Service Manual

Version Description
7.7.1.0 Introduced on the E-Series.
Example
Dell# show ip igmp ssm-map
Interface Vlan 20
Group 232.1.1.5
Uptime 00:11:22
Expires Never
Router mode INCLUDE
Last reporter 35.0.0.2
Group source list
Source address Expires
65.0.0.1 00:01:22
65.0.0.2 00:01:22
65.0.0.3 00:01:22
65.0.0.4 00:01:22
65.0.0.5 00:01:22
Related Commands
• ip igmp ssm-map — use a statically congured list to translate (*,G) memberships to (S,G) memberships.
IGMP Snooping Commands
Dell Networking OS supports IGMP Snooping version 2 and 3 on all Dell Networking systems.
Important Points to Remember for IGMP Snooping
• Dell Networking OS supports version 1, version 2, and version 3 hosts.
• Dell Networking OS 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 ow table not in Layer 2 forwarding information base (FIB).
• Dell Networking OS IGMP snooping implementation is based on draft-ietf-magma-snoop-10.
• Dell Networking OS 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 a default VLAN interface.
• IGMP snooping is not supported over VLAN-Stack-enabled VLAN interfaces (you must disable IGMP snooping on a VLAN interface
before conguring VLAN-Stack-related commands).
• IGMP snooping does not react to Layer 2 topology changes triggered by spanning tree protocol (STP).
• IGMP snooping reacts to Layer 2 topology changes multiple spanning tree protocol (MSTP) triggers by sending a general query on the
interface that comes in the FWD state.
Important Points to Remember for IGMP Querier
• The IGMP snooping Querier supports version 2.
• You must congure 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 reassigned to the VLAN interface.
• When enabled, IGMP snooping Querier does not start if there is a statically congured 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 checks the IP source address of the incoming frame.
Internet Group Management Protocol (IGMP)
663