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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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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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 ...
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4answers
39k 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, ...
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1answer
828 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
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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 "My-...
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3answers
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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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2answers
6k 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
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1answer
402 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
818 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 ...
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1answer
20k 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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2answers
560 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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4answers
9k 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 ...
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2answers
788 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
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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
306 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.
0
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1answer
2k views

Cisco 3560+ipservices — IGMP snooping issue with TTL=1

I've got a C3560 with Enhanced (IPSERVICES) image, routing multicast between its VLANs with no external multicast router. It's serving a test environment where developers may generate multicast ...
5
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1answer
1k 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
2k 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
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1answer
684 views

Multiple network interfaces and UDP packets distribution

I have a Linux server with 2 1Gb network interfaces eth1 and eth2. If I start 2 clients listening to the same multicast address and each client connects through a different NIC (say client 1 listens ...
0
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1answer
490 views

Multicast NAT on Juniper router

I am trying to do source NAT on a J-series router (junos 9.2). I have two separate NAT rules setup (using security policies + source-nat interface). One is for regular unicast TCP connections and the ...
2
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1answer
1k views

openSUSE 11.3 multicast IGMP v2 works on one vlan, but not the other vlan

I have a server running openSUSE 11.3, with vlan5 and vlan40 configured on eth7. I want to join two multicast IGMP v2 groups, one on vlan5 and one on vlan40. When I send out the IGMP v2 Membership ...
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3answers
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Basic multicast network performance problems

I've been using mpong from 29west's mtools package to get some basic idea of multicast latency across various Cisco switches: 1Gb 2960G, 10Gb 4900M and 10Gb Nexus N5548P. The 1Gb is just for ...
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4answers
2k views

Should a small company block multicast on their network?

Currently, the firewall at a small company is blocking multicast on their network. Should they continue to block multicast? Are there security concerns to unblocking it? Are there benefits to ...
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5answers
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Tools to test multicast routing [closed]

I am looking for a good simple tool that runs on a standard OS (Windows or Linux) that I can used to test that multicast is being passed properly by a router. I have been asked by a client to enable ...
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2answers
3k views

Multicast over SSH

I have two LANs: 10.x.x.x and 192.x.x.x. On each LAN I have a Linux machine (10.x.x.5 and 192.x.x.5) but they are not routers. I can open ssh from 192.x.x.5 to 10.x.x.5. There are multicast udp ...
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1answer
20k views

How do I add a multicast route in Windows 7?

I have 2 interfaces on my desktop: one in a multicast enabled vlan, that has access to some udp streams, but otherwise unrouted, and one with internet access, but no multicast. If only the multicast ...
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2answers
490 views

Multicasting for WDS

I want to install a Windows 7 image on 40-something computers without touching 'em I have a WDS server, an image captured, and an answer file setup. I go to create a multicast transmission out of ...
0
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2answers
292 views

Unicast through Multicast

Suppose I have Multicast group with a group ID and I want to send packet to only one of the group members(as we are doing in anycasting). Is it possible? If yes then how?
2
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1answer
167 views

Multicast over 802.11b wireless

How do wireless routers behave with regards to multicast traffic? Given that nature of the shared physical medium routing to specific ports is not possible. Therefore, are mutlticast packets ...
3
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2answers
2k views

IGMP/Multicast routing in Linux

I need to route IGMP/Multicast traffic across two networks. I have a Linux box with two NICs, one public, one private. Need devices on the private network to flow to public. I'm pretty certain I ...
1
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1answer
402 views

Windows Deployment workflow

I've been digging around and getting WDS, WAIK, and the Deployment Workbench all configured and installed on a server we'll be using to roll images out to classrooms. I want to make sure I understand ...
1
vote
1answer
278 views

How to get UCARP to work over wireless?

I would like to get ucarp to work over a wireless (802.11g) interface, but the packages is never seen on the wired end. The setup looks like this: Box1 (10.0.0.11, wireless) -- AP -- (10.0.0.13, ...
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2answers
402 views

How to restore with multicast 3 systems: Windows 7, Windows 2008 and Linux?

We have used an old version of Norton Ghost to do backups and restores of computers. There are few groups of computers with the same hardware and we have used multicast. We have had Windows XP, ...
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2answers
944 views

Selecting interface for multicast traffic?

How do I specify an interface for multicast traffic? I need to connect to multicast group through vlan interface (tcpdump show traffic there) but I believe that IGMP request are sent throug eth0. ...
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4answers
6k 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 ...
2
votes
3answers
1k views

Why are my listener-less multicast packets affecting Wifi performance?

I've got a program that sends out a IPv6 multicast packet (to ff12::2:0:8afb:382b:c053:85f%en1) every 50ms. I've got it running on a very simple single-computer LAN (Mac mini <-wifi-> Linksys wifi ...
0
votes
1answer
640 views

JBoss without multicast?

Does anyone know if it is possible to run JBoss as a cluster using only unicast, no multicast? More importantly, does anyone have experience actually getting this to work?
24
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5answers
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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 ...
2
votes
1answer
480 views

Clustering on cloud/VPS providers

I'm wondering if anyone can give some clustering recommendations to me. I'm currently on Linode, which I'm impressed and happy with, but they (along with just about every other VPS provider I know of) ...
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1answer
1k views

Lots of artifacts while streaming HD content with VLC 0.9.9 on CentOS

I'm trying to stream (multicast) a x264 encoded file using VLC. This in itself succeeds, but the stream has a huge lot of artifacts. This seems to suggest that the data cannot be transported fast ...
2
votes
1answer
1k views

Multicast accross the subnets

My application sends some UDP packets on a multicast address. In our office we have 3 subnets connected via routers. Sitting in my subnet I'm able to ping the IP of the other subnet. Will multicast ...
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2answers
1k views

Multicast image restoration with adaptive speed

I'm curious to know if there are any tools for restoring disk images (or even transferring files) via multicast -- for any platform, especially if the project has source available -- where the ...
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2answers
483 views

video streaming infrastructure advice

We would like to set-up a live video-chat web site and are looking for basic recomendations for software and hardware set-up. Here are the particulars on the site: Most streams will be broadcast ...
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1answer
1k 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 ...
0
votes
2answers
425 views

UPD Multicast (Class D) = How can this be routed over the internet?

is there a simple way (without setting up a local network via VPN) to route UPD Multicast Packets (224.0.0.0 to 239.255.255.255) from one server to another server (both residing in completely ...
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3answers
3k 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 ...
4
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1answer
178 views

Calculating and billing IP multicast usage on the Internet

I've been searching for the reasons why IP multicast isn't widely supported on the Public Internet, and a commonly-cited reason is the difficulty ISPs have in tracking Multicast usage for later ...
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1answer
1k views

Confusion about HSRP Groups

If I have a router that has several LANs on it, and each of these LAN is attached to a second router, do I need to use different HSRP groups for each LAN? With this set up, each virtual gateway will ...
3
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1answer
5k views

How DNS service discovery, multicast DNS and Bonjour are related?

I am a bit lost in the terminology. I wanted to start to use Bonjour. As the first step, I tried to find an easy way to use it. And I thought that I, probably, can call Bonjour from the command line ...