When a client joins a group – Allied Telesis AR400 User Manual
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Multiple potential IGMP queriers > Explanation of Multiple potential IGMP queriers
When a client joins a group
Now imagine that Client 1 sends a Membership Report to switch 2 for the group
224.12.13.14. If we check the group membership for switch 2 by using the command show
igmpsnooping, we see a group entry for 224.12.13.14.
If we check the group membership for switches 1 and 3, we see no entries for 224.12.13.14,
but see an All Groups entry on each switch. The All Groups entry points to the Querier,
switch 2. The output for switch 1, for example, shows port 49 as the All Groups port,
indicating that switch 1 reaches the Querier via port 49.
Note:
An All Groups port does not necessarily indicate that an IGMP Querier can be found
via that port—it could be a router instead. See
"Controlling which addresses create
All Groups entries" on page 95
Manager Switch 2> 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 225 secs
Ports 2
------------------------------------------------------------------------
Manager Switch 1> 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 25 secs
Ports None
All Groups Entry timeout 177 secs
Ports 49
------------------------------------------------------------------------