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Example for Configuring Basic IGMP Snooping

Example for Configuring Basic IGMP Snooping

Owned by Tracy Yang (Unlicensed)
Last updated: Sep 27, 2022

Networking Requirments

Figure 1. IGMP Snooping Networking

As shown in Figure 1, Host A, Host B, and Host C connect to a multicast source through a Layer 2 Switch and a Layer 3 Router to receive multicast data from the Source device.

Perform the following procedures on the Switch to implement IGMP snooping:

  •   Create a VLAN and add interfaces Ge-1/1/1, Ge-1/1/2 and Ge-1/1/3 to the VLAN.
  •   Enable global and VLAN-based IGMP snooping function.
  •   Host C wants to receive multicast data from multicast group 238.255.0.1 stably for a long time, so configure the connecting interface Ge-1/1/1 as a static member port.
  •   To prevent aging of dynamic routing interfaces, configure Ge-1/1/3 as a static router port.

Procedure

Step1         Configure VLAN.

admin@XorPlus# set vlans vlan-id 2
admin@XorPlus# set interface gigabit-ethernet ge-1/1/1 family ethernet-switching native-vlan-id 2
admin@XorPlus# set interface gigabit-ethernet ge-1/1/2 family ethernet-switching native-vlan-id 2
admin@XorPlus# set interface gigabit-ethernet ge-1/1/3 family ethernet-switching native-vlan-id 2

Step2         Enable the global IGMP snooping function.

admin@Xorplus# set protocols igmp-snooping enable true

Step3         Enable the VLAN-based IGMP snooping function.

admin@Xorplus# set protocols igmp-snooping vlan-id 2 enable true

NOTE:

After the global IGMP snooping is enabled, IGMP snooping in the VLAN is disabled by default. To enable IGMP snooping in a VLAN, you also need to enable the VLAN-based IGMP snooping function.

After IGMP Snooping is enabled in a VLAN, it will take effect only on interfaces that have already been added to this VLAN.

Step4          (Optional) Configure the number of times that the querier sends a group-specific query message.

admin@Xorplus# set protocols igmp-snooping last-member-query-count 2

Step5         (Optional) Configure the interval that the querier sends a group-specific query message.

admin@Xorplus# set protocols igmp-snooping last-member-query-interval 2

Step6         (Optional) Configure the maximum response time for IGMP general queries.

admin@Xorplus# set protocols igmp-snooping max-response-time 10

Step7         (Optional) Configure the interval of sending an IGMP general queries.

admin@Xorplus# set protocols igmp-snooping query-interval 60

Step8         (Optional) Enable the membership report suppression function.

admin@Xorplus# set protocols igmp-snooping report-suppression true

Step9         (Optional) Configure the IGMP robustness coefficient.

admin@Xorplus# set protocols igmp-snooping robustness-variable 2

Step10         (Optional) Configure aging time of dynamic router port.

admin@Xorplus# set protocols igmp-snooping router-aging-time 260

Step11      (Optional) Enable the fast leave function to allow member ports in a VLAN to quickly leave the multicast group.

admin@Xorplus# set protocols igmp-snooping vlan-id 2 fast-leave true

Step12      (Optional) Configure the querier in the VLAN.

admin@Xorplus# set protocols igmp-snooping vlan-id 2 querier enable true
admin@Xorplus# set protocols igmp-snooping vlan-id 2 querier address 192.168.12.100
admin@Xorplus# set protocols igmp-snooping vlan-id 2 querier version 2
admin@Xorplus# set protocols igmp-snooping vlan-id 2 querier other-querier-timer 120

Step13      Configure the interface as a static router port in the specified VLAN.

admin@Xorplus# set protocols igmp-snooping vlan-id 2 mrouter interface ge-1/1/3

Step14      Configure a static member interface to the multicast group.

admin@Xorplus# set protocols igmp-snooping vlan-id 2 static group 238.255.0.1 interface ge-1/1/1

Verify the Configuration

  •   You can use the run show igmp-snooping command to view the configuration information of IGMP snooping.   
admin@XorPlus# run show igmp-snooping
Global IGMP Snooping configuration:
-------------------------------------------
IGMP snooping             : Enabled
Report suppression           : Enabled
Robustness variable          : 2
Router aging time            : 260
Max response time            : 10
Query interval               : 60
Last member query count      : 2
Last member query interval    : 2


admin@XorPlus# run show igmp-snooping vlan 2
Vlan 2:
----------------------------------------------
IGMP snooping                    : Enabled
IGMPv2 fast leave                  : Enabled
IGMP querier state                  : Enabled
IGMP querier source ip address        : 192.168.12.100
IGMP other querier timer             : 120
IGMP querier version                : 2  


  • You can use the run show igmp-snooping groups command to show information about multicast group member ports which is used for Layer 2 forwarding, namely, the Layer 2 forwarding table.    
admin@XorPlus# run show igmp-snooping groups 
Vlan      Group                Port List          Type 
--------  ------------------      -----------------   ----------------------
 2      238.255.0.1              ge-1/1/1           Static                                             
                                   ge-1/1/3           Mrouter 
  •   You can use the runshow igmp-snooping querier command to show the configuration information and status of the querier.     
admin@XorPlus# run show igmp-snooping querier vlan 2
Vlan 2:   IGMP switch querier status
--------------------------------------------------------
admin state                    : Enabled
admin version                  : 2
source IP address              : 192.168.12.100
other querier timer            : 120
operational state              : Active
  •   You can use the run show igmp-snooping mrouter command to show the information about IGMP snooping router port.      
admin@XorPlus# run show igmp-snooping mrouter
Vlan      Ports            Type
--------    -------------     ---------
1         ge-1/1/3         Static

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