Users Guide

Table Of Contents
Enable IGMP snooping globally using the ip igmp snooping enable command in CONFIGURATION mode. This
command enables IGMP snooping on all VLAN interfaces.
NOTE: You cannot enable IGMP or MLD snooping when configuring VLAN scale profile. If you enable VLAN scale profile,
OS10 disables IGMP and MLD snooping globally. When you disable VLAN scale profile configuration, you must explicitly
enable IGMP and MLD snooping globally.
(Optional) Disable IGMP snooping on specific VLAN interfaces using the no ip igmp snooping command in VLAN
INTERFACE mode.
(Optional) Multicast flood control is enabled by default. To disable the multicast flood restrict feature, use the no
multicast snooping flood-restrict command in CONFIGURATION mode. To reenable the feature globally, use
the multicast snooping flood-restrict command in CONFIGURATION mode.
In a network, the snooping switch is connected to a multicast Router that sends IGMP queries. On a Layer 2 network that
does not have a multicast router, you can configure the snooping switch to act as querier. Use the ip igmp snooping
querier command in VLAN INTERFACE mode to send the queries.
OS10 learns the multicast router interface dynamically based on the interface on which IGMP membership query is received.
To assign a multicast router interface statically, use the ip igmp snooping mrouter interface interfacetype
command in VLAN INTERFACE mode.
NOTE:
IGMP snooping dynamically detects the mrouter interface based on IGMP queries that it receives. If there are more
than one multicast routers connected to the snooping switch, one of them will send IGMP queries and the interface
connected to that router is dynamically learnt as an mrouter port. You must configure the interfaces connected to other
multicast routers as static mrouter port.
(Optional) Configure the IGMP version using the ip igmp version version-number command in VLAN INTERFACE
mode.
(Optional) The fast leave option allows the IGMP snooping switch to remove an interface from the multicast group
immediately on receiving the leave message. Enable fast leave with the ip igmp snooping fast-leave command
in VLAN INTERFACE mode.
(Optional) Configure the time interval for sending IGMP general queries with the ip igmp snooping query-interval
query-interval-time command in VLAN INTERFACE mode.
(Optional) Configure the maximum time for responding to a query advertised in IGMP queries using the ip igmp
snooping query-max-resp-time query-response-time command in VLAN INTERFACE mode.
(Optional) Configures the time interval between group-specific IGMP query messages with the ip igmp snooping
last-member-query-interval query-interval-time command in VLAN INTERFACE mode.
IGMP snooping configuration
OS10(config)# ip igmp snooping enable
OS10(config)# interface vlan 100
OS10(conf-if-vl-100)# ip igmp snooping mrouter interface ethernet 1/1/32
OS10(conf-if-vl-100)# ip igmp snooping querier
OS10(conf-if-vl-100)# ip igmp version 3
OS10(conf-if-vl-100)# ip igmp snooping fast-leave
OS10(conf-if-vl-100)# ip igmp snooping query-interval 60
OS10(conf-if-vl-100)# ip igmp snooping query-max-resp-time 10
OS10(conf-if-vl-100)# ip igmp snooping last-member-query-interval 1000
View IGMP snooping information
OS10# show ip igmp snooping groups
Total Number of Groups: 480
IGMP Connected Group Membership
Group Address Interface Mode Expires
225.1.0.0 vlan3531 IGMPv2-Compat 00:01:35
Member-ports :port-channel41,ethernet1/1/51,ethernet1/1/52
225.1.0.1 vlan3531 IGMPv2-Compat 00:01:35
Member-ports :port-channel41,ethernet1/1/51,ethernet1/1/52
225.1.0.2 vlan3531 IGMPv2-Compat 00:01:35
Member-ports :port-channel41,ethernet1/1/51,ethernet1/1/52
225.1.0.3 vlan3531 IGMPv2-Compat 00:01:35
Member-ports :port-channel41,ethernet1/1/51,ethernet1/1/52
225.1.0.4 vlan3531 IGMPv2-Compat 00:01:35
Member-ports :port-channel41,ethernet1/1/51,ethernet1/1/52
225.1.0.5 vlan3531 IGMPv2-Compat 00:01:35
Member-ports :port-channel41,ethernet1/1/51,ethernet1/1/52
225.1.0.6 vlan3531 IGMPv2-Compat 00:01:35
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Multicast