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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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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1answer
2k views

How to monitor a UDP multicast stream on a cisco network, hopefully with SNMP

We have a LAN with 2x Cisco 4500's as gateways running HSRP. We're using Exterity HD IP Encoders to take HD video and put it onto the network as a multicast UDP stream (playable in VLC). I have a ...
1
vote
0answers
228 views

wdsmcast useage and deployment

I'm trying to use WDS multicasting to deploy an image. For some reason I can't get it to connect. Anyone know any guides on how to do this because I followed and few and none are working. I setup a ...
1
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0answers
235 views

Can multiple VLANs be provided with multicast addresses by a single MADCAP server?

Can a single DHCP server provide dynamic multicast addresses for hosts in many VLANs using MADCAP, just like it can provide hosts with unicast addresses via ip-helper? Or from a Cisco perspective, ...
1
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0answers
862 views

Debugging multicast connection over VPN

I'm running Ubuntu 11.10. I have a local application that is trying to receive multicast UDP streams via an OpenVPN tunnel. I have network connectivity to the remote host that is generating the ...
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1answer
741 views

Multicasting Windows 7 Image

I am trying to deploy some new machines with windows 7 for the first time in our computer labs. We used to use third party imaging software and then run sysprep after the image was copied(XP), but it ...
1
vote
1answer
458 views

Reliable Multicast Programming (PGM) on Windows

I want to use the Reliable Multicast Programming (PGM) protocol on Windows. http://msdn.microsoft.com/en-us/library/windows/desktop/ms740125%28v=vs.85%29.aspx I know Windows support it. However, it ...
2
votes
1answer
589 views

What is the difference between bind, network (interface) and multicast addresses?

The DatagramSocketImpl in Java has a joinGroup method that takes a socket address (IP and PORT) plus the interface address (IP and PORT). I am trying to understand the difference and purpose of each ...
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1answer
629 views

VMware ESX 5.0 blocking DHCPv6 solicitations in vSwitches?

We have a network on which we're setting up a test IPv6 deployment. Here's the layout: Win2008R2 DHCP VM and Debian Squeeze radvd VM -> vSphere 5.0 vSwitch -(Trunk)-> Catalyst 2960G -(Trunk)-> ...
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1answer
2k views

NLB Node Participating in Cluster But Not Listed in Manager

I have a NLB cluster that has been setup for several months and everything is working as expected. After a reboot of one of the nodes I no longer see that node in the NLB manager. It says it's ...
2
votes
2answers
10k views

What does this linux command mean “route add -net 224.0.0.0 netmask 240.0.0.0 eth0”

Could somebody explain what exactly this command means in relation to transmitting and receiving multicast traffic route add -net 224.0.0.0 netmask 240.0.0.0 eth0
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5answers
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Convey multicast (to another LAN) through WAN disabling multicast

My Server and Client softwares run both on Linux. The Server broadcasts multicast, the Client listens multicast. My Client has to migrate to another site, and unfortunately multicast is not allowed ...
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votes
2answers
3k views

Multicast routing across two subnets with FreeBSD 9 (Bonjour between subnets)?

I have a FreeBSD 9 router (a Soekris net6501) connected to the internet via a dsl modem (bridged), doing NAT for two internal subnets, 10.0.1.0/24 (LAN) and 10.0.2.0/24 (wifi net). There are routes ...
2
votes
1answer
898 views

altnet parameter into pimd.conf file

I need to route a multicast streams in my private network. I'm using pimd for multicast routing. The multicast routing did not work until I put altnet <multicast_source_ip> masklen 24 to the ...
2
votes
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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0answers
289 views

Can I Override Multicast Address for One Specific Destination IP?

I have a Windows XP machine that is fitted with two Network cards. One card is used to access the company network and internet and its IP is assigned by DHCP whilst the second has a fixed IP and is ...
2
votes
2answers
1k 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 ...
3
votes
1answer
176 views

Server Unresponsive with Spike in Multicast Packets Received

I got a server from UbiquityServers about a week ago, I installed a simple Apache server and it just serves up images. The server is under very little load because it simply is an origin server behind ...
2
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1answer
1k views

IGMP V3 support in Linux-2.6.35

I am trying to start a bridge connection and force it to use IGMPV3. The following command will explain my issue better : The below is the output of force_igmp_version before issuing brctl commands ...
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2answers
5k views

multicast routing - CentOS 5

I'm trying to pass mulitcast stream from interface eth1 (192.168.20.41) to interface tun0 (192.168.100.40) on CentOS 5. I can see incoming multicast stream on eth1: tcpdump -n -i eth1 type=1700 ...
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1answer
451 views

Catalyst 3560G SPAN session not mirroring IGMP packets

I am developing a device which acts as a multicast host, and want to observe it as it responds to IGMP Queries. My Catalyst 3560G is set up as follows (full config below): Port 0/1 is a TFTP server ...
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1answer
6k views

multicast and iptables : troubleshooting?

I have secured a linux box, starting with iptables -P INPUT DROP iptables -P OUTPUT DROP iptables -P FORWARD DROP and after adding rules to enable specific protocols and streams. Which are the ...
5
votes
1answer
193 views

ntp multicast address

A silly question probably, but guess I need to ask. If I've got four centos boxes that are acting as ntpd multicast servers, will the multicast address configured in each box's ntp.conf all be the ...
2
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2answers
5k 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
487 views

How to send multicast traffic from one vlan to 100-500 other

In addition to prev question How to share multicast traffic to many vlans I recieve answer that solution for my task is mrouted on my freebsd router. But for now i see this problems: mrouted ...
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1answer
1k views

Multicast with wifi access points

Using 2 consumer grade access points what is the behavior of when multicast packets are sent between them. Consider -> AP1 -> AP2 (Note that AP1 & AP2 are connected over the LAN ports to the ...
1
vote
1answer
668 views

How to share multicast traffic to many vlans

I have linux computer , this computer connected with entire my network via zyxel gs-2200. In this zyxel also connected router with 500 vlans, one by client. On linux computer i have vlc program ...
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2answers
2k views

virtualization with multicast receive

I need a virtualization solution with the following properties: guest OSes can receive multicast traffic from the host machine. some services running on the guest OS (eg: port 80) can be port ...
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 ...
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0answers
1k views

Problems with multicast under Mac OSX Lion

We have been developing our Java applications under OSX for some time. Since switching to OSX Lion (version 10.7.1 now), we see sporadic issues around multicast packets going into the bit bucket and ...
0
votes
1answer
92 views

Can I use routes to influence which interface address multicast listeners use?

I have a server with multiple NICs on it. Each NIC is plugged into a different, isolated network that is serving multicast traffic. I have a program that listens to the multicast traffic on each of ...
3
votes
4answers
956 views

Is there a good way to keep IPv6 multicast packets off WiFi?

I work on a product that consists of a number of headless Linux boxes that work together as a cluster. These boxes synchronize their state with each other by sending proprietary-format link-local IPv6 ...
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0answers
3k views

UDP Multicast not working without promisc. Already tried rp_filter=0

I'm having issues with multicast traffic in Ubuntu Maverick. It only appears to work when the card is in promisc mode (i.e. if I set it manually, or use a tool such as tcpdump). Adding multicast ...
5
votes
4answers
4k 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 ...
7
votes
1answer
2k 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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vote
0answers
3k views

Can't get multicast to work (iperf)

I have some problems to get SLP (service location protocol; I play around with the OpenSLP implementation) to work. It uses multicast on 239.255.255.253, port 427. To narrow down the problem I decided ...
8
votes
4answers
25k views

How can I test Multicast UDP connectivity between two servers?

I have two servers on the same subnet. I have an application installed which uses multicast UDP to propagate events between the two servers and keep them in sync. This does not seem to be happening, ...
0
votes
1answer
711 views

NLB Traffic Stops on all nodes when a single node is rebooted

We had a 2 node NLB cluster running IIS websites on virtual machines. Both nodes were online, the balancer functioned exactly as expected, (if traffic is 50/50 balanced, and you stop or drainstop a ...
6
votes
1answer
2k views

Multicast hostname lookups on OSX

I have a problem with hostname lookups on my OSX computer. According to Apple's HK3473 document it says for v10.6: Host names that contain only one label in addition to local, for example ...
43
votes
3answers
64k 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
2answers
5k views

How managed switches handle Broadcast Multicast and Unicast?

Under typical scenarios, a network switch needs to handle broadcast, multicast and unicast messages at the same time. I'd like to understand On a typical managed switch (1Gb Ethernet/10Gb Ethernet), ...
9
votes
1answer
389 views

Simple Multicast Design

In order to support desktop imaging requirements I need to correct the multicast design on an existing network, but am not well versed in this subject. The diagram below gives a basic example of the ...
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0answers
727 views

Multicast Default Interface - upgrade to RH5.5

I have upgraded a server from RH4 -> RH5.5 and we have an interesting issue with multicast. we have multiple NICS on the server, we want the bond0 to default as the default interface. adding route ...
4
votes
1answer
13k 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.
2
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2answers
453 views

Multicast IP Addresses

I posted this on StackOverflow and was told it might be more appropriate here. I'm having trouble understanding how multicast addresses work. First off, is it true that if I have N clients or peers ...
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vote
4answers
7k views

Unicast to multicast via iptables

Note: While there is an accepted answer now, it is only part; check the final iptables rule below. I'm receiving a unicast RTP stream on one interface and wish to send it out via multicast on a ...
0
votes
2answers
745 views

looking for multicast traffic

We have a j2ee webapp on tomcat which is using ehcache with multicast discovery. Except it's not discovering anything. There appears to to be no multicast traffic visible on the network but we're a ...
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2answers
1k views

In what kind of environment multicast is not preferred?

While reading a product documentation I came across a line in which they say product supports TCP communication in environments where multicast is not available or preferred. Why would a company ...
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1answer
2k views

Stateful matching of multicast responses in iptables

A central part of my firewall configuration is: -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT It seems that RELATED does not work for multicast responses: when the host sends to a ...
0
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1answer
277 views

SNMP OID to get multicast bytes

Right now I can only find oid for ifInMulticastPkts and ifOutMulticastPkts, but there is no bytes information. Can anyone know about this? thanks in advance.