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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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
826 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 ...
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1answer
779 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
25 views

Possible to emulate an IGMP querier in software?

In the absence of an IGMP capable router, is it possible for the multicast source itself (or any other host, for that matter) to assume the router's role and send IGMP queries etc. so that (IGMP ...
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1answer
64 views

How can my server announce its presence to everyone in the network [closed]

The situation is as follows. I want to have an application running on a server. All of the desktops in the company has to connect to it. But I do not want the IP address of the server to be hard coded ...
2
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1answer
32 views

tcpreplay throughput on eth0 well below (iperf confirmed) max

I'm trying to replay captured UDP multicast packets at a rate of a couple of hundreds of Mbps, but it maxes out at about 86 Mbps. (For some strange reason, at other times during the day it ...
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1answer
783 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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1answer
23 views

Odd multicast messages during IPv6 autoconfiguration

So I am trying a little autoconfiguration on some virtual machines while observing what happens in wireshark and trying to understand what how it works, step by step. This is how any of those ...
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11 views

Redirecting locally generated IP multicast over a GRE interface [duplicate]

On a linux box, I want to redirect locally-originating IP multicast traffic (OSPF hello) over a gre tunnel interface. How can I do this using iptables rules?
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2answers
3k views

multicast tcpdump and subscriptions

From the multicast howto: IP_ADD_MEMBERSHIP. Recall that you need to tell the kernel which multicast groups you are interested in. If no process is interested in a group, packets ...
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1answer
249 views

Icecast2 and multicast

Does anyone know if Icecast2 supports multicast? I've been searching for a while and I found nothing on neither docs or FAQ Thanks
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16 views

PIMD daemon needs long time to send PIM join message

I am using the PIMD daemon on Ubuntu Server 12.0.4 (32-bit). When it receives IGMPv2 membership report for certain group, it takes sometimes two, sometimes five seconds to send PIM join message to its ...
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1answer
23 views

How to set up custom multicast address

What would it take to setup a custom made multicast ip address in the network? Machines are linux. Let's say I want to have a multicast address with only some machines from the network as group ...
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1answer
34 views

Window 7 source-specific multicast (SSM)

We are planning to stream video feeds over multicast to managed Windows 7 devices. Does Window 7 support source-specific multicast at the OS layer (as the receiver)? It appears that XP and Vista both ...
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5answers
105 views

send files to dozens of servers quickly

We have a cluster of machines (around 50 and growing). Each machine has a search index that needs to be updated multiple times per day. We currently update the index on each machine individually, but ...
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4answers
1k views

Capturing multicast data with Wireshark with IGMP Snooping Enabled at the switch

I am trying to capture multicast traffic via Wireshark (actually TShark), however the switch has IGMP snooping enabled and will only send Multicast traffic on the ports that have an active IGMP ...
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1answer
237 views

Ubuntu 14.04 Ipv6 multicast

I having troubles to setup an IPv6 multicast server with Ubuntu 14.04, the server fails with Invalid argument when try to bind to IPv6 multicast address, checked with mcfirst tool and got the same ...
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0answers
22 views

ospf hello not forwarded

I am trying to change the destination ip of ospf hello packet (224.0.0.5) to link local address using iptables rule (DNAT) . It does not seem to work. A similar rule for unicast packet (BGP control) ...
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0answers
45 views

Why are my multicast packet discarded?

I have two boxes and I have some issues when tcpreplaying a pcap full of multicast from one machine to the other. I see the packet incoming on the destination machine thanks to a tcpdump instance. ...
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2answers
168 views

Split multicast traffic on two vlans using IOS

Here is what I want to do: On a switch / router running cisco IOS ( Ideally it would work on a Lanbase image on a 3560G but it is possible to use 65xx routers also ) I receive two udp multicast ...
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0answers
124 views

Multicast route setup for multiple interface

Currently I have the below eth5 to receive multicast data for 239.1.1.31. It works. $ ifconfig eth5 Link encap:Ethernet HWaddr E4:11:5B:94:E1:F3 inet addr:10.185.2.2 ...
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2answers
56 views

Multicasting on server with bridged interfaces

Network: 10.1.1.2 and 10.1.1.3 in same network. 10.1.1.2 has VPN server running in bridged mode. 10.1.1.4 - ip address of VPN client. All machines have Debian 6 installed. I'm trying to test ...
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2answers
1k views

How to disable multicast on a single port

We just finished deploying 2 cisco SG300-28 switches in our network. We're building a voLANte video distribution network, so all ports were enabled to have multicasting support. The problem we face ...
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1answer
39 views

Cisco ASA IPSec VPN - service discovery (e.g. shared folder browser)

We have an ASA 5505 doing IPSec VPN for remote users. Client access is working almost as expected:clients can reach hosts on the internal LAN, even using DNS, and we are tunneling all client traffic ...
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1answer
119 views

Many 'Deny IPv6-ICMP reverse path check' alerts from multicast addresses on Cisco ASA

In an effort to prevent IP Source Address Spoofing (RFC 2827) I've enabled reverse path filtering (RPF) on my Cisco ASA 5505. The topology is aprox. like this. Each segment has its own IPv4 subnet ...
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1answer
6k views

How do I know if IP Multicasting is enabled on my network in Windows?

How do I know if IP Multicasting is enabled on my network? It is same question as above but for windows.
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1answer
127 views

Should IGMP Snooping be configured on all Layer 2 switches on LAN?

We've used Multicasting for the first time in one of our applications and whilst I have got it working, I'd really like to fully understand how it works and what's going on behind the scenes. In an ...
28
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3answers
25k views

What is the difference between unicast, anycast, broadcast and multicast traffic?

I have never had the privilege of working in an environment that required complicated routing or if it did require it, it was handled upstream of me. I've always used very simple static routing ...
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1answer
1k views

windws server 2008 udp multicast performance problem

I encounter a strange performance problem on 2008 R2 Enterprise SP1. Here is the setup: Many processes listening to distinct Multicast UDP streams (5 multicasts listen by process) bound on a single ...
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1answer
67 views

why does a multicast server endlessly transmitting packets even no client require [closed]

i used to setup a multicast server using windows server 2003 OS, i can see a lot of packets transimitted from the server once it was started. Does it make sense when no one is requiring the multicast ...
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4answers
12k views

How can I test Multicast UDP connectivity between two servers?

I have a two servers on the same subnet. I have an application installed which uses Multicast UDP to propagate events between the servers and keep them in sync. This does not seem to be happening, ...
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1answer
198 views

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 ...
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78 views

Clonezilla SE Multicast Issues

This is my first go-around with Clonezilla SE. I have it on it's own, private, network where the server is also serving DHCP to the machines that join the network. Server: Dell Optiplex 790 (SFF) OS: ...
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5answers
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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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2answers
161 views

Running WDS with multicast enabled from within a Hyper-V cluster

I'm attempting to run a multicast installation with WDS over my network, where WDS is hosted in a virtual machine in a Hyper-V cluster. I believe we've paved over most of the network-related issues - ...
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2answers
105 views

What is the equivalent of 127.255.255.255 for OS/X machines so I can test broadcast udp packets without a network? [duplicate]

I am trying to test my program that makes use of broadcast UDP (not multicast!). In Linux, I can use the 127.255.255.255:64651 address and everything works beautifully, in other words, I send a packet ...
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0answers
86 views

How does the “Use IP address from the following range” option work in WDS?

I'm currently in the process of learning how I can setup a multicast session for installing several clients with the same image via Windows Deployment Services. I have been looking at the "Use IP ...
2
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1answer
134 views

Setting up NLB in a VLAN

I have a network layout like this (ESXi hosts): Internal Network + +-----------------+ ...
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0answers
279 views

Tomato RT-N16 - How to Prevent Multicast Packets from Reaching OpenVPN clients (TAP)

We have a remote (like in the woods) client using a VPN connection to connect to our office, using this link we can monitor and operate the remote client without a few hours drive in the wild. This ...
0
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0answers
230 views

How can I redirect/forward all the UDP/TCP traffic on one interface to another interface in OpenWrt

I am new to networking and I have a measurement device (D) that periodically sends all its readings over few UDP multicast sockets (with different multicast IP addresses and different port numbers). ...
3
votes
4answers
1k views

Multicast in Rackspace cloud

On Amazon EC2, I cannot use multicast, but how about rackspace cloud? It would be very beneficial to be able to use multicast as most clustering protocols rely on it...
7
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1answer
2k views

iperf max udp multicast performance peaking at 10Mbit/s?

I'm trying to test UDP multicast throughput via iperf but it seems like it's not sending more than 10Mbit/s from my dev machine: C:\> iperf -c 224.0.166.111 -u -T 1 -t 100 -i 1 -b 1000000000 ...
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0answers
41 views

Multicast loopback under OpenVZ?

I'm trying to configure an OpenVZ container to allow sending/receiving multicast on the loopback interface. I've done this: ifconfig lo multicast route add -net 224.0.0.0 netmask 240.0.0.0 dev lo ...
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1answer
349 views

How to make a Cisco AP1142N speak Bonjour?

I have an autonomous Cisco access point (model AP1142N) and an Apple TV that are on the same physical and logical network. Bonjour does not work across the access point — both WiFi-to-WiFi and ...
2
votes
3answers
277 views

Why would IGMP and MLD be required to forward unregistered packets to all ports?

First, a little background: My understanding is that the purpose of IGMP (and its IPv6 cousin, MLD) is to avoid wasted bandwidth by ensuring that multicast packets only get transmitted to ...
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0answers
83 views

Net-SNMP Equivalent to netstat -g

I'm working on a project where it's necessary to determine the multicast groups that several Linux servers are subscribed to. While I know that you can easily get this by running netstat -g, one of my ...
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0answers
57 views

ARP Tables on Windows vs Linux

I noticed on Windows Server 2008, Windows Server 2008 R2, and Windows 7 that IP multicast groups joined by a computer are recorded in the ARP table as static addresses automatically. However, the same ...
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0answers
103 views

How do get multicast to work on a Cisco AP1240?

I have a Cisco AP1142N in standalone mode acting as a simple AP. On the wired segment of the LAN, there is an Apple TV that is used to mirror laptop screens to a large TV screen. As long as clients ...
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0answers
95 views

Libvirt/Qemu - Host cannot receive guest multicast

I'm attempting to setup multicast communication between a host and multiple guests. The guests can both send and receive all multicast messages from any guest and the host. However, the host cannot ...
0
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2answers
153 views

Can heavy UDP traffic create network congestion?

I have three IP addresses using the same gateway. Two of them are configured as a cluster with multicast address setup. If there is a heavy UDP traffic between those two, can that affect the network ...