This command shuts down the complete snooping configuration in the Switch. When the user does not require the IGMP snooping module to be running, it can be shut down. When shut down, all resources acquired by the Snooping Module are released to the system. For the IGS feature to be functional on the Switch, the system-control status must be set as start and the state must be enabled.

The no form of the command starts and enables snooping in the Switch.

Snooping cannot be started in the Switch if the base bridge mode is configured as transparent bridging.

shutdown snooping

no shutdown snooping

This command specifies the snooping multicast forwarding mode (IP based or MAC based).

snooping multicast-forwarding-mode {ip | mac}

• ip - Configures the multicast forwarding mode as IP Address based. The PIM queries the IGS module to obtain the Portlist.

• mac - Configures the multicast forwarding mode as MAC Address based. The PIM queries the VLAN to obtain the Portlist.

This command enables IGMP snooping in the Switch, globally or on a specific VLAN. When snooping is enabled in a Switch or interface, it learns the hosts intention to listen to a specific multicast address. When the Switch receives any packet from the specified multicast address, it forwards the packet to the host listening for that address. Broadcasting is avoided to save bandwidth. When IGMP snooping is enabled globally, it is enabled in all the existing VLAN interfaces.

The no form of the command disables IGMP snooping in the Switch, globally or on a specific VLAN. When IGMP snooping is disabled globally, it is disabled in all the existing VLAN interfaces.

Global Configuration Mode

ip igmp snooping [vlan < vlan–id >]

no ip igmp snooping [vlan < vlan–id >]

Config-VLAN Mode

ip igmp snooping

no ip igmp snooping

• <vlan –id> - VLAN ID is a unique value that represents the specific VLAN. This value ranges between 1 and 4094.

This command sets the IGMP snooping router port purge time- out interval. Snooping learns the available router ports and initiates router port purge time-out timer for each learnt router port. The routers send control messages to the ports. If the router ports receive such control messages, the timer is restarted. If no message is received by the router ports before the timer expires, the router port entry is purged. The purge time-out value ranges between 60 and 600 seconds.

This command is a standardized implementation of the existing command; ip igmp snooping mrouter-time-out. It operates similar to the existing command.

ip igmp querier-timeout <(60 - 600) seconds>

This command enables fast leave processing and IGMP snooping for a specific VLAN, It enables IGMP snooping only for the specific VLAN when IGMP snooping is globally disabled. When the fast leave feature is enabled, port information is removed from a multicast group entry immediately after fast leave message is received. The ID of the VLAN ranges between 1 and 4094.

The no form of the command disables fast leave processing for a specific VLAN.

This command is a standardized implementation of the existing command; ip igmp snooping fast-leave. It operates similar to the existing command.

Fast leave configurations done in a VLAN when IGMP snooping is disabled in a VLAN, will be applied only when IGMP snooping is enabled in the VLAN.

ip igmp snooping vlan <vlanid(1-4094)> immediate-leave

no ip igmp snooping vlan <vlanid(1-4094)> immediate-leave

This command enables IGMP snooping and configures a list of multicast router ports for a specific VLAN, if IGMP snooping is globally enabled. This will enable IGMP snooping only for the specific VLAN, if IGMP snooping is globally disabled.

Any IGMP message received on a Switch is forwarded only on the router-ports and not on host ports. In this manner, the IGMP

snooping functionality avoids flooding of IGMP query messages from the host to the entire network.

The no form of the command deletes the statically configured router ports for a VLAN.

This command is a standardized implementation of the existing command; ip igmp snooping mrouter. It operates similar to the existing command.

The list of multicast router ports configured while IGMP snooping is disabled in the VLAN is applied only when the IGMP snooping is enabled in the VLAN.

ip igmp snooping vlan <vlanid (1-4094)> mrouter < interface- type > <0/a-b, 0/c, ...>

no ip igmp snooping vlan <vlanid (1-4094)> mrouter < interface- type > <0/a-b, 0/c, ...>

• <vlanid (1-4094)> - Configures the VLAN for which the list of multicast router ports should be configured statically. This is a unique value that represents the specific L3 VLAN created. An L3 VLAN interface is a VLAN that is mapped to an IP interface and assigned an IP address. This value ranges between 1 and 4094.

• < interface-type > - Configures the list of multicast router ports for the specified type of interface. The interface can be:

  • gigabitethernet - A version of LAN standard architecture that supports data transfer upto 1 Gigabit per second.

  • port-channel - Logical interface that represents an aggregator which contains several ports aggregated together.

• <0/a-b, 0/c, ...> - Sets the list of multicast router ports for the list of interfaces or a specific interface identifier. This value is a combination of slot number and port number separated by a slash. Port-channel ID is provided, for interface type port-channel. Use comma as a separator without space while configuring list of interfaces. Example: 0/1, 0/3 or 1, 3.

This command sets the IGMP snooping report-suppression time interval. The Switch forwards IGMPv2 report message to the multicast group. A timer is started immediately after forwarding the report message and runs for set period of time. During this interval the Switch does not forward another IGMPv2 report message addressed to the same multicast group to the router ports.

The no form of the command sets the IGMP snooping report- suppression interval time to the default value.

The ip igmp snooping report-suppression-interval is used only when the proxy and proxy-reporting are disabled.

ip igmp snooping report-suppression-interval <(1 – 25) seconds>

no ip igmp snooping report-suppression-interval

This command sets the time interval after which the Switch sends a group specific query to find out if there are any interested receivers in the group when it receives a leave message. If it does not receive a response from the group, the port is removed from the group membership information in the forwarding database. This value ranges between 2 and 5.

The no form of the commands sets the group specific query interval time to default value.

ip igmp snooping group-query-interval <2-5) seconds>

no ip igmp snooping group-query-interval

This command configures the operating version of the IGMP snooping Switch for a specific VLAN. The version can be set manually to execute condition specific commands.

ip igmp snooping version { v1 |v2 | v3}

• v1 - Configures the version as IGMP snooping Version 1.
• v2 - Configures the version IGMP snooping Version 2.
• v3 - Configures the version IGMP snooping Version 3.

This command enables fast leave processing and IGMP snooping for a specific VLAN, It enables IGMP snooping only for the specific VLAN when IGMP snooping is globally disabled.

When the fast leave feature is enabled, port information is removed from a multicast group entry immediately after fast leave message is received.

The no form of the command disables fast leave processing for a specific VLAN.

Fast leave configurations done in a VLAN when IGMP snooping is disabled in a VLAN, will be applied only when IGMP snooping is enabled in the VLAN.

ip igmp snooping fast-leave

no ip igmp snooping fast-leave

This commands configures the IGMP snooping Switch as a querier for a specific VLAN. When configured as a querier, the Switch sends IGMP query messages. The query messages will be suppressed if there are any routers in the network.

The no form of the command configures the IGMP snooping Switch as non-querier for a specific VLAN.

ip igmp snooping querier

no ip igmp snooping querier

This command sets the time interval at which the IGMP snooping queries are sent by the Switch when configured as querier on a VLAN. The value range is between 60 to 600 seconds.

The no form of the command sets the IGMP querier interval to default value.

The Switch must be configured as a querier for this configuration to be imposed.

ip igmp snooping query-interval <(60 - 600) seconds>

no ip igmp snooping query-interval

This command sets the time interval between the IGMP snooping query messages sent by the Switch, during startup of the querier election process. This time interval ranges between 15 and 150 seconds and should be less than or equal to query interval divided by four.

The no form of the command sets the IGMP startup query interval to the default value.

The Switch should be configured as querier for the startup query interval command to produce results.

The startup query interval should be less than or equal to ¼ of the query interval.

ip igmp snooping startup-query-interval <(15 - 150) seconds>

no ip igmp snooping startup-query-interval

This command sets the maximum number of general query messages sent out on Switch startup when the Switch is configured as a querier. This value ranges between two and five. Startup query messages are sent to announce the presence of the Switch along with its identity. The startup query count is manually configured to change the existing count. This value ranges between 2 and 5.The no form of the command sets the number of general query messages sent out on Switch startup when the Switch is configured as a querier to default value.

The Switch should be configured as a querier for startup query count configuration to be effective.

ip igmp snooping startup-query-count <2 - 5>

no ip igmp snooping startup-query-count

This command sets the maximum response code inserted in general queries sent to host. The unit of the reponse code is tenth of second. This value ranges between 0 and 255.

The no form of the command sets the query response code to default value.

ip igmp snooping max-response-code <(0 - 255)>

no ip igmp snooping max-response-code

This command configures a static router-port as blocked router port.

The no form of the command resets the blocked router ports to normal router port.

The ports to be configured as blocked router ports, must not be configured as static router ports.

ip igmp snooping blocked-router <interface-type> <0/a-b, 0/c, ...>

no ip igmp snooping blocked-router <interface-type> <0/a-b, 0/c, ...>

• <interface-type> - Clears all port-level spanning-tree statistics information for the specified type of interface. The interface can be:

  • gigabitethernet - A version of LAN standard architecture that supports data transfer upto 1 Gigabit per second.

  • port-channel - Logical interface that represents an aggregator which contains several ports aggregated together.

• <0/a-b, 0/c, ...> - Sets the list of multicast router ports for the list of interfaces or a specific interface identifier. This value is a combination of slot number and port number separated by a slash. Port-channel ID is provided, for interface type port-channel. Use comma as a separator without space while configuring list of interfaces. Example: 0/1, 0/3 or 1, 3.

This command displays the router ports for all VLANs or a specific VLAN for a given Switch or for all the Switches (if no Switch is specified). The interface details and the corresponding port number along with its type (static/dynamic are displayed.

show ip igmp snooping mrouter [Vlan <vlan-id >] [detail] [switch <switch_name>]

• < vlan-id (1-4094)> - VLAN ID is a unique value that represents the specific VLAN. This value ranges between 1 and 4094

• detail - Displays detailed information about the router ports

• switch <switch_name> - Displays the router ports for the specified context. This value represents unique name of the Switch context. This value is a string whose maximum size is 32. This parameter is specific to multiple instance feature.

This command displays the blocked router ports for all VLANs or a specific VLAN for a given Switch or for all the Switches (if no Switch is specified).

show ip igmp snooping blocked-router [Vlan <vlan-id >] [switch <switch_name>]

• < vlan-id (1-4094)> - VLAN ID is a unique value that represents the specific VLAN. This value ranges between 1 and 4094

• switch <switch_name> - Displays the blocked router ports for specified context. This value represents unique name of the Switch context. This value is a string whose maximum size is 32. This parameter is specific to multiple instance feature.

This command displays IGMP snooping information for all VLANs or a specific VLAN for a given Switch or for all Switches (if Switch is not specified).

show ip igmp snooping globals [switch <switch_name>]

• switch <switch_name> - Displays the specified context. This value represents unique name of the Switch context. This value is a string whose maximum size is 32. This parameter is specific to multiple instance feature.

This command displays IGMP snooping information for all VLANs or a specific VLAN for a given context or for all the context (if no Switch is specified).

show ip igmp snooping [Vlan <vlan-id >] [switch <switch_name>]

• < vlan-id (1-4094)> - VLAN ID is a unique value that represents the specific VLAN. This value ranges between 1 and 4094

• switch <switch_name> - Displays the specified context. This value represents unique name of the Switch context. This value is a string whose maximum size is 32. This parameter is specific to multiple instance feature.

This command displays IGMP group information for all VLANs or a specific VLAN or specific VLAN and group address for a given Switch or for all Switches (if no Switch is specified).

show ip igmp snooping groups [Vlan <vlan-id > [Group <Address>]]

• < vlan-id (1-4094)> - VLAN ID is a unique value that represents the specific VLAN. This value ranges between 1 and 4094

• Group <Address> - Displays the Group Address of the VLAN ID

show ip igmp snooping forwarding-database

show ip igmp snooping forwarding-database [Vlan <vlan-id>]

• < vlan-id (1-4094)> - VLAN ID is a unique value that represents the specific VLAN. This value ranges between 1 and 4094

• Group <Address> - Displays the Group Address of the VLAN ID

This command displays IGMP snooping statistics for all VLANs or a specific VLAN for a given Switch or for all Switches (if no Switch is specified).

show ip igmp snooping statistics [Vlan <vlan-id >] [switch <switch_name>]

• < vlan-id (1-4094)> - VLAN ID is a unique value that represents the specific VLAN. This value ranges between 1 and 4094

• switch <switch_name> - Displays the specified context. This value represents unique name of the Switch context. This value is a string whose maximum size is 32. This parameter is specific to multiple instance feature.

This command displays multicast VLAN statistics in a Switch and displays various profiles mapped to the multicast VLANs.

show ip igmp snooping multicast-vlan [switch <switch_name>]

• switch <switch_name> - Displays the specified context. This value represents unique name of the Switch context. This value is a string whose maximum size is 32. This parameter is specific to multiple instance feature.