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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57 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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12 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
22 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. ...
3
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2answers
120 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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1answer
749 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
709 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 ...
5
votes
2answers
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
1k 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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0answers
39 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
28 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
843 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 ...
0
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1answer
20 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
57 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
181 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 ...
2
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1answer
5k 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.
3
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1answer
73 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 ...
26
votes
3answers
22k 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 ...
5
votes
1answer
985 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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votes
1answer
65 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 ...
5
votes
4answers
10k 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, ...
1
vote
1answer
116 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 ...
0
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0answers
47 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: ...
5
votes
5answers
1k 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 ...
0
votes
2answers
97 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
99 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
55 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
votes
1answer
102 views

Setting up NLB in a VLAN

I have a network layout like this (ESXi hosts): Internal Network + +-----------------+ ...
0
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0answers
225 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
votes
0answers
210 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
votes
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 ...
0
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0answers
28 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 ...
1
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1answer
253 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
229 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 ...
0
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0answers
73 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 ...
1
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0answers
52 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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vote
0answers
89 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 ...
0
votes
0answers
69 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
votes
2answers
128 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 ...
13
votes
5answers
14k views

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 ...
4
votes
4answers
3k views

Multicast File Transfers

I'm looking for some multicast file transfer software. Do you have any suggestions? Must be "quickly implementable", i.e. no Tivoli or other stuff that requires a massive infrastructure. Must run on ...
0
votes
2answers
35 views

unicast traffic on windows server

I have three servers with IP addresses (10.15.23.23, 10.15.23.24, 10.15.23.25). Server 1 and Server 2 have Tomcat installed and are configured as a cluster listening on a multicast IP address ...
21
votes
4answers
866 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 ...
1
vote
1answer
247 views

Multicast File copy with Unicast responses

I'm trying to do some multicast big file copies over to remote clients on the other side of a satellite link. The idea is to minimize the amount of traffic going up to the satellite. I tried using ...
1
vote
3answers
2k views

Windows Network Load Balancing on ESX Cluster with Dell PowerConnect stacks

We recently switched out our Cisco 6500 core switch for a pair of Dell PowerConnect 6248 stacks. Since then, our Network Load Balanced Sharepoint, which runs on two virtual machines on an ESX cluster ...
1
vote
1answer
749 views

How do I enable multicast routing in Windows XP

I have successfully set up a Windows XP machine as an IPv6 router using netsh, that is, it announces prefixes and forwards packets on two interfaces, as verified by pinging. Now I'd like to forward ...
0
votes
1answer
135 views

diagnostic multicast issue using wireshark

I have a network that is setup for multicast traffic. My setup is the following -Machine A : a server generates multicast traffic. -Machine A : few clients subscribing to that multicast traffic ...
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0answers
46 views

Discovery of computer behind router from behind another router

I'm trying to simplify our systems by creating an automatic discovery solution. On a network we have little to no control over, except for some basic requirements, we want Computer 1 to dynamically ...
0
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1answer
587 views

Multicast Listener Report Message v2

I run an ICMPv6 protocol and I have made a capture using wireshark. In the capture I have some Multicast Listener Report Message v2. Some of the has the source ip, the ipv6 link local address, but ...
0
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1answer
72 views

DNS resolution on multicast IP

Edit: Looks like ns lookup on some mcast IP doesn't not get a failed answer right away. Any suggestion? I have two env, the new one we built is running BIND on linux. When running lsof or tcpdump, ...