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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Unable to ping multicast IP

Let me prefix this by saying I'm not entirely clear on how multicast works. I have the gist of it, but not the underlying functionality. A customer has configured a RHEL6 cluster between two Jboss ...
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1answer
2k views

How to make sysctl network bridge settings persist after a reboot?

I am setting up a notebook for software demo purpose. The machine has 8GB RAM, a Core i7 Intel CPU, a 128GB SSD, and runs Ubuntu 12.04 LTS 64bit. The notebook is used as a KVM host and runs a few KVM ...
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1answer
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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64 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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16 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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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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60 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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26 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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1answer
62 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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1answer
9k views

Wireless Multicast Forwarding on OpenWRT

Good day! We need to connect an STB device over wi-fi to the router. STB uses multicast only. Using udpxy is not possible. Original firmware forwards multicast over wi-fi using mac changing ...
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51 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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81 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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1answer
1k views

Create NSC-File for multicast streaming with Windows Media Streaming

For streaming multicast I need to create a NSC-file for the players - this file is pseudo-coded by Microsoft. Now I need to create this file for each proxy-publishingpoint. Is there any way to stream ...
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1answer
83 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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3answers
2k views

Troubleshooting UDP multicast on Windows

I'm a programmer, not a system adminstrator, so please forgive my administrative naivete. My software, written in C#, relies on UDP multicasting. One machine, the server, streams events to an known ...
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21 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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24 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 ...
2
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0answers
262 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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30 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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0answers
65 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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1answer
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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59 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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0answers
488 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 ...
2
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1answer
331 views

Manual Multicast forwarding with Linux router

I have a Linux router (Ubuntu). It is working well with unicast but with multicast routing/forwarding I have some trouble. The problem is that my hosts do not send igmp/mld messages thus the router ...
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42 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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6answers
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Is IPv6 multicast routable over the Internet?

As I understand it, public IPv6 addresses allocated by the IANA will have the prefix 2000::/3. These ip addresses will be routable through the Internet. IPv6 multicast addresses on the other side are ...
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1answer
171 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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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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1answer
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
1k views

Cisco 3560+ipservices — IGMP snooping issue with TTL=1

I've got a C3560 with Enhanced (IPSERVICES) image, routing multicast between its VLANs with no external multicast router. It's serving a test environment where developers may generate multicast ...
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0answers
250 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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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 ...
2
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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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0answers
49 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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0answers
43 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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0answers
54 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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0answers
248 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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0answers
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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2answers
388 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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216 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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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 ...
2
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1answer
2k views

How to setup a static multicast ARP entry with Cisco SG300?

We're running a Microsoft NLB cluster in multicast mode as a loadbalancer. Using our old Cisco IOS switches we propagate access to the cluster to our branches using a static ARP entry in the core ...
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1answer
480 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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220 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
1k views

Lot of Multicast traffic on LAN

Recently the whole network at work is being hit by multicast traffic originating on the LAN itself. I did some investigating and the service which seems to be responsible is ws-discovery. I have ...
23
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4answers
2k views

Pushing Large Files to 500+ Computers

I work with a team to manage 500-600 rented Windows 7 computers for an annual conference. We have a large amount of data that needs to be synced to these computers, up to 1 TiB. The computers are ...
2
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1answer
326 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
501 views

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 ...
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1answer
214 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. ...