Supermicro SSE-G24-TG4 User manual

L2 / L3 Switches
Internet Group Management
Protocol (IGMP)
Configuration Guide
Revision 1.0

IGMP Configuration Guide
Supermicro L2/L3 Switches
Configuration Guide
2
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Manual Revision 1.0
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Contents
1 IGMP Configuration Guide .................................................................................................................... 4
1.1 IP Multicast Overview ................................................................................................................... 4
1.2 IGMP Basics ................................................................................................................................... 6
1.3 IGMP Support ................................................................................................................................ 7
1.4 IGMP Defaults ............................................................................................................................... 7
1.5 Enabling IGMP ............................................................................................................................... 7
1.6 IGMP Version ................................................................................................................................ 9
1.7 IGMP query and report ............................................................................................................... 11
1.7.1 Query Interval ..................................................................................................................... 11
1.7.2 Maximum query response time .......................................................................................... 14
1.7.3 Robustness Value ................................................................................................................ 16
1.8 Leaving a Multicast Group .......................................................................................................... 18
1.8.1 Last member Query Interval ............................................................................................... 19
1.8.2 Immediate Leave ................................................................................................................. 21
1.9 Static Multicast Group Membership ........................................................................................... 22
1.10 Disabling IGMP ............................................................................................................................ 25
1.11 IGMP Configuration example ...................................................................................................... 27

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1IGMP Configuration Guide
This document describes the IGMP feature supported in Supermicro Layer 2 / Layer 3 switch products.
The IGMP configurations for the below listed Supermicro switch products are covered.
The majority of this document applies to the Supermicro switch products listed above. In any particular
sub section however, the contents might vary across these switch product models. In those sections the
differences are clearly identified with reference to particular switch product models. If any particular
switch product model is not referenced, the reader can safely assume that the content is applicable to
all the above listed models.
Throughout this document, the common term “switch” refers to any of the above listed
Supermicro switch product models unless a particular switch product model is noted.
1.1 IP Multicast Overview
IP communication may be one of three types:
•Unicast: Host sends packets to a single host
•Broadcast: Host sends packets to all hosts
•Multicast: Host sends packets to a subset of hosts simultaneously
IP multicast routing enables efficient use of network resources for bandwidth intensive services
including video and audio. multicast group is a set of receivers that want to receive a particular data
stream. n IP Multicast Group Address in the range 224.0.0.0 to 239.0.0.0 is selected for receivers in a
Top of Rack Switches
• SSE-G24-TG4
• SSE-G48-TG4
• SSE-X24S
• SSE-X3348S
• SSE-X3348T
Blade Switches
• SBM-GEM-X2C
• SBM-GEM-X2C+
• SBM-GEM-X3S+
• SBM-XEM-X10SM

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multicast group. Senders transmit IP data using the multicast group address as the destination address
to multicast to all group members. Receivers interested in receiving data of a particular group must join
the group by signaling a router/switch on their subnet. IGMP is used as the signaling protocol for
conveying group membership. Network devices along the path from source to receivers forward data
only on those ports leading to the receivers rather than flooding all ports.
Membership in a multicast group is dynamic as hosts can join and leave at any time. There is no
restriction on the location or number of members in a multicast group. In addition, a host can be a
member of more than one multicast group at a time.
Supermicro switches can send and receive multicast traffic by supporting the following multicast
features:
•IGMP: at the access end of the network that processes hosts announcing their participation in a
multicast group(s).
•Multicast Routing Protocol’s (MRP’s): at the enterprise and core of the network for maintaining
the senders/receivers database and forwarding data from senders to receivers.
Figure IGMP-1: IP Multicast Routing
Switch B
Switch A
Hosts
IGMP MRP
Internet
Backbone
MRP

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1.2 IGMP Basics
IGMP is an IPv4 protocol used by hosts to request multicast data for a particular group. switch
performs the IGMP function by:
•Sending IGMP query messages to identify receivers interested in particular multicast group(s).
IGMP queries are sent only by a querier.
•Processing IGMP report messages from hosts in response to the query message from the
querier.
Switches maintain a multicast forwarding table based on the hosts joined for every multicast group and
updates the multicast forwarding table when hosts leave multicast groups.
In Figure IGMP-2, the querier switch sends an IGMP General Query message on the L N. Host1 and
Host2 respond to the query with the IGMP report for G1 Group membership.
Figure IGMP-2: Multicast Forwarding wit IGMP
There are 3 versions of IGMP. The basic differences between the versions are:
IGMP v1: Supports basic query-response mechanism to identify active multicast group(s).
IGMP v2: Extends v1 with features like querier elections, IGMP leaves, group-specific queries and
maximum response time fields.
IGMP v3: In addition to IGMP v1 and IGMPv2 features, provides support for source-specific queries and
reports.
Switch – Non Querier
Switch - Querier
Host 1 Host 3
General Query
General Query
Membership
report for G1
Host 2
Membership
report for G1

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Supermicro switch
es
acts as a querier by default as long as it is
a
m
ulticast
router
with
a
lower IP address on the subnet.
1.3 IGMP Support
Supermicro switches support IGMP for all three IGMP versions (1, 2 and 3).
Supermicro switches support up to 255 multicast groups.
1.4 IGMP efaults
Parameter Default Value
IGMP global status
Disabled
IGMP status in
VL N
Disabled
IGMP version
2
Query interval
125
seconds
Query
m
ax response time
100
seconds
Robustness value
2
Last member query interval
10
seconds
Immediate leave (fast leave)
Disabled
Static
m
ulticast
g
roup
m
embership
None
1.5 Enabling IGMP
IGMP is disabled by default in Supermicro switches.
IGMP must be enabled globally and individually in interfaces.
Follow the steps below to enable IGMP.
Step Command Description
Step 1
configure terminal
Enters the configuration mode.
Step 2
set
ip igmp enable
Enables IGMP globally.
Step 3
interface
<
interface
-
type
>
<
interface
-
id
>
or
interface range <interface-type> <interface-id> ….
Enters the interface
configuration
mode.
interface-type – may be any of the
following:
gigabit ethernet – gi-
extreme-ethernet – ex

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qx
-
ethernet
–
qx
vlan
interface-id is in slot/port format for all
physical interfaces. It may be the VL N
identifier for VL N interfaces.
To configure multiple interfaces, use
the “interface range …” command. To
provide a range use a hypen (-)
between the start and end interface
numbers. E.g.: int range gi 0/1-10
To provide multiple interfaces or
ranges, separate with a comma (,).
E.g.: int range gi 0/1-10, gi 0/20
If multiple interfaces are provided, the
next step will enable IGMP on all these
interfaces.
Note: While configuring IGMP on
physical interfaces (gi, ex, qx), make
sure those interfaces are configured as
layer 3 interfaces using the “no
switchport” command in interface
configuration mode.
Step 4
set
ip igmp
enable
Enables IGMP on
interface
.
Step 5
end
Exits the configuration mode.
Step 6
s ow ip igmp
global
-
config
s ow ip igmp interface <interface-type>
<interface-id>
Displays the IGMP information.
Step 7
write startup
-
config
Optional step
–
saves this IGMP
configuration to be part of the startup
configuration.
The example below shows the commands used to enable IGMP.
Enable IGMP for layer3 VLAN 10
SMIS(config)#configure terminal
SMIS(config)# set ip igmp enable
SMIS(config)#end
SMIS# s ow ip igmp global-config
IGMP is globally enabled

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SMIS(config)#configure terminal
SMIS(config)#interface vlan 10
SMIS(config-if)# set ip igmp enable
SMIS(config-if)#end
SMIS# s ow ip igmp interface
vlan10, line protocol is up
Internet address is 2.2.2.2/8
IGMP is enabled on interface
Current IGMP router version is 2
IGMP query interval is 125 seconds
Last member query response interval is 10 seconds
IGMP max query response time is 100 seconds
Robustness value is 2
IGMP querying router is 2.2.2.2 (this system)
Fast leave is disabled on this interface
No multicast groups joined
1.6 IGMP Version
The IGMP protocol standard has three versions: v1, v2 and v3. Supermicro switches support IGMP for all
three versions. Supermicro IGMP support interoperates with different IGMP versions as defined in the
standard IGMP protocol.
The default IGMP version is v2, which is compatible with IGMP versions 1 and 3.
Supermicro switches provide the flexibility for users to configure different IGMP versions on different
interfaces.
Follow the steps below to change the IGMP version on any interface.
Step Command Description
Step 1
configure terminal
Enters the configuration mode.
Step 2
interface
<
interface
-
type
>
<
interface
-
id
>
or
interface range <interface-type> <interface-id> ….
Enters the interface configuration
mode.
interface-type – may be any of the
following:
gigabit ethernet – gi
extreme-ethernet – ex
qx-ethernet – qx
vlan
interface-id is in slot/port format for all
physical interfaces. It may be the VL N

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identifier for VL N interfaces.
To configure multiple interfaces, use
the “interface range …” command. To
provide a range use a hypen (-)
between the start and end interface
numbers. E.g.: int range gi 0/1-10
To provide multiple interfaces or
ranges, separate with a comma (,).
E.g.: int range gi 0/1-10, gi 0/20
If multiple interfaces are provided, the
next step will enable IGMP on all these
interfaces.
Note: While configuring IGMP on
physical interfaces (gi, ex, qx), make
sure those interfaces are configured as
layer 3 interfaces using “no switchport”
command in interface configuration
mode.
Step 3
ip igmp
version { 1 | 2 |
3}
Configures IGMP version.
Step 5
end
Exits the configuration mode.
Step 6
s ow ip igmp interface
<interface-type>
<interface-id>
Displays the IGMP version information
for the given interface.
Step 7
write startup
-
config
Optional step
–
saves this IGMP
configuration to be part of the startup
configuration.
The
“no ip igmp version”
command
resets the IGMP version to its default value
of
2.
The example below shows the commands used to configure different versions of IGMP.
Configure IGMP version 3 for layer3 VLAN 10.
SMIS# configure terminal
SMIS(config)# interface vlan 10
SMIS(config-if)# ip igmp version 3
SMIS(config-if)# end

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SMIS# s ow ip igmp interface
vlan10, line protocol is up
Internet address is 2.2.2.2/8
IGMP is enabled on the interface
Current IGMP router version is 3
IGMP query interval is 125 seconds
Last member query response interval is 10 seconds
IGMP max query response time is 100 seconds
Robustness value is 2
IGMP querying router is 2.2.2.2 (this system)
Fast leave is disabled on this interface
No multicast groups joined
1.7 IGMP Queries and Reports
When IGMP is enabled in a Supermicro switch, it assumes itself as the querier. s long as the switch
does not receive an IGMP query from another multicast router in the subnet with an IP address lower
than itself, it continues to be the IGMP querier on the subnet. If a Supermicro switch acting as querier
receives a query from another multicast router on the subnet with an IP address lower than itself, then
the switch transitions to a non-querier role and resets a timer based on value of its querier timeout.
Upon expiration of the querier timer, a Supermicro switch transitions to querier again if there are no
queries from the router with lower IP address, otherwise it continues to remain the non-querier on the
subnet.
The querier switch is in charge of sending periodic query messages on the network to determine the
presence of any new hosts. Hosts respond to query message from the querier with IGMP report
messages, which indicate inclusion or exclusion in a particular multicast group address. The querier
consolidates the reports from all hosts and maintains them in an IGMP group table.
There are various parameters that control the query and report messages:
Query Interval: This configures the time interval between transmissions of query messages by the
querier.
Max Response Time: This configures the maximum time interval in which the querier will wait to receive
reports from the hosts
Robustness Value: This parameter tunes certain intervals used in IGMP protocol and also determines
the retransmissions of IGMPv3 report messages to prevent their loss in a network.
1.7.1 Query Interval
The IGMP querier sends IGMP queries periodically to determine if there are any new hosts. This periodic
time interval is called the query interval.
The default query interval is 125 seconds.

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Supermicro switches provide flexibility for users to configure different query interval on different
interfaces.
Follow the steps below to change the query interval on any interface.
Step Command Description
Step 1
configure terminal
Enters the configuration mode.
Step 2
I
nterface
<
interface
-
type
>
<
interface
-
id
>
or
interface range <interface-type> <interface-id> ….
Enters the interface configuration
mode.
interface-type – may be any of the
following:
gigabit ethernet – gi
extreme-ethernet – ex
qx-ethernet – qx
vlan
interface-id is in slot/port format for all
physical interfaces. It may be the VL N
identifier for VL N interfaces.
To configure multiple interfaces, use
the “interface range …” command. To
provide a range use a hypen (-)
between the start and end interface
numbers. E.g.: int range gi 0/1-10
To provide multiple interfaces or
ranges, separate with a comma (,).
E.g.: int range gi 0/1-10, gi 0/20
If multiple interfaces are provided, the
next step will enable IGMP on all these
interfaces.
Note: While configuring IGMP on
physical interfaces (gi, ex, qx), make
sure those interfaces are configured as
layer 3 interfaces using the “no
switchport” command in interface
configuration mode.
Step 3
ip igmp query
-
interval <
value
>
Configures IGMP
query interval
.
The query interval value can be 1-
65535 seconds. Default is 125
seconds.
Step 5
end
Exits the configuration mode.

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Step 6
s ow ip igmp interface
<interface-type>
<interface-id>
Displays the IGMP
query interval
information for the given interface.
Step 7
write startup
-
config
Optional step
–
saves this IGMP
configuration to be part of the startup
configuration.
The
“no ip igmp
query
-
interval
”
command
resets the IGMP
query interval
to i
ts default
value of 125.
The example below shows the commands used to configure the IGMP query interval.
Configure IGMP query interval for layer3 VLAN 10
SMIS(config)#configure terminal
SMIS(config)#interface vlan 10
SMIS(config-if)# ip igmp query-interval 500
SMIS(config-if)# end
SMIS# s ow ip igmp interface
vlan10, line protocol is up
Internet address is 2.2.2.2/8
IGMP is enabled on the interface
Current IGMP router version is 2
IGMP query interval is 500 seconds
Last member query response interval is 10 seconds
IGMP max query response time is 100 seconds
Robustness value is 2
IGMP querying router is 2.2.2.2 (this system)
Fast leave is disabled on this interface
No multicast groups joined
SMIS# s ow ip igmp statistics
IGMP statistics for vlan10
Number of general queries received 0
Number of group specific queries received 0
Number of group and source Specific queries received 0
Number of v1/v2 reports received 0
Number of v3 reports received 0
Number of v2 leaves received 0
Number of general queries transmitted 32
Number of group specific queries transmitted 0
Number of group and source specific queries transmitted 0

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1.7.2 Maximum Query Response Time
For every inclusion report received by the querier, the particular interface entry is added in the IGMP
group table for that particular group. group membership timeout is then started for each
group/interface entry in the IGMP group table. The query response interval is used to calculate the
group membership timeout.
Group membership timeout = (robustness value * query interval) + max query response interval.
Once a query is received by the hosts, they should respond with IGMP reports within the max query
response time. The querier deletes the hosts’ interface entry from the IGMP group table if no reports are
received from the host by the time the group membership timeout is reached.
The default query-max-response time is 100 seconds.
Supermicro switches provide flexibility for users to configure different query-max-response times on
different interfaces.
Follow the steps below to change the query-max-response on any interface.
Step Command Description
Step 1
configure terminal
Enters the configuration mode.
Step 2
interface
<
interface
-
type
>
<
interface
-
id
>
or
interface range <interface-type> <interface-id> ….
Enters the interface configuration
mode.
interface-type – may be any of the
following:
gigabit ethernet – gi
extreme-ethernet – ex
qx-ethernet – qx
vlan
interface-id is in slot/port format for all
physical interfaces. It may be the VL N
identifier for VL N interfaces.
To configure multiple interfaces, use
the “interface range …” command. To
provide a range use a hypen (-)
between the start and end interface
numbers. E.g.: int range gi 0/1-10
To provide multiple interfaces or
ranges, separate with a comma (,).
E.g.: int range gi 0/1-10, gi 0/20
If multiple interfaces are provided, the
next step will enable IGMP on all these

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interfaces.
Note: While configuring IGMP on
physical interfaces (gi, ex, qx), make
sure those interfaces are configured as
layer 3 interfaces using the “no
switchport” command in interface
configuration mode.
Step 3
i
p igmp
query
-
max
-
response
-
time <value
>
Configures IGMP query
-
max
-
response
time.
The value of query-max-response time
is 1-255 seconds. Default is 100
seconds.
Step 5
end
Exits the configuration mode.
Step 6
s ow
ip igmp interface
<interface-type>
<interface-id>
Displays the IGMP
query
-
max
-
response
time information for the given
interface.
Step 7
write startup
-
config
Optional step
–
saves this IGMP
configuration to be part of the startup
configuration.
The
“
no ip igmp
query
-
max
-
response
-
tim
e”
command
resets the query
-
max
-
response
-
time
to its default of 100.
Configure query-max-response times only on the IGMPv2 interface.
The example below shows the commands used to configure IGMP query maximum response time.
Configure IGMP query maximum response time for layer3 VLAN 10
SMIS(config)#configure terminal
SMIS(config)#interface vlan 10
SMIS(config-if)# ip igmp query-max-response-time 255
SMIS(config-if)# end
SMIS# s ow ip igmp interface
vlan10, line protocol is up
Internet address is 2.2.2.2/8
IGMP is enabled on interface
Current IGMP router version is 2
IGMP query interval is 125 seconds
Last member query response interval is 10 seconds
IGMP max query response time is 255 seconds

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Robustness value is 2
IGMP querying router is 2.2.2.2 (this system)
Fast leave is disabled on this interface
No multicast groups joined
1.7.3 Robustness Value
The robustness value can be fine-tuned to allow for expected packet losses on a subnet. The value of
this variable affects certain IGMP message intervals for IGMPv2 and IGMPv3 as specified below:
•Group membership interval: mount of time that must pass before a multicast router
determines that there are no more members of a group on a network.
Group membership interval = (Robustness value * query interval) + query response interval.
•Other querier present interval: The robustness value is used to calculate the amount of time that
must pass before a multicast router determines that there is no longer another multicast router
that is the querier.
Other querier present interval = (Robustness value * query interval) + (0.5 * query response
interval).
•ast-member query count: Number of group-specific queries sent before the router assumes
that there are no local members of a group. The number of queries is equal to the robustness
value.
In IGMPv3, devices send a state-change report whenever the interface state changes. The number of
times a state-change report is retransmitted is equal to the robustness value minus one.
The default robustness value is 2. You should increase this value if the subnet is expected to lose
packets.
Supermicro switches provide flexibility for users to configure different robustness value on different
interfaces.
Follow the steps below to change the robustness value on any interface.
Step Command Description
Step 1
configure terminal
Enters the configuration mode.
Step 2
interface
<
interface
-
type
>
<
interface
-
id
>
or
interface range <interface-type> <interface-id> ….
Enters the interface configuration
mode.
interface-type – may be any of the
following:
gigabit ethernet – gi
extreme-ethernet – ex
qx-ethernet – qx
vlan
interface-id is in slot/port format for all

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physical interfaces. It may be the VL N
identifier for VL N interfaces.
To configure multiple interfaces, use
the “interface range …” command. To
provide a range use a hypen (-)
between the start and end interface
numbers. E.g.: int range gi 0/1-10
To provide multiple interfaces or
ranges, separate with a comma (,).
E.g.: int range gi 0/1-10, gi 0/20
If multiple interfaces are provided, the
next step will enable IGMP on all these
interfaces.
Note: While configuring IGMP on
physical interfaces (gi, ex, qx), make
sure those interfaces are configured as
layer 3 interfaces using the “no
switchport” command in interface
configuration mode.
Step 3
ip igmp robustness <value
>
Configures
the
IGMP
robustness
value
.
The robustness value can be any
number from 1-255 seconds. Default is
2 seconds.
Step 5
end
Exits the configuration mode.
Step 6
s ow ip igmp interface
<interface-type>
<interface-id>
Displays the IGMP
robustness
information for the given interface.
Step 7
write startup
-
config
Optional step
–
saves this IGMP
configuration to be part of the startup
configuration.
The
“
no ip igmp
robustness
”
command
resets the robustness
value to
its
default
value of
2.
Configure the robustness value only on IGMPv2 and IGMPv3 interfaces.
The example below shows the commands to configure the IGMP query maximum response time.
Configure IGMP robustness value for layer3 VLAN 10
SMIS(config)#configure terminal

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SMIS(config)#interface vlan 10
SMIS(config-if)# ip igmp robustness 10
SMIS(config-if)# end
SMIS# s ow ip igmp interface
vlan10, line protocol is up
Internet address is 2.2.2.2/8
IGMP is enabled on the interface
Current IGMP router version is 2
IGMP query interval is 125 seconds
Last member query response interval is 10 seconds
IGMP max query response time is 100 seconds
Robustness value is 10
IGMP querying router is 2.2.2.2 (this system)
Fast leave is disabled on this interface
No multicast groups joined
1.8 Leaving a Multicast Group
Host computers leave multicast groups either silently or by sending IGMP leave messages. Switches
monitor the IGMP leave messages sent by host computers. When a switch receives an IGMP leave
message for any group on an interface, it does not immediately delete the interface from the group
entry on the multicast table. Instead, the switch sends an IGMP group-specific query message on the
interface that received the IGMP leave message. If there are any other IGMP hosts on that interface that
joined the same multicast group, the switch will receive an IGMP member report as a response. If no
hosts respond on that interface, the switch will assume that no other IGMP hosts are connected on that
interface for the same group and will delete the corresponding interface from the group entry on the
multicast table.
Switches follow the above process only for IGMP version 2 leave messages.
The following parameters are used to control the leave message handling procedure in Supermicro
switches.
Group Query Interval – This configures the amount of time a switch will wait to get response for its
group specific queries from IGMP hosts.
Immediate Leave – This configures the switch to have the host leave immediately instead of sending
group specific query messages to look for other IGMP hosts on the interface that received an IGMP
leave message.
These parameters can be configured as explained below.

IGMP Configuration Guide
Supermicro L2/L3 Switches
Configuration Guide
19
1.8.1 Last Member Query Interval
Switches send group specific query messages on the interface that received an IGMP leave message.
Switches wait for the group query interval time to get a response from the hosts for its group specific
query messages. If they receive any host member report as a response, they will drop the leave message
received earlier on that interface. If they do not receive any response from hosts for a group query
interval time, the switches will remove the interface from the group entry in the multicast forwarding
table.
Users can configure this last member query interval. The default last member query interval is 10
seconds.
Follow the steps below to configure the last member query interval.
Step Command Description
Step 1
configure terminal
Enters the configuration mode.
Step
2
interface
<
interface
-
type
>
<
interface
-
id
>
or
interface range <interface-type> <interface-id> ….
Enters the interface configuration
mode.
interface-type – may be any of the
following:
gigabit ethernet – gi
extreme-ethernet – ex
qx-ethernet – qx
vlan
interface-id is in slot/port format for all
physical interfaces. It may be the VL N
identifier for VL N interfaces.
To configure multiple interfaces, use
the “interface range …” command. To
provide a range use a hypen (-)
between the start and end interface
numbers. E.g.: int range gi 0/1-10
To provide multiple interfaces or
ranges, separate with a comma (,).
E.g.: int range gi 0/1-10, gi 0/20
If multiple interfaces are provided, the
next step will enable IGMP on all these
interfaces.
Note: While configuring IGMP on
physical interfaces (gi, ex, qx), make
sure those interfaces are configured as

IGMP Configuration Guide
Supermicro L2/L3 Switches
Configuration Guide
20
layer 3 interfaces using
the
“no
switchport” command in the interface
configuration mode.
Step 3
ip igmp
last
-
member
-
query
-
interval
<value>
Configures the
last member
query
interval.
The last member query interval value
can be any number from 1-255
seconds. Default is 2 seconds.
Step 4
end
Exits the configuration mode.
Step 5
s ow ip igmp interface
<interface-type>
<interface-id>
Displays the IGMP
last member
query
interval information for the given
interface(s).
Step 6
write startup
-
config
Optional step
–
saves this IGMP
configuration to be part of the startup
configuration.
The
“
no ip igmp
last
-
member
-
query
-
interval
”
command
resets the
last member
query
interval value to its default value of 10 seconds.
The last member query interval should be configured only on an IGMPv2 or IGMPv3
interface.
The example below shows the commands used to configure the last member query interval time.
Configure t e last member query interval time as 250 seconds for layer3 VLAN10.
SMIS(config)#configure terminal
SMIS(config)#interface vlan 10
SMIS(config-if)# ip igmp last-member-query-interval 250
SMIS(config-if)#end
SMIS# s ow ip igmp interface
vlan10, line protocol is up
Internet address is 2.2.2.2/8
IGMP is enabled on interface
Current IGMP router version is 2
IGMP query interval is 125 seconds
Last member query response interval is 250 seconds
IGMP max query response time is 100 seconds
Robustness value is 2
IGMP querying router is 2.2.2.2 (this system)
Fast leave is disabled on this interface
No multicast groups joined