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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298 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 ...
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3answers
396 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
221 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 ...
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1answer
213 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
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3answers
5k 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 ...
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1answer
116 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
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1answer
164 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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2answers
3k 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 ...
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2answers
618 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 ...
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1answer
149 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
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1answer
98 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.
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198 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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1k 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
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2answers
493 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
89 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 ...
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1answer
313 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 ...
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0answers
178 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 ...
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1answer
639 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. ...
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1answer
472 views

Multicast in private LAN with different subnets

after i read Multicast IP Addresses and Multicast accross the subnets I am confused. Configuration: I have two devices in the same network. They may not be in the same Subnet, but ...
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2answers
2k 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 ...
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4answers
1k 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 ...
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0answers
1k views

How to make sysctl network bridge settings persist after a reboot?

I am setting up a notebook for software demo purpose. The machine has 8GB RAM, a Core i7 Intel CPU, a 128GB SSD, and runs Ubuntu 12.04 LTS 64bit. The notebook is used as a KVM host and runs a few KVM ...
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1answer
315 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 ...
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1answer
3k views

Multicast doesn't seem to be working on RHEL 5.5

I'm trying to install Oracle Grid Infrastructure on two machines. Their documentation states: You must enable multicasting for the cluster on the IP address subnet ranges 224.0.0.0/24 and ...
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1answer
222 views

multicast streaming, too much network traffic?

I am thinking of switching our streaming servers to use multicasting instead of registering multiple clients and duplicating the streams manually on the server. It seems to work very well. However, I ...
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2answers
2k views

Can I test broadcast packets on a single machine?

I want to have a server sending broadcast UDP packets and two other clients, in the same machine, receiving them. Can I do that somehow? What IP address would I use? @gravyface gave me hope but I ...
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1answer
4k views

Why is pfSense blocking multicast traffic when it is explicitly enabled?

I have a pair of pfSense firewall/routers set up in CARP/XML Config cluster. On the LAN side, the switch also has a pair of servers running corosync/pacemaker/drbd. These are on a different ip ...
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3answers
911 views

Is there Muticast routing support on a Cisco 3750?

We have a switch (Cisco WS-C3750G-48TS) with only a C3750-IPBASE-M image (not a 'C3750-IPSERVICES-M' license). Is there any kind of multicast support here? All I need it to do is route multicast ...
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1answer
174 views

multicast network based on bridges between two hardware servers

+------------------------+ Internet +----------------------+ | Server_1 | | | Server_2 | | VPS1 ---- br0 __ | (router) | __ VPS4| ...
3
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1answer
83 views

Streaming root/source in multicasting sparse mode

I'd like to verify if I understand multicasting correctly. In a pim sparse-mode configuration, the RP rtr becomes the "root" of the stream for the rest of the configured routers. Does this mean that ...
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5answers
2k 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 ...
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1answer
1k 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 ...
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0answers
189 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 ...
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0answers
200 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, ...
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0answers
751 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
654 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 ...
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1answer
349 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
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1answer
453 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
572 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
1k 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
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2answers
6k 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
842 views

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 ...
4
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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
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1answer
727 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 ...
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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
263 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
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2answers
998 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
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1answer
153 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 ...
1
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1answer
829 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 ...