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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2answers
304 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 ...
0
votes
1answer
34 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 ...
1
vote
1answer
87 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 ...
4
votes
5answers
167 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 ...
0
votes
1answer
112 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 ...
2
votes
1answer
647 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 ...
1
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0answers
51 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) ...
3
votes
2answers
494 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
2k 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 ...
0
votes
1answer
249 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 ...
0
votes
2answers
169 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 ...
1
vote
1answer
466 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 ...
3
votes
1answer
8k 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 ...
3
votes
1answer
1k 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 ...
-2
votes
1answer
79 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 ...
1
vote
1answer
700 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
votes
2answers
756 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 - ...
-1
votes
2answers
263 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 ...
2
votes
1answer
448 views

Setting up NLB in a VLAN

I have a network layout like this (ESXi hosts): Internal Network + +-----------------+ ...
1
vote
1answer
1k 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 ...
1
vote
0answers
209 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 ...
1
vote
0answers
282 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
2answers
373 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 ...
0
votes
2answers
36 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 ...
0
votes
1answer
608 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 ...
0
votes
1answer
2k 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
votes
1answer
229 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, ...
1
vote
0answers
211 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 ...
-1
votes
1answer
109 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 ...
0
votes
0answers
773 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 ...
-1
votes
2answers
382 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 ...
1
vote
1answer
474 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
730 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 ...
1
vote
1answer
555 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
404 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 ...
3
votes
3answers
8k 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
144 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 ...
2
votes
1answer
245 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 ...
0
votes
2answers
5k 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
891 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
190 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
154 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
votes
1answer
306 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 ...
1
vote
2answers
2k 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
905 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 ...
1
vote
0answers
156 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 ...
0
votes
1answer
484 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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1answer
47 views

Motorolla TeamBadge Issue [closed]

I have A setup of Motorolla EBW100 Team Badges (typical Walkie Talkie). My wifi is configured as Such that it has Multiple SSIDs For different Badges. Like in Floor A I want 10 Team Badges to work ...
2
votes
0answers
302 views

network leave/unscribe multicast group

I have debian based server where I need to subscribe a multicast. After doing it with headless mpalyer I can see the following: root@ca1:~# netstat -g IPv6/IPv4 Group Memberships Interface ...
1
vote
1answer
1k views

IP-Multicast difference between 224.0.0.1-255 and 239.0.0.0/8 block

Whats the difference between: Local subnetwork Addresses in the range 224.0.0.0 to 224.0.0.255 are individually assigned by IANA and designated for multicasting on the local subnetwork only. ...