In computer networking, multicast is the delivery of a message or information to a group of destination computers simultaneously in a single transmission from the source. Copies are automatically created in other network elements, such as routers, but only when the topology of the network requires ...

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One of two machines on same network doesn't receive multicast group memberships

in remote network, we have two machines. one of them receives multicast subscriptions, another one doesn't machine one receives only igmp query: sudo tcpdump -nevv -i eth1 -s 1515 igmp tcpdump: ...
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30 views

Hyper-V Windows hosts see/count multicast traffic that they shouldn't

I have some of my Hyper-V VM's on a network segment that pushes a lot of UDP multicast traffic (several 100MBit/s). Now, all Hyper-V Windows hosts actually see and count the traffic on the Ethernet ...
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67 views

Unicast to multicast IPTV playlist via router bash

I've a TP-LINK TD-W8968 v3 with Busybox access. These are the command: help : ? help logout exit quit reboot adsl xdslctl xtm brctl cat loglevel logdest ...
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18 views

Cant get multicast to work across VLANs using pfsense router

I have a pfsense router as a VM on hyper-v, on which I have configured multiple VLANs. I have an application on VLAN1 (10.60.1.0/26) which multicasts to multiple VMs on another VLAN2(10.70.1.0/26). ...
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12 views

Is there a way to tell a machine accesible via a gre tunnel to join multicast groups via pimd or smcroute?

this has been stumping me for some time and would love any help on this. So I am subscribed to a data vendor through an intermediary firm. The intermediary firm has physical connections to the data ...
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61 views

Joining a UDP multicast through a server on the other side of the tunnel

I've drawn a diagram below to help with this question! So a company published a multicast UDP feed (company A) and another company connects to it (Company B). I have a point-to-point tunnel to ...
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36 views

how to find the number of members in a Windows IP multicast

I am able to find multicast groups by using this in Command Prompt (I found this at serverfault How do I know if IP Multicasting is enabled on my network in Windows?). netsh interface ip show joins ...
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68 views

Multicasting (mDNS) for Linux Server

Background: I am running a Linux sever on a local network that acts as both a web server and a central communications server. This server communicates with multiple nodes in the system. Upon node ...
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53 views

IP Multicast between Windows and Linux

Our team is developing linux/windows applications for our network that are talking to each other via multicast. We had it working when we only had linux boxes on the network, but we recently added a ...
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84 views

How can I forward UDP Multicast between two interfaces on Linux?

I have 3 Hosts (A,B,C), all with two network interfaces with, lets say, following ips: - A: - eth0 :192.168.0.2 - eth1: 10.0.1.1 - B: - eth0: 192.168.0.3 - eth1: 10.0.2.1 - C: - eth0: ...
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88 views

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 ...
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22 views

How to add multicast IP address to multicast group on linux

How to add multicast IP address to multicast group on linux? I am trying to edit /proc/net/igmp file, but it is read only, or there is other way. Thanks beforehand.
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26 views

Two identical networks, sending multicast data(how to connect?)

let me explain the problem, we have two identical networks, by identical I mean same devices with same IP addresses on both networks, these two network will send multicast data, now I want to connect ...
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293 views

OpenVPN - OpenVZ - Multicast and how to enable it

Good day all My application makes primary use of Multicast packets on ip = 224.8.0.1 I have tested over normal Wifi/Ethernet and hosted networks, which are all good. Problem: My OpenVZ ...
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32 views

What command should I use in Ubuntu to make it join a multicast group?

I have an ubuntu machine and would like it to join a multicast group. I came across iperf and I can launch a multicast server via iperf command (by using -B option). I can see the router has the IGMP ...
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68 views

how to forward multicast to multicast via iptables

I want to forward incoming multicast traffic to other multicast address listened on my server interface. My machine running on Ubuntu 14.04. Have a incoming traffic on 239.0.0.1 udp port 1001, want to ...
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43 views

When a host joins a multicast group, does it needs to change its ip address to the multicast group's ip address?

I'm talking about IPv4. If not, does the host use 2 IP addresses, one for multicast communication and one for "regular" communication?
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60 views

Sending multicast over VPN (with buffering)

I am trying to connect two sites using VPN (OpenVPN) to transmit multicasts (IPTV) from one site to another. I have created a layer2 VPN and it works, however, multicasts are very sensitive to packet ...
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43 views

Cisco 2960-X switch converting unicast video stream to multicast video stream

Can we convert unicast video stream to multicast video stream just using Cisco 2960-X switch ? Note: I tried to route incoming stream to 235.6.6.6 as it is my multicast ip adress, I used. In order ...
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1answer
55 views

10GB Ethernet latency, unsaturated cross-connect

I'm using shared (between few clients of a vendor) 10GB cross-connect in exchange data center. We receive few multicast data streams (each stream delivers data on some group of "stocks"/derivatives). ...
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28 views

How many available IPv6 multicast prefixes are there?

How many freely available multicast prefixes are there? The RFC specifies every ff00::/8 as the required prefix. Accordingly, there are 16*16 = 256 multicast prefixes. However, a large part are ...
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1answer
505 views

Machine with bonded interface does not receive multicast packets on all slave interfaces

After an upgrade of our machines from RHEL 6.6 to RHEL 6.7 we observed a problem where 4 of our 30 machines only receive multicast traffic on one of their two slave interfaces. It is unclear if the ...
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258 views

individual windows machine refuses to join multicast group on any network interface

I have written a piece of software which joins a multicast group and processes packets. This seems to work on a number of machines I've tested with, both with Windows (tested on XP through to 8.1) and ...
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174 views

In Infiniband networks, what is an MGID and how does it relate to multicast group?

I have this error in my Open Subnet manager log. Sep 22 01:49:53 router3-1 docker[12431]: Sep 22 01:49:53 089580 [68860700] 0x01 -> mcmr_rcv_join_mgrp: ERR 1B11: Port 0x10c37b1f7ebb0001 (MT25408 ...
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13 views

How do I work out the netmask for a multicast address [duplicate]

I have a simple test setup: local network 2 Linux PCs: one sender, one receiver on the sending pc and one receiver on another pc. If I send out on 224.0.0.1, the receivers get the payload. If I send ...
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3answers
143 views

Peer to peer communication in complicated multi-subnets LAN

We are developing a P2P application and stucked at the part of making communication between 2 peers which are in same local LAN but 2 different subnets. We know that there are a lot of cases that 2 ...
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50 views

Issue Cisco PIM and multicast routing

I'm in the process or redesigning an IPTV headend that is running on mainly layer 2 (IGMP snooping) to layer 3 (Multicast routing using PIM Sparse mode), this will all be done mainly using cisco kit, ...
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2answers
52 views

Who is reached by IP multicast?

We have a piece of software here that seems to be phoning home quite a bit. Using wireshark we figured out that it sends quite a few UDP packets each second to 224.168.168.168. Google tells me, this ...
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44 views

How to route multicast traffic under Ubutun 14.04

I am trying to achieve a very simple goal here, which is to set up a iperf server on my desktop machine to receive any incoming traffic, joe@longbeach:~$ iperf -s -u -B 224.0.0.1 -i 1 ...
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55 views

Is global IP one-to-many communication practical today? [closed]

One-to-many communication over the internet is an enabling technology for many fascinating business and research projects. In principle, IPv4 and IPv6 allow for such communication by the ...
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253 views

Centos. infiniband multicast join failed for status -22

I have a cluster with Linux Centos 6.5 as OS. All the machines are connected by infiniband, the network is working fine but in the /var/log/messages of all the machines I can see the following message ...
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124 views

Multicast destination NAT on same network interface, with netem

For testing purpose, in a big network where IT will shoot me if multicast data are not streamed in the right VLAN, I am trying to degrade multicast packets with a server running netem configuration. ...
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219 views

AWS VPC: Windows server 2012 R2 GRE tunneling to Linux based Peer VyOS

I am asking this question after having spent some time googling and trying to work out some issues which I have with a Windows GRE tunnel in our 2nd environment (amazon AWS VPC) to a router in our ...
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2answers
392 views

pfSense: Cannot filter flood of multicast packets being blocked by default

There are multiple devices under a different subnet on our LAN sending a flood of multicast packets. I've tried to allow this type of traffic, but it does not seem to work.
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1answer
68 views

IPv6: I'm confused about addresses [closed]

I'm starting studying IPv6 and I'm having some troubles understanding some aspects. Let's clarify if I'm getting this right! A single host may have: - a unicast global address - a link local address ...
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1answer
490 views

Receiving multicast traffic on host-only interface

I have a VirtualBox host (linux) with a Windows 8.1 guest. The virtual network configuration for that guest: After disabling auto metric on the host-only Adapter2 (in the guest OS) and fixing it to ...
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222 views

Multicast works only in promiscuous mode

I'm trying to receive MPEG-TS over UDP multicast transport in Arch Linux. So when I run ffprobe -i udp://@224.1.1.240:6000 it hangs forever with no result. Then I run tcpdump and it shows no ...
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1answer
327 views

VPN for Video stream

I work at a digital TV broadcast company (cable), we have 2 head ends, one in the US and one in the Caribbean, we currently connect both sites with a cisco L2TPv3 pseudowire VPN between both sites, ...
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1answer
216 views

How to duplicate multicast packets on several interfaces?

I would like to send a stream from a Linux server to several Linux clients via a multicast address. The clients are directly connected to the server but on different interfaces: bnep0 and bnep1. ...
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149 views

Multicast and duplicate IP addresses

I've developed a Multicast UDP client/server application, which allows a user to remotely change the network configuration of devices belonging to the same multicast group. But what if a device was ...
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277 views

Multicast not working on hp 5820 switch

I have a problem with getting multicast working on hp a5820 switch. I have 4 vlans vlan 1,20,30,40 with layerv3 vlans, I enabled multicast routing and pim dm and igmp on each vlan. On the vlan 1 I ...
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143 views

how multicast stream passes when receiving locally

If suppose I have TX application which transmits UDP multicast to 239.0.0.1:1234. And I have RX application which joins multicast (239.0.0.1:1234), and receives this multicast (239.0.0.1:1234). I ...
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183 views

Does Ubuntu with Linux 3.5 having TX RX ring buffers or BQL

My linux uname -a command outputs: Linux Davinci001 3.5.0-23-generic #35~precise1-Ubuntu SMP Fri Jan 25 17:13:26 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux So, does NICs with this Ubuntu machine is ...
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778 views

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 ...
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151 views

Wifi multicast stream bandwidth limit

i am doing a project with multicast video streaming. The problem i am facing is, in 802.11b and 802.11g WiFi modes the multicast streaming band width is limited to 1Mbps. But the video have a bitrate ...
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69 views

IGMP Snooping limitations and when do you start to use PIM?

At a head end I've just inherited, all our multicast streams run on cisco switches with IGMP snooping enabled. Because all these streams are to be kept local and isolated we've never really looked ...
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309 views

How to use Server 2012 WDS advanced multicast features?

First, can I be clear that I already know how to multicast, and using that without a problem. What I would like to know is... how to use the "Improved Multicast Features" that are new for Server 2012 ...
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175 views

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 ...
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1answer
93 views

What interaction is required for a Windows server and Cisco router to setup and destroy a Multicast session?

I'm trying to understand how Multicast actually works, and have read numerous articles and Wiki pages, and have gathered this: A multicast address takes up state on the router of the membership, ...
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2k views

Keepalived: multicast vs unicast

I'm planning to deploy a several keepalived routers to maintain floating IPs for different database clusters. The plan is to deploy a separate VRRP instance on each cluster locally according to this ...