Internet Group Management Protocol(IGMP) is used by hosts to for request multicast data for a particular multicast group. This communication takes place between the (igmp enabled)routers present in the subnet and the hosts. Hosts can subscribe to a multicast group or leave it using IGMP.
Questions tagged [igmp]
39 questions
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IGMP Router Mode VS Proxy Mode
I am trying to understand the difference between IGMP Router Mode and IGMP Proxy Mode here, http://technet.microsoft.com/en-us/library/cc957920.aspx
There is a question for an exam I am studying that asks
You are the network administrator for the…
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Glowie
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Is IGMP multicast traffic to a Xen VM host legitimate?
I run two Xen/CentOS 6.5 based VMs, both hosted by the same company, but connected to different networks (basic /24s w/ a single gateway at .1) in different physical locations. I developed an iptables firewall on the first host, part of which logged…
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synacksoldier
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IGMP 2.0 snooping switch timeout
Suppose a host computer has joined a multicast group 239.0.0.50 via IGMP 2.0. As per the IGMP 2.0 spec, when the host computer receives either a general query on 224.0.0.1 or a group wide query on 239.0.0.50, it is supposed to set a random delay…
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MK.
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How to allow IGMP traffic on Cisco switches?
I have a network formed by some Cisco switches (a 2960 at the center, some 2950s for distribution). The network uses VLANs, and there are trunks between the various switches. Computers in the same VLAN can happily talk across multiple switches.…
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Massimo
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In ubuntu, which process is sending igmp packets?
My Ubuntu keeps sending out IGMP Query requests for following IPs: 239.255.255.255.253, 224.1.1.7 and 234.55.66.77. I figured this out from Wireshark. As per IGMP spec, I believe query requests are sent only by routers. So,
Why is my machine…
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Manish
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Catalyst 3560G SPAN session not mirroring IGMP packets
I am developing a device which acts as a multicast host, and want to observe it as it responds to IGMP Queries.
My Catalyst 3560G is set up as follows (full config below): Port 0/1 is a TFTP server allowing the device under test to boot. Port 0/3…
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deemer
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Cisco multicast configuration
I'm on an isolated (for now) catalyst 3560e. I have a multicast source, which when enabled, causes flooding to all switch interfaces. I have a second different multicast source, which does not cause flooding, it only gets delivered to the sinks who…
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Dustin Getz
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Can a linux client in a multicast network get to know the source ip?
Supose I'm added as a client in a small multicast network with L2 switches and one unique router that is the LHR that uses IGMPv2. Can I (legally if possible) forward some signal that will give me the LHR or the source IP address?
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mranon
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cisco 4948 IGMP flooding on all ports
everyone
Having trouble with multicast on cisco WS-C4948-10GE (MPC8540).
I have two switches running:
System image file is "bootflash:cat4000-i5k91s-mz.122-25.EWA9.bin"
and
System image file is "bootflash:cat4500-entservicesk9-mz.122-46.SG.bin"
Both…
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Tomato
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running snort and IGMP v2 flooding
I am not a network guru so please bear with me. I am running snort on a PLC (running rt-linux) along with an application that needs to communicate with another instance of the same application residing on another PLC, via multicast. I have…
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awatan
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routing multicast trough debian miniPC eth0->eth1
Hello i have probably noob question by i already spent some time on it and messed a local network as well so:
I have miniPC for real time log purposes between network and IPTV set-top box. The box has DHCP on it so it can provide IP to the box as…
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J B
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Best practices for setting up multicast destinations
I am setting up a small LAN(20ish hosts) with a many devices which output multicast traffic. I am able to select their destination IP address and port number. There are 1-10 computers on the LAN which will subscribe to 0-to-all multicast streams.…
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fooOnYou
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Cisco Nexus 7000 Multicast IGMP Snooping enabled - packets got to all interfaces
I have connected three servers to Cisco Nexus 7000 switch.
Server1 send multicast packets, server2 subscribes to multicast packets and server3 is for the tests.
No matter if I subscribe to multicast from server2 or not all interfaces are flooded by…
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killdaclick
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Does the IP -> Ethernet multicast address mapping ambiguity matter for IGMP snooping switches?
There are 2^28 possible IP multicast addresses, but only 2^23 possible Ethernet (MAC) multicast addresses (http://technet.microsoft.com/en-us/library/cc957928.aspx), which is why e.g.
224.1.1.1 gets mapped to the same MAC address as…
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Evgeniy Berezovsky
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Possible to emulate an IGMP querier in software?
I have a L3 switch that does IGMP snooping, but it cannot act as an IGMP querier, and there is no IGMP querier connected to this network.
Would it be possible to implement an IGMP querier in software, so that my L3 switch can snoop on it and route…
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Evgeniy Berezovsky
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