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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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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38 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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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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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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1answer
54 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
175 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
71 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 ...
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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 ...
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1answer
113 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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46 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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2answers
95 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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votes
2answers
98 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
54 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
102 views

Setting up NLB in a VLAN

I have a network layout like this (ESXi hosts): Internal Network + +-----------------+ ...
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0answers
223 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 ...
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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). ...
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0answers
27 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
247 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 ...
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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 ...
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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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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 ...
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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 ...
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2answers
127 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 ...
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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 ...
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1answer
134 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 ...
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1answer
581 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 ...
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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, ...
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0answers
89 views

Send Multicast data to L2TP/IPSec client via PIX/ASA

I know that IPSec doesn't support multicast, but L2TP over IPSec does. My current scenario is: In the corporation internal net, every node can send and receive multicast data without problems. ...
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0answers
84 views

linux kernel configuration to filter multicast traffic based on interface

I have two virtual interfaces (eth0.2, eth0.3) in my PC. I am sending multicast data from eth0.2 to eth0.2. Multicast data is received in eth0.2 but also received in eth0.3, the other virtual ...
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1answer
66 views

How multicasting grouping address works ? How can I add nodes to the existing group of multicasting group? [closed]

I am a newbie to the networking and working on the 6LoWPAN protocol and I am trying to get the multicasting to work on the network. But I don't know how to create group for multicasting and how to ...
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0answers
288 views

How to enable multicast routing in TMG 2010?

I have a TMG 2010 firewall between some office networks, which handles routing and firewalling; I need to let some application-specific multicast traffic flow between these networks; this is UDP ...
0
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0answers
34 views

issue in multicast within VLAN based on interface

Aim : To do audio multicast between VLAN interfaces (eth0.2/eth0.3) in different machines in same VLAN. I have two machines PC1 and PC2, each of which has two VLAN interfaces eth0.2 and eth0.3 I have ...
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2answers
95 views

how to receive MAC multicast packets based on VLAN interface?

can any one pls help me in the following question. Background : Two PC's(PC1 n PC2) with two VLAN interfaces in each (eth0.2 and eth0.3) respectively.The PC's are connected by WRT54GL router in ...
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vote
1answer
191 views

Enable multicast on dummy interface on startup

I have a dummy interface on a Centos 6.3 machine which I would like to use for multicast traffic. The problem is it does not come up with the MULTICAST option by default; I need to manually add it ...
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 ...
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1answer
103 views

If I have a process which is supposed to be receiving data from multicast, how can I check if it actually is?

I can check gstack, but just because I see the listener threads on the recv call does not mean that call is not returning. One other thing I thought was to do something like: netstat -lupe | grep ...
2
votes
1answer
108 views

is there a way to “multicast” a request with haproxy?

I have a configuration with a cloud of servers behind haproxy. Haproxy is loadbalancing between the servers. However there's some action that needs to be sent to each server. Currently I do it ...
2
votes
3answers
3k views

Should I create a multicast route on RHEL/CentOS for a blind sender?

A CentOS 5 system does not appear to come out-of-the-box with a route for multicast traffic. What it does appear to do is use a default route, if configured. In other words, a routing table like ...
0
votes
1answer
93 views

Is multicast appropriate for sending a copy of a video chat to a server?

I am creating a p2p video chat app using the libjingle/WebRTC code. I would like to collect a copy of these video conversations on our server for users to watch later - but I don't want to suck up too ...
1
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1answer
121 views

Does the IGMP querier have to be connected to the multicast source?

I've been reading Allied Telesis' guide on configuring IGMP, which has been quite enlightening so far. However, I'm still wondering whether the IGMP querier has to be connected directly to the ...
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votes
2answers
2k views

Problems with multicasts in “iptables”

My question is related to multicasts and iptables. I want to allow ICMP and IGMP multicasts from the local VLAN 192.168.1.0/24 as well as from 0.0.0.0 on my CentOS machine, so I added the following ...
2
votes
2answers
445 views

Solaris doesn't know which MAC address to use to send an UDP multicast message

I have a pair of Solaris 10 boxes which are supposed to send multicast UDP packets to a group of hosts. One of them works just fine, whereas the other one does not. The problem with the second ...
5
votes
1answer
119 views

Why would I ever (really) want to implement dense mode when dealing with PIM routing?

I'm introducing some PIM routing into my network to make some multicast traffic available across routers. I have read a bit on PIM, sparse mode versus dense mode. After reading, I am trying to ...
2
votes
1answer
92 views

How does iptables determine which packets are multicast?

Are packets assumed to be multicast solely based on their ip address? I've been looking at the RFC 1112 and a quick scan doesn't appear to indicate any other flags on the ip packet.
2
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0answers
160 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
799 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 ...
2
votes
2answers
328 views

MS NLB: why are multicast packets received by all servers on the LAN, not just members of the cluster

I have a MS NLB cluster (Win 2003) which includes just two hosts. The cluster is configured to use Multicast operation mode (not IGMP). For some reason I am seeing packets intended for the NLB ...
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0answers
67 views

How can I set up multicast tunnel between hosts on the same net

Dealing with AWS, where multicast packets won't travel even between systems on the same net (VPC). Generally, this is not specific to AWS, as this is generally possible in any network (i.e. you have a ...