Dell Force10 S55T FTOS Command Line Reference Guide for the S55 System FTOS 8. - Page 438

www.dell.com | support.dell.com IGMP Snooping Commands FTOS supports IGMP Snooping version 2 and 3 on all Dell Force10 systems: • ip igmp snooping enable • ip igmp snooping fast-leave • ip igmp snooping flood • ip igmp snooping last-member-query-interval • ip igmp snooping mrouter • ip igmp snooping querier • show ip igmp snooping mrouter Important Points to Remember for IGMP Snooping • FTOS supports version 1, version 2, and version 3 hosts. • FTOS IGMP snooping implementation is based on IP multicast address (not based on Layer 2 multicast mac-address) and the IGMP snooping entries are in Layer 3 flow table not in Layer 2 FIB. • FTOS IGMP snooping implementation is based on draft-ietf-magma-snoop-10. • FTOS supports IGMP snooping on JUMBO enabled cards. • IGMP snooping is not enabled by default on the switch. • A maximum of 1800 groups and 600 VLAN are supported. • IGMP snooping is not supported on default VLAN interface. • IGMP snooping is not supported over VLAN-Stack-enabled VLAN interfaces (you must disable IGMP snooping on a VLAN interface before configuring VLAN-Stack-related commands). • IGMP snooping does not react to Layer 2 topology changes triggered by STP. • IGMP snooping reacts to Layer 2 topology changes triggered by MSTP by sending a general query on the interface that comes in FWD state. Important Points to Remember for IGMP Querier • The IGMP snooping Querier supports version 2. • You must configure an IP address to the VLAN interface for IGMP snooping Querier to begin. The IGMP snooping Querier disables itself when a VLAN IP address is cleared, and then it restarts itself when an IP address is re-assigned to the VLAN interface. • When enabled, IGMP snooping Querier will not start if there is a statically configured multicast router interface in the VLAN. • When enabled, IGMP snooping Querier starts after one query interval in case no IGMP general query (with IP SA lower than its VLAN IP address) is received on any of its VLAN members. • When enabled, IGMP snooping Querier periodically sends general queries with an IP source address of the VLAN interface. If it receives a general query on any of its VLAN member, it will check the IP source address of the incoming frame. If the IP SA in the incoming IGMP general query frame is lower than the IP address of the VLAN interface, then the switch disables its IGMP snooping Querier functionality. If the IP SA of the incoming IGMP general query is higher than the VLAN IP address, the switch will continue to work as an IGMP snooping Querier. 438 | Internet Group Management Protocol (IGMP)