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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Can FOG and/ or WDS do multicast over an ordinary unmanaged Gigabit Switch? or does it need hardware with specific multicast features?

Can FOG and/ or WDS do multicast over an ordinary unmanaged Gigabit Switch? or does it need hardware with specific multicast features? Trying to help a small non profit in Asia with a poor budget. ...
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40 views

UDP multicast send/receive: Routing or socat issues?

I'm using 'socat' on Linux Centos 7 to diagnose some problems. Server and clients are all linux centos7, they all have multiple interfaces. Server 10.1.1.1 is on Switch 1, 10.1.1.2 is on Switch 2. ...
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2answers
3k views

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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5answers
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Linux Kernel not passing through multicast UDP packets

Recently I've set up a new Ubuntu Server 10.04 and noticed my UDP server is no longer able to see any multicast data sent to the interface, even after joining the multicast group. I've got the exact ...
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2answers
30 views

Office 365 Skype/Lync: Support for stream multicast or mirroring?

Does Skype for Business / Lync when used via the hosted Office 365 service have the ability to do any stream multicasting or mirroring for group meetings? Background: I’m in a branch office with a ...
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1answer
124 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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21 views

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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1answer
636 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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1answer
34 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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100 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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33 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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14 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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66 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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90 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
103 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
10k 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 technique....
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63 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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119 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: 192....
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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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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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23 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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30 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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495 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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39 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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123 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
46 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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74 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 ...
2
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1answer
347 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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0answers
54 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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3k views

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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204 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
58 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
2k 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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338 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 ...
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3answers
154 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
56 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
57 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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48 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
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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0answers
283 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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139 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
438 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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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
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
576 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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0answers
241 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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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 ...