Igmp snooping querier. Command Objective. Switches are named TOR1, TOR2, TOR3, TOR4, CORE. Authority Figure 1: Example IGMP Snooping Topology. Lastly, if your switches do not have Jul 2, 2016 · I know igmp is in layer 2 and pim if there is layer 3. 查询器周期性的发送普遍组查询报文，维护VLAN内的组成员关系 Nov 1, 2023 · Remember to set them as 'passive'. And all vlans SVIs is created on N5k. When enabled, the IGMP snooping querier uses the IP address as the query source address. Select Switching > Multicast > IGMP Snooping Querier VLAN Configuration. Apr 14, 2022 · The switches elect a querier based on its IP address, and the lowest IP address is elected as the querier. 1 255. The Internet Group Management Protocol (IGMP) is a protocol that allows several devices to share one IP address so they can all receive the same data. The MLD snooping querier disables itself if the IPv6 address is cleared. igmp-version (2 | 3): Selecciona la versión de IGMP para las consultas de membresía. It’s also more efficient than broadcast because only receivers that are actually interested in our traffic will receive Procedure. Use this page to configure the global IGMP (Internet Group Management Protocol) snooping querier settings on the device. To configurethe IGMP snooping querier, perform this procedure. Enter system view. It’s more efficient than unicast since we only have to send our traffic once, this saves us precious bandwidth. 17. If the switch is enabled as a IGMP Querier, it starts after 60 seconds have passed. set ip 172. The querier is there simply to make IGMP queries within the vlan so that all switches running IGMP snooping can listen to the IGMP responses and update their mac address tables accordingly. 255. In the presence of. The value range is between 60 to 600 seconds. For good network performance, ensure that there is only one IGMP querier in the network. This command sets the time interval at which the IGMP snooping queries are sent by the Switch when configured as querier on a VLAN. Cisco has a document which describes the problem (and Cisco-specific solutions). Understanding IGMP Snooping. • The IGMP snooping querier sends IGMPv3 querier messages. ip igmp snooping querier query-interval interval-count (Optional) Set the interval between IGMP queriers. cer no mac authentication Feb 7, 2024 · Para habilitar IGMP y MLD Snooping en MikroTik RouterOS, se utilizan las siguientes opciones de configuración: igmp-snooping (yes | no): Habilita o deshabilita IGMP y MLD Snooping en el bridge. 2, igmp is enabled. Dec 2, 2020 · When an IGMP snooping querier is enabled, it sends out periodic IGMP queries that trigger IGMP report messages from hosts that want to receive IP multicast traffic. TOR4 has a multicast source in it broadcasting on UDP 239. The election of the Querier is done based on the lowest IP-address. Enter VLAN view. In order to restrict multicast being broadcasted to all ports in the first VLAN, IGMP Snooping Querier is enabled on the switch and this is working fine ion this VLAN. The range is 1 to 18000 seconds. No reports then nothing for snooping to snoop and it eventually filters everything. IGMP. All the servers need to talk to a single multicast address and I am having trouble getting them to communicate. 1 We would like to show you a description here but the site won’t allow us. If a VLAN has a connection to a PIM-enabled port on another router, the VLAN must be configured as a non-querier. After receiving an IGMP general query, the Layer 2 device forwards the query to all ports in the VLAN or VSI except the receiving port. IGMP snooping requires that one central switch or router periodically query all end-devices on the network to announce their multicast memberships. 3. For example, if IGMP snooping is enabled and the querier's version is IGMPv2, and the switch receives an IGMPv3 report from a host, then the switch can forward the IGMPv3 report to the multicast router. The IGMP snooping querier does not generate an IGMP general query if it cannot find an available IP address on the device. The two primary hardware resources to consider when selecting the IGMP snooping hardware filters are the May 11, 2008 · IGMP Snooping Querier. A screen similar to the following displays. enabled, the IGMP snooping querier uses the IP address as the query source address. The default factory configuration on legacy EX Series switches enables IGMP snooping by default on all VLANs. Mar 2, 2019 · The below is with the GUI if you need CLI commands just let me know. other IGMP Queriers, the switch might (or might not) stop sending queries, based. When enabled, the IGMP snooping querier restarts if you configure an IP address. Since it has not heard any query yet, it starts to send the query and once the first L3 device receives it, since the query that it received has an lower ip, it lets the 2nd device be We would like to show you a description here but the site won’t allow us. # Create VLAN 100, and assign GigabitEthernet 1/0/1 through GigabitEthernet 1/0/3 to the VLAN. The value of Response Time of IGMP-snooping is set to ten seconds. 0. If a multicast router supporting IGMP is not present, then the switch must assume this function in order to elicit Apr 12, 2024 · Configuring an IGMP Querier. Specifically, IGMP allows devices to join a multicasting group. 2(01) 78-20604-03 7 IGMP Snooping Command Reference show ip igmp Jun 28, 2017 · The IGMP snooping querier does not generate an IGMP general query if it cannot find an available IP address on the device. By default, IGMP snooping is disabled for a VLAN. 4. configure a SVI interface belongs to the vlan with "ip pim sparse-dense-mode" on one switch. In the Querier IP Address field, enter 10. I prefer the SVI because here I can see more information’s with the sh ip igmp command. IGMPv2 supports IGMPv1, and IGMPv3 supports IGMPv2. May 20, 2020 · All these switches route to a CORE switch. Mar 25, 2018 · For your diagram, if IGMP snooping is enabled on both switches and there's a querier (your router), yes hosts on either switch should obtain the multicast stream. multicast-querier (yes | no): Habilita al bridge para generar An IGMP querier sends queries; a non-querier listens for IGMP queries and forwards them to the entire VLAN. Oct 13, 2011 · The Sx300 is not a full. Enter Name, Interface IP, and VLAN. When there is no multicast router in the VLAN to originate the queries, you must configure an IGMP snooping querier to send membership queries. # Enable the IGMP snooping querier function in VLAN 100. 5. Observe these guidelines when configuring the IGMP snooping querier: Configure the VLAN in global configuration mode. 使能了VLAN内IGMP Snooping之后，该功能只会在已加入该VLAN的接口上生效。. igmp-snooping querier-vlan vlan-list 6. message. Next, it is necessary to enable certain IGMP options on the VLAN itself to ensure everything runs smoothly. So if I have nexus 5k as core and 2960 edges. SW2 will flood the query in the received vlan. VLANs can be independently configured to be queriers or non-queriers. IGMP snooping : Enabled IGMPv2 immediate leave : Enabled Explicit host tracking : Enabled Multicast router learning mode : pim-dvmrp CGMP interoperability mode : IGMP_ONLY Last member query interval : 1000 Topology change : No #show ip igmp snooping querier vlan 68 detail IP address : 10. 如果用户加入的组播组地址为ASM型，需要使用 igmp snooping ssm . With IGMP snooping enabled, the device monitors IGMP traffic on the network and uses what it learns to forward multicast traffic to only the downstream interfaces that are connected to interested receivers. # Enable IGMP snooping and the function of dropping unknown multicast traffic in VLAN 100. Currently, you can configure the same SVI IP address for the switch querier and the IGMP snooping querier. If a multicast router supporting IGMP is not present, then the switch must assume this function in order to elicit Jul 11, 2023 · To define the source IP address that the IGMP snooping querier uses, use the ip igmp snooping vlan querier address command in Global Configuration mode. 使用 igmp snooping ssm-mapping enable 命令用来使能VLAN内的SSM Mapping功能。. Some switches magically and silently disable igmp snooping in the absence of a querier. Aging time is the maximum number of seconds that the system will retain a multicast snooping entry. It immediately becomes querier and starts to send query packet. Igmp snooping requires a querier somewhere on the network to function. Config# no ip igmp snooping. When you have an IGMP Snooping Querier (like a gateway that is configured to support it) then the IGMP May 30, 2021 · Say on device with ip 10. Where to configure igmp snooping querier ir configuring PIM on all N5k interface vlans make no need for igmp snooping querier ? Thanks Aug 30, 2013 · Following configurations help to solve: configure "ip igmp snooping querier address x. 1 as the source IP address of IGMP general queries. That said, without an mrouter in the network, you need to configure one (or more) igmp querier s. igmp-snooping query-max-respond time Oct 22, 2007 · Note The IGMP snooping querier does not generate an IGMP general query if it cannot find an IP address on the switch. [SwitchA-vlan100] igmp-snooping querier [SwitchA-vlan100] quit # In VLAN 100, specify 192. Again if IGMP snooping is enabled but now the querier is not present (your router), hosts on either switch should not obtain the multicast stream. In this way, the device builds an IGMP snooping table that has a list of all the enabled, the IGMP snooping querier uses the IP address as the query source address. The IGMP snooping querier supports IGMP Versions 1 and 2. The DR is the device with the highest IP address on the subnet, whereas the IGMP querier is the device with the lowest IP address. igmp-snooping query-interval interval 7. igmp-snooping querier version version-id 5. g. Jan 2, 2003 · The following items provide recommendations for configuration of a network switch for IGMP snooping: Set the IGMP query interval to 60 seconds or 125 seconds. In a multicast network that runs IGMP, you do not need to configure an IGMP snooping querier because it may affect IGMP querier elections by sending IGMP general queries with a low source IP address. This is what the switch should do with IGMP snooping disabled. And What is the impact If I disable IGMP Snooping Querier globally and enable on specfic SVI? Config# no ip igmp snooping querier. If the multicast router does not exist in VLAN where IGMP-snooping is activated, the . How IGMP snooping works. IGMP Snooping is a feature for switches to learn what multicast groups are needed on which ports. Configures an IGMP querier on an interface, depending on the command context you are in. Jul 13, 2010 · By default IGMP snooping is Enabled and IGMP snooping querier is disabled : D7402_DC(config)#ip igmp snooping vlan 4 querier. If IGMP snooping is not enabled on vlan100, the switch floods the multicast traffic on all Configuring the IGMP-snooping querier; Configuring global IGMP-snooping settings. 1, version: 3 Querier interval: 125 secs Querier last member query interval: 1 secs Querier robustness: 2 Switch-querier enabled, address 192 Mar 17, 2016 · The DR and the IGMP querier are selected based on different criteria and may be different devices on the same subnet. ip igmp snooping querier tcn query [count count | interval interval] The software allows you to choose between two types of IGMP snooping hardware filters: per-port filters (the default) and per-VLAN filters. # Enable the IGMP snooping feature. capability IGMP Querier. Multicast routers available within this VLAN. When multiple IGMP snooping devices are connected To enable IGMP snooping for a VLAN in IGMP-snooping view: 1. Command context. IGMP snooping enables the device to selectively send out multicast packets on only the ports that need them. Wenn es aktiviert ist, wird der Bandbreitenverbrauch in einer Multi-Access-LAN-Umgebung reduziert, um eine Überflutung des gesamten VLANs zu vermeiden, und gleichzeitig kann auch die Netzwerkinformationssicherheit verbessert werden. So of course I enable it globally; and IGMP snooping querier is applied on all VLANs. IGMP is a network layer protocol used to set up multicasting on networks that use the Internet Protocol version 4 (IPv4). Feb 19, 2013 · Just to clarify, What is the impact If I disable IGMP Snooping disabled globally and enable on specific SVI? e. Select or Add an interface. 在配置参数时，要确保“IGMP查询报文最大响应时间”<“IGMP普遍组查询报文发送间隔”。. Nov 21, 2017 · You can configure an IGMP snooping querier to support IGMP snooping in subnets without multicast interfaces because the multicast traffic does not need to be routed. Feb 16, 2011 · 1) One VLAN with multicast, no queriers within the VLAN. Dec 1, 2022 · Routers also use IGMP to advertise multicast group memberships to neighboring switches and routers. Then igmp is enabled on second device 10. • When administratively enabled, the IGMP snooping querier moves to the nonquerier state if it detects the presence of a multicast router in the network. Switch A (which is close to the multicast sources) acts as the IGMP snooping querier. Sep 23, 2014 · When an IGMP snooping querier is enabled, it sends out periodic IGMP queries that trigger IGMP report messages from hosts that want to receive IP multicast traffic. To function, Layer 3 aware devices listen to join and leave messages from clients wanting to join and leave multicast groups through use of an IGMP Querier, common setups rely on a Designated Querier (DQ) per VLAN. Set IGMP snooping to v2 or v3. These versions are interoperable on the switch. 2 IGMP version : v2 Port : Switch Max response time Apr 25, 2012 · The IGMP snooping querier disables itself if the IP address is cleared. 1. IGMP snooping is enabled globally. igmp-snooping querier 4. When enabled, the MLD snooping querier restarts if you configure an IPv6 Use the show ip igmp snooping querier command to display the IGMP version and the IP address of a detected device, also called a querier, that sends IGMP query messages. SUMMARYSTEPS 1. When there are multiple receivers on the network then using multicast traffic is a good idea. x and Cisco IOS Release 15. The no form of this command disables IGMP querier on an interface. Use the following commands to configure the global IGMP-snooping settings. Routers not handling multicast routing don't care. (Optional) Check the IGMP Querier Election check box to elect this device as the querier. 1. It has been my experience that without an IGMP Snooping Querier on the network, multicast traffic effectively flows like a network broadcast within a VLAN (broadcast domain) and will hit every attached node. Feb 16, 2024 · The process to enable IGMP snooping can vary based on the device and its operating device/software. This is not a vendor When an IGMP snooping querier is enabled, it sends out periodic IGMP queries that trigger IGMP report messages from hosts that want to receive IP multicast traffic. When a multicast-enabled router first becomes active on a subnet, it assumes that it is the Querier — the router responsible for sending all General and Group-Specific Queries to the subnet - and immediately sends a General Query. Query. 3 - IGMP Querier Election. query. In this case, you don’t need any other configuration for IGMP snooping to work. Some of the switches I have seen are smart enough to wait and see if there is another querier before turning their's on. A subnet can have multiple multicast routers but has only one IGMP querier. When administratively enabled, the IGMP snooping querier moves to the nonquerier state if it detects the presence of a multicast router in the network. • If there is no IPv6 address configured on the VLAN interface, the MLD snooping querier does not start. querier. Config-if)#ip igmp snooping. x". 2. IGMP querier is available as of firmware version MS 9. 1) to SW2; Because the SW2 receives the IGMP query, it will install the uplink to sw1 as mrouter port, in the snooping table. Without IGMP snooping, the device floods the packets on every port. The default value is 300. IGMP Snooping Querier When there is no multicast router in the VLAN to originate the queries, you must configure an IGMP snooping querier to send membership queries. and query cycles for general queries. In the VLAN ID field, enter 1. 全局使能IGMP Snooping后，建议在其他全部的VLAN内都使能IGMP Snooping，这样可以避免VLAN内的IGMP Flags: I -- IGMP snooping, S -- Static, P -- PIM snooping, A -- ASM mode Vlan Group/source Type Version Port List-----2 224. The device listens for the exchange of IGMP messages by the device and the end hosts. Jul 29, 2011 · IGMP snooping is supported on all Ethernet interfaces. "ip igmp snooping querier". with no IGMP traffic (queries) detected from a Multicast router. Internet Group Management Protocol (IGMP) snooping constrains the flooding of IPv4 multicast traffic on VLANs on a device. 10. I noticed on the VLAN I am interested in (or the VLAN I would expect traffic on, the normal lab VLAN) all switches know the querier is 10. Since that is the part most people forget about (or don't realize), switch manufacturers started including queriers so their snooping would always work. Sep 24, 2012 · I am having a Multicast issue with a cluster of Linux servers that need to talk Multicast for cluster/high-availability operation. As an example, if the IP address used for IGMP snooping querier is also used for another router on the segment, then there will be issues with the IGMP querier election protocol. Although the IGMP version of the querier messages is not configurable, the querier is compatible with IGMPv2 hosts. Config# inter vlan 1. and source is connected to N5k in vlan 100. or. Step 5. 100 from one of the hosts—for example, Host B. 1X53 and 15. IGMP snooping listens to these IGMP reports to establish appropriate forwarding. 168. The Layer 2 device also performs one of the following IGMP Snooping配置在二层组播设备上，通过对上游三层设备和下游用户之间的IGMP报文进行分析，建立和维护二层组播转发表，实现组播数据报文在数据链路层的按需分发。 IGMP Snooping (Internet Group Management Protocol Snooping)是一种IPv4二层组播协议，通过侦听三层组播设备和用户主机之间发送的组播协议报文来 The IGMP snooping querier does not generate an IGMP general query if it cannot find an available IP address on the switch. Enable IGMP snooping querier. This functionality will allow an interface to join in the querier-election process. 5. [SwitchA-vlan100] igmp-snooping general-query source-ip 192. Fortinet Documentation Library Configuring IGMP Snooping Querier. You can configure an IGMP snooping querier to support IGMP snooping in subnets without multicast interfaces because the multicast traffic does not need to be routed. Both queriers will then be active at the same time, and both queriers will send general queries to the VLAN periodically. Enter an integer value from 15 to 3600. SW1 sends the IGMP general membership queries (224. ip igmp querier no ip igmp querier Description. When a switch is connected to a network and IGMP querier is enabled, it will assume it is the querier until it hears a General Query from another router or switch with a lower IP address. Enable IGMP snooping globally and enter IGMP-snooping view. If a port spanning-tree, a port group, or a VLAN ID change occurs, the IGMP snooping-learned multicast groups from this port on the VLAN are deleted. When a host wants to receive multicast traffic, its implementation of IGMP sends an IGMP Membership report 在同一VLAN内，IGMP Snooping查询器功能和IGMP Snooping Proxy功能不能同时配置。. config system interface. † If there is no IP address configured on the VLAN interface, the IGMP snooping querier does not start. 2) A second VLAN, received via a trunk restricting only this VLAN. IGMP message types include: Query, Report (Join), and Leave Group. To configure an IGMP querier: Navigate to Switch > Configure > Routing and DHCP. After this, Run VLAN ID and enable multicast forwarding mode, by default, it will [SwitchA-vlan100] igmp-snooping enable [SwitchA-vlan100] igmp-snooping drop-unknown # Configure Switch A as the IGMP snooping querier. Config# inter vlan 1 Also network switches will need to have both IGMP Snooping and Querier functionality. （可选）配置查询器选举功能。. The IGMP snooping querier disables itself if the IP address is cleared. IGMP-Snooping ist ein wichtiges Merkmal von Netzwerk-Switches. By default, IGMP snooping is globally disabled. Dec 13, 2018 · The objective of this document is to show you how to configure IGMP Snooping on the 200/300 Series Managed Switches. When enabled, the MLD snooping querier uses the IPv6 address as the query source address. Configure an IP address on the VLAN interface. Mar 1, 2016 · There is a problem with IGMP snooping across switches since the IGMP message on one switch doesn't get send to the other switch, so the switch with the source will not know that the port to the other switch should receive the multicast frames. Step 13. ip igmp snooping query-interval. Configuration procedure. There can only be one IGMP Querier in a network. function of IGMP-snooping can be used to imitate the multicast router to regularly send IGMP . 7 Configuring Querier of IGMP-Snooping . 使用 igmp snooping version 命令配置VLAN内IGMP Snooping的版本号为3。. The general steps for enabling IGMP snooping on common devices are as follows: Run System view, run IGMP snooping enable option. IGMP Snooping. x. Command did not take effect due to reason: IGMP switch querier is globally disabled. (Optional) Choose the IGMP Querier Version used if the device becomes the elected An IGMP Snooping Querier is a network function involved in the management of multicast traffic when using IGMP in conjunction with IGMP snooping on a switch. config t ip igmp snooping vlan configuration 2 ip igmp snooping ip igmp snooping explicit-tracking ip igmp snooping fast-leave ip igmp snooping last-member-query-interval 3 ip igmp snooping querier 172. 68. Internet Group Management Protocol (IGMP) is an IPv4 protocol that a multicast receiver uses to communicate with an interface on a Palo Alto Networks® firewall and that the firewall uses to track the membership of multicast groups. Cisco NX-OS supports IGMPv2 and IGMPv3. The term snooping is used because Layer 3 control plane packets are intercepted and influence Layer 2 forwarding decisions. # Set the source IP address of IGMP general IGMP and IGMP Snooping/Querier. 1 I v2 Te7/4 Te5/2 Gi41/1 Gi41/44 Gi51/1 Gi51/44 Te4/2 Cisco CPT Command Reference Guide–CTC and Documentation Release 9. 52. The switch supports IGMP version 1, IGMP version 2, and IGMP version 3. " The IGMP querier is what coordinates the location on the network of the multicast sources. In this example topology, the multicast router forwards multicast traffic to the switch from the source when it receives a membership report for group 233. 1 interface May 5, 2020 · SW2 is configured with IGMP snooping. 106 ip igmp snooping report-suppression ip igmp snooping mrouter interface ethernet 2/1 ip igmp snooping static-group 230. Enable the IGMP snooping querier on VLAN 1. Here is the key part, the endpoint device has to send a join every minute or so, or the switch cuts off the stream. The recommended setting is the default setting of the network switch. Click Add. I believe I need to enable IP IGMP Snooping Querier on the N7K's and it needs to be enabled on the VLAN Mar 29, 2015 · With IGMP snooping enabled and no querier (no querier, no PIM) the switch should drop all multicast packets because of igmp snooping and no known groups. All receiver hosts run IGMPv2, and all switches run IGMPv2 snooping. The IGMP snooping querier performs querier election as described in RFC 2236. If there are multiple switches configured to function as a querier, a querier election takes place. If there is no IP address configured on the VLAN interface, the IGMP snooping querier tries Mar 29, 2023 · For Querier Admin Mode, select the Enable radio button. • The IGMP snooping querier supports IGMP Versions 1 and 2. To make multicast work correctly, you need to have IGMP snooping enabled on all the VLANs on all the switches to which your devices are May 5, 2017 · ip igmp snooping querier!! crypto pki trustpoint TP-self-signed-1768263040 enrollment selfsigned subject-name cn=IOS-Self-Signed-Certificate-1768263040 revocation-check none rsakeypair TP-self-signed-1768263040!! crypto pki certificate chain TP-self-signed-1768263040 certificate self-signed 01 nvram:IOS-Self-Sig#1. This central device is the IGMP querier. IGMP snooping is now available on all platforms and conforms to RFC4604 standards. # Configure Switch A as the IGMP snooping querier. 1 Querier election process 使用 igmp snooping enable（VLAN或BD视图） 命令使能VLAN的IGMP Snooping功能。. Log into the M4300 GUI, and click blue button APPLY before leaving each page below: - Go to Switching\Multicast\IGMP Snooping\Configuration: have all three IGMP Snooping Configuration Admin Mode, Validate IGMP Header and Proxy Querier mode ENABLE. configure terminal 3. edit "vlan_10". Jul 2, 2022 · You shouldn't need to configure the querier on every switch, you just need it on one of the switches. 2 (for VLAN 110) except TOR4. Step 14. A message sent from the querier (multicast router or switch) asking for a response from each host belonging to the multicast group. As far as I understand it there’s two parts to IGMP snooping 1) the snooping which does the filtering and 2) the querier/mrouter which send out igmp reports that all the multicast listeners respond to which keeps the switch from filtering the stream to that port. set switch -controller-igmp-snooping-proxy enable. Query messages are used to elect the IGMP querier as follows: 执行命令 igmp-snooping enable ，使能流量模板下的IGMP Snooping功能。 使能流量模板下的IGMP Snooping功能后，AP通过侦听用户上报的组播报告报文和离开报文来维护二层组播转发表项，实现组播数据向用户侧的精确转发。 To enable IGMP snooping querier: 1. Jul 25, 2018 · fab4-p1-leaf1# show ip igmp snooping vlan 19 IGMP Snooping information for vlan 19 IGMP snooping enabled Lookup mode: IP Optimised Multicast Flood (OMF) disabled IGMP querier present, address: 192. More specific forms of snooping, such as Internet Dec 13, 2018 · A querier sends query messages to discover which network devices are members of a given multicast group. enable 2. set switch -controller-igmp-snooping enable. It should not flood them. If a port spanning tree, a port group, or a VLAN ID change occurs, the IGMP snooping-learned multicast groups from this port on the VLAN are deleted. Snooping is a general way for Layer 2 devices, such as Juniper Networks MX Series Ethernet Services Routers, to implement a series of procedures to “snoop” at the Layer 3 packet content to determine which actions are to be taken to process or forward a frame. Step 4. 20. The two types of IGMP snooping hardware filters use switch hardware resources in different ways. At that point, it becomes a "non-querier. An IGMP snooping enabled Layer 2 device performs differently depending on the message type. When an IGMP snooping querier is enabled, it sends out periodic IGMP queries that trigger IGMP report messages from hosts that want to receive IP multicast traffic. 执行本命令前，需在系统视图下执行 igmp-snooping enable（系统视图） 命令使能全局IGMP Snooping功能。. 16. Sep 22, 2017 · The SVI IP address must not be used as the querier IP address or it will result in issues with querier election. To return to the default, use the no form of this command. # Enable IGMP snooping globally. The no form of the command sets the IGMP querier interval to default value. Starting in Junos OS Releases 14. Enable IGMP snooping for specified VLANs. 2, QFabric Systems support the igmp-querier statement to configure a Node device as an IGMP querier. # Enable IGMP snooping, and enable dropping unknown multicast data for VLAN 100. The IGMP querier periodically sends IGMP general queries to all hosts and routers on the local subnet to check for the existence of multicast group members. When it comes to IGMP, a network switch can have 2 roles: Querier or non-Querier. config-if-vlan. Click Apply. It is therefore very important that all IGMP switches have a different IP-address. ls wi ib yh uf bg jo wk zy ga