Allied Telesis AR400 manual Page 54 AlliedWare OS How To Note IGMP

Static IGMP > Explanation of Static IGMP

We can see the static entry on switch 3 by checking the IGMP snooping and IGMP tables.

Manager Switch 3> show igmpsnooping

IGMP Snooping

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

Status		Enabled
Disabled All-groups ports		........ None
Vlan	Name (vlan id) ..... default (1)
Fast	Leave	Off
Group List
No	group memberships.
Vlan	Name (vlan id) ..... vlan100 (100)
Fast	Leave	Off
Group List
Group. 224.12.13.14		Entry timeout Infinity
Ports 5

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

Manager Switch 3> show ip igmp

IGMP Protocol

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

Status	Enabled
Default Query Interval	125	secs
Default Timeout Interval	260	secs
Last Member Query Interval	10 (1/10secs)
Last Member Query Count	2
Robustness Variable	2
Query Response Interval	100	(1/10secs)
Disabled All-groups ports	None

Interface Name	vlan100	(DR)
IGMP Proxy	Off
Group List
Group. 224.12.13.14	Static association	Refresh time Infinity
Ports 5
Static Ports 5

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

Note that switch 3—the Querier—has no entry for port 26 and therefore does not send the multicast to switch 1. This is because the static entry joined switch 1 to the stream without any client sending a Membership Report.

If the multicast server was attached to switch 3 instead of switch 1, we would have to change switch 3’s configuration. We would need to add a static entry for the port that switch 3 uses to connect to switch 1 (port 26). Although this is unnecessary in this scenario, we will do it to demonstrate the effect, by using the following commands.

Page 54 AlliedWare™ OS How To Note: IGMP