.1.1.11
• Phone IP is 10.170.4.149
• VLAN number 104
• Port Number Te3/1

Debugs

!!! ..... Call Placed on Hold

Jan  8 2015 13:59:06.748 UAE: IGMPSN: Received IGMPv2 Report for group 239.1.1.11 received on Vlan 104, port Te3/1

Jan  8 2015 13:59:06.748 UAE: IGMPSN: group: Received IGMPv2 report for group 239.1.1.11 received on Vlan 104, port Te3/1

Jan  8 2015 13:59:06.748 UAE: IGMPSN: group: Adding client ip 10.170.4.149, port_id Te3/1, on vlan 104

!!! ..... Create IGMP Group on the Switch

Jan  8 2015 13:59:06.748 UAE: IGMPSN: MCAST IP address 239.1.1.11, MAC address 0100.5e01.010b

Jan  8 2015 13:59:06.748 UAE: IGMPSN: Can not Locate gce 0100.5e01.010b, on Vlan 104

Jan  8 2015 13:59:06.748 UAE: IGMPSN: MCAST IP address 239.1.1.11, MAC address 0100.5e01.010b

Jan  8 2015 13:59:06.748 UAE: IGMPSN: Can not Locate gce 0100.5e01.010b, on Vlan 104

Jan  8 2015 13:59:06.748 UAE: IGMPSN: mgt: created gce 0100.5e01.010b, on Vlan 104

Jan  8 2015 13:59:06.748 UAE: l2mcm_group_create: creating a group 239.1.1.11 on vlan 104, dummy NO

Jan  8 2015 13:59:06.748 UAE: l2mcm_group_create: timer stop: vlan 104, group 239.1.1.11

Jan  8 2015 13:59:06.748 UAE: IGMPSN: mgt: created group 239.1.1.11, on Vlan 104

Jan  8 2015 13:59:06.748 UAE: IGMPSN: group: Created group 239.1.1.11

!!! ..... IGMP Port Learning Process

Jan  8 2015 13:59:06.748 UAE: IGMPSN: Add v2 group 239.1.1.11 member port Te3/1, on Vlan 104

Jan  8 2015 13:59:06.748 UAE: IGMPSN: mgt: Vlan 104 gce 0100.5e01.010b add port Te3/1

Jan  8 2015 13:59:06.748 UAE: L2MM: setting Te3/1 in gce->mbr_blist

Jan  8 2015 13:59:06.748 UAE: IGMPSN: group: Added port Te3/1 to group 239.1.1.11

Jan  8 2015 13:59:06.748 UAE: l2mcsn_process_report: TIMER_START for group 35.201.180.0 for time 10000 * 100

Jan  8 2015 13:59:06.748 UAE: IGMPSN: group: Forwarding 239.1.1.11 report to router ports

Jan  8 2015 13:59:26.641 UAE: l2mcsn_gquery_gce_walk: TIMER_STOP for group 239.1.1.11

!!! ..... Keepalive IGMP Messages

Jan  8 2015 13:59:36.121 UAE: IGMPSN: Received IGMPv2 Report for group 239.1.1.11 received on Vlan 104, port Te3/1

Jan  8 2015 13:59:36.121 UAE: IGMPSN: group: Received IGMPv2 report for group 239.1.1.11 received on Vlan 104, port Te3/1

Jan  8 2015 13:59:36.121 UAE: IGMPSN: group: Skip client info adding - ip 10.170.4.149, port_id Te3/1, on vlan 104

Jan  8 2015 13:59:36.121 UAE: IGMPSN: MCAST IP address 239.1.1.11, MAC address 0100.5e01.010b

Jan  8 2015 13:59:36.121 UAE: IGMPSN:  Locate gce 0100.5e01.010b, on Vlan 104

Jan  8 2015 13:59:36.121 UAE: IGMPSN:  locate group 239.1.1.11, on Vlan 104

Jan  8 2015 13:59:36.121 UAE: IGMPSN: Add v2 group 239.1.1.11 member port Te3/1, on Vlan 104

Jan  8 2015 13:59:36.125 UAE: IGMPSN: group: Added port Te3/1 to group 239.1.1.11

Jan  8 2015 13:59:36.125 UAE: l2mcsn_process_report: TIMER_START for group 35.201.180.0 for time 10000 * 100

Jan  8 2015 13:59:36.125 UAE: IGMPSN: group: Forwarding 239.1.1.11 report to router ports

!!! ….. IGMP Report Message

Jan  8 2015 13:59:41.113 UAE: IGMPSN: sync group for group (239.1.1.11) blist (0)

Jan  8 2015 13:59:41.113 UAE: IGMPSN: timer: Vlan 104 report timer expired

Jan  8 2015 13:59:41.113 UAE: IGMPSN: sync group for Vlan 104 robustness variable 3

Jan  8 2015 13:59:41.113 UAE: IGMPSN: sync group for Vlan 104 GCE 0100.5e01.010b

Jan  8 2015 13:59:41.113 UAE: IGMPSN: sync group for group (239.1.1.11) blist (0)

Jan  8 2015 13:59:41.113 UAE: IGMPSN: group (239.1.1.11): has v2 Hosts

Jan  8 2015 13:59:41.113 UAE: IGMPSN: group (239.1.1.11): [0]GQ-miss-list members are:

Jan  8 2015 13:59:41.113 UAE: IGMPSN: group (239.1.1.11): [1]GQ-miss-list members are:

Jan  8 2015 13:59:41.113 UAE: IGMPSN: group (239.1.1.11): [2]GQ-miss-list members are:

Before Call on Hold

4507-sw0l#sh ip igmp snooping groups

Vlan      Group                    Version     Port List

----------------------------------------------------------------------

100       239.0.0.10               v2          Gi1/37, Gi1/39, Gi1/40,

                                               Gi1/43, Gi1/44, Gi2/43,

                                               Te3/1

100       224.0.1.60               v2          Te3/1

100       239.255.255.250          v2          Gi1/2, Gi1/3, Gi1/6,

                                               Gi1/8, Gi1/10, Gi1/11,

                                               Gi1/12, Gi1/13, Gi1/14,

                                               Gi1/15, Gi1/16, Gi1/17,

                                               Gi1/18, Gi1/19, Gi1/20,

                                               Gi1/22, Gi1/28, Gi1/32,

                                               Gi1/33, Gi2/1, Gi2/2,

                                               Gi2/3, Gi2/5, Gi2/7,

                                               Gi2/8, Gi2/11, Gi2/12,

                                               Gi2/14, Gi2/17, Gi2/18,

                                               Gi2/27, Gi2/34, Gi2/35,

                                               Te3/1, Gi5/7, Gi5/9,

                                               Gi5/22, Gi5/23, Gi5/28

102       239.192.152.143          v2          Te3/1

102       239.255.255.250          v2          Te3/1

102       239.255.255.253          v2          Te3/1

107       239.255.255.250          v2          Te3/1

After Call on Hold

4507-sw0l#sh ip igmp snooping groups

Vlan      Group                    Version     Port List

----------------------------------------------------------------------

100       239.0.0.10               v2          Gi1/37, Gi1/39, Gi1/40,

                                               Gi1/43, Gi1/44, Gi2/43,

                                               Te3/1

100       224.0.1.60               v2          Te3/1

100       239.255.255.250          v2          Gi1/2, Gi1/3, Gi1/6,

                                               Gi1/8, Gi1/10, Gi1/11,

                                               Gi1/12, Gi1/13, Gi1/14,

                                               Gi1/15, Gi1/16, Gi1/17,

                                               Gi1/18, Gi1/19, Gi1/20,

                                               Gi1/22, Gi1/28, Gi1/32,

                                               Gi1/33, Gi2/1, Gi2/2,

                                               Gi2/3, Gi2/5, Gi2/7,

                                               Gi2/8, Gi2/11, Gi2/12,

                                               Gi2/14, Gi2/17, Gi2/18,

                                               Gi2/27, Gi2/34, Gi2/35,

                                               Te3/1, Gi5/7, Gi5/9,

                                               Gi5/22, Gi5/23, Gi5/28

102       239.192.152.143          v2          Te3/1

102       239.255.255.250          v2          Te3/1

102       239.255.255.253          v2          Te3/1

104       239.1.1.11               v2          Te3/1

107       239.255.255.250          v2          Te3/1