(Revised 2013-06-21)
47
Example of an IGMP info screen
(without cycling power, <ESCAPE>, SWITCH, IGMP, INFO):
CLI\SWITCH\IGMP>info
IGMP Snooping is ENABLED. When power is cycled:
Query mode is auto.
Query Frame Source IP: 191.23.12.15.
Received Lower Query Frame Source IP: 10.10.10.5.
For IGMP Snooping, router ports mode is auto.
Manually Selected Router Port(s): 3 17
Automatically detected Router Port(s): 4 5
Rfilter is applied to these ports: 5 8 17
These ports receive General Broadcast now: 1
There is a total of 1 Static Filter Active.
There is more info. Press 'SPACE BAR' to continue, or escape to exit.
There are a total of 3 Multicast Groups Active.
Address Member Port(s)
------------------------- -----------------------------------------------------------
224.129.1.10 1 6 7
01-00-5E-0A-0B-0C 2 7 19 22 (static filter 1)
226.129.1.11 2 3 4
CLI\SWITCH\IGMP>
In the example above:
The lower source IP query that was received is identified.
Ports 3 and 17 were manually chosen as router (switch link) ports.
(
One does not have to manually enter anything
, unless accommodating non-IGMP devices.)
Ports 4 and 5 were automatically detected as router (switch link) ports.
Rfilter was applied for ports 5, 8, and 17.
o
Ports 5 and 17 were receiving IGMP control, but not igmp group data.
o
Ports 3 and 4 were receiving IGMP control AND igmp group data.
o
‘rfilter’ on for port 8 will have had no impact, as it was not a router port.
(
One does not have to manually enter anything,
unless desiring to limit data to some router ports.)
There was one manually entered ‘static’ multicast group active (described below - ‘sfilter’).
(
One does not have to manually enter anything
, unless accommodating non-IGMP devices,
or ‘filtering’ for other reasons.)
There were two dynamically formed (with ‘joins’) igmp groups active.
As an example, incoming data frames with a destination address of 01-00-5E-0A-0A-0B were sent to ports
1, 6, and 7 as group members and to ports 3 and 4 as ‘router’ ports without rfilter set. Any joins or leaves
were being sent to ports 3, 4, 5, and 17 as ‘router’ (switch link) ports.
