Questions tagged [multicast]

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 it.

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Change network interface for multicast subscription

My laptop has 2 network interfaces: ethernet (eno1, 600 Metric) and wireless (wlo1, 1000 Metric) Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface ...
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cisco 4948 IGMP flooding on all ports

everyone Having trouble with multicast on cisco WS-C4948-10GE (MPC8540). I have two switches running: System image file is "bootflash:cat4000-i5k91s-mz.122-25.EWA9.bin" and System image file is "...
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running snort and IGMP v2 flooding

I am not a network guru so please bear with me. I am running snort on a PLC (running rt-linux) along with an application that needs to communicate with another instance of the same application ...
awatan's user avatar
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Is it possible to configure an IPv6 multicast address to a NIC?

Is it possible to configure an address from ff00::/8 address block to a NIC? Looks like it is not possible: # ip a add ff99::1/8 dev p2p1 RTNETLINK answers: Cannot assign requested address # # ip ...
Martin's user avatar
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routing multicast trough debian miniPC eth0->eth1

Hello i have probably noob question by i already spent some time on it and messed a local network as well so: I have miniPC for real time log purposes between network and IPTV set-top box. The box ...
J B's user avatar
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Redhat No IGMP response

I'm setting up my server to ingest a multicast. The server will initiate the request and can join the multicast for about 2:30-3:30 min. After that, it gets dropped from the multicast group due to no ...
Jamie's user avatar
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iptables translate multicast to unicast

I'm attempting to translate multicast traffic to unicast to send over the Internet. I enabled ip forwarding and tried using the following rule: iptables -t nat -A PREROUTING -i eth0 -d 239.0.0.0 -j ...
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WDS stopped working - no servers under Windows Deployment Services 2008 R2

I have three Windows 2008 R2 servers with MDT and WDS installed. It was reported multicasting stopped working on all of them. I made sure the multicast option was selected in the deployment shares' ...
Tomasz Szymon's user avatar
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Forwarding traffic - passive behavior

I spent some time trying to figuring this out. I found my core solution, but iam not satisfied, or more likely i dont fully understand the result, which buggs me. My setting: I have wall plug(port) ...
J B's user avatar
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Receive multicast frames from different subnets

I'm trying to receive on my LInux box multicast frames from hosts on a different subnet. For the experiment, and ONLY for this experiment, i have two machines connected through a network switch: ...
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Is IPv6 MLD snooping performed by Layer2 Switches over solicited-node multicast addresses?

The NDP protocol makes use of the solicited-node multicast address. A host joins its own solicited-node multicast address group both localy (netsh int ipv6 show joins) and on the layer2 domain (a ...
networkIT's user avatar
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Java Multicast Socket doesn't receive anything on Windows

I need to send and receive in multicast. I posted the question on StackOverflow Forum for checking my code: https://stackoverflow.com/questions/50131973/java-multicast-socket-doesnt-receive-anything-...
Fabio Mancuso's user avatar
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Named multicast address

Is it possible to name a multicast or broadcast address? Usually for a single machine I'd put a line in /etc/hosts. Will that work for a multicast address?
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SSH TAP tunnel & multicast groups

Is it possible to do UDP multicasting over an SSH TAP tunnel? I have set up a TAP tunnel using SSH between my Ubuntu PC and a Raspberry Pi sitting in a remote office, using this command: $ ssh -o ...
Tom's user avatar
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Is my NTP configuration working (with a multicast peer)?

Introduction I'm trying to do some work in which I must receive an NTP update from peers but I'm concerned that there isn't any being received. Here's the output of ntpq -np: remote ...
karobar's user avatar
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Windows 10 Falls Back to IGMPv2

I have a setup where I have a Linux server running an 802.11n WPA2 encrypted Wi-Fi network. There are two devices connected to this network. One is a device which generates reports and the other is a ...
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Do all ethernet switches support multicast?

I'm playing with LANs here at home and I want to support multicast. Do all switches nowadays support multicast? Even the cheap ones? I'm buying a 5-port gigabit switch. Will it support multicast?
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What routing/topology protocol(s) should be used with P2P devices with sporadic, changing connectivity?

I have several IoT devices that will sporadically come into and out of range, and connect in a partial mesh topology. For illustration purposes, imagine the interconnectivity of a Web of Trust, or ...
makerofthings7's user avatar
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What does having a network that would allow a multicast address to find host computers mean?

I'm dealing with a scenario with a service that's saying the following: "... [this service] uses multicast address 239.170.165.207 on port 49838 to find host computers, so your network must allow ...
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Arista switch - Forward multicast traffic from vlan to vlan on different switch ports with different subsets

I have an Arista DCS-7150S-24-R I got a cross connect from provider X into port #1 (port marked as vlan 100) I got a linux host connected to to the switch at port #2 (port marked as vlan 200) Ports ...
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How can I tunnel multicast traffic?

I am trying to receive multicast on 1 machine, forward it to another machine, and then replay it on that machine. test_env: the machine which has access to the original multicast stream mcast_sender: ...
Steve Lorimer's user avatar
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Change linux multicast interface

Why my multicast traffic always goes through wlan0 interface? I try ip route add 224.0.0.0/4 dev lo ip link set dev lo multicast on ip route flush cache But VLC casting to 224.0.0.1:1111 always ...
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How to disable IGMP in Raspbian

I am writing testcases for the IGMP and MLD implementation of a network switch. Those testcases run on Raspbian. However, Raspbian seems to regularly send IGMP reports/queries of its own, which ...
icehawk's user avatar
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OpenVPN and multicast routing

I have setup an OpenVPN server for remote clients to access a server that will be sending them multicast traffic, however I am unable to receive any multicast traffic. The application makes a ...
scott's user avatar
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Why multicast UDP can be slower than unicast UDP?

I have two machines (with Centos 7.3 on both) connected via 1G switch. When I measure UDP thoughput between macines with iperf it gives about 850 Mbit/s. However when I measure multicast UDP thoughput ...
Alexei Osipov's user avatar
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Multicast causes link down on Mikrotik RB2011UiAS-RM switch2

I am trying to simply push multicast traffic through the second switch of the router... for now I connected swtich 2 port 8 to my ISP router iPTV port and port9 to SagemonUHD88 IPTV decoder. I set ...
mastier's user avatar
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How to find all link local ipv6 devices on a certain interface?

We have a setup where a program on a linux server controls its linux subordinates (talks to them via TCP and UDP). There are several groups of subordinates. Each group is connected via ethernet to a ...
Adam's user avatar
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Multicast port 40000 and safetynetp

I have a vendor that is sending multicast messages using port 40000. When I watch the traffic using tcpdump the port is reporting as safetynetp as can be seen below. The application that is listening ...
Joe W's user avatar
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How can I route Multicast between segregated interfaces on Sonicwall

I realize this question might be a little too specific, and I've read all the other questions about multicast on VPN, multicast on multiple interfaces, etc. But, I've applied all the information ...
Dexter's user avatar
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OpenVPN: possible to block multicast traffic in bridged mode?

I have a bridged-mode VPN using two DD-WRT routers connected to cellular modems. To avoid excessive bandwidth usage and fees, it would be nice to block multicast traffic originating from Allen ...
Ryan Griggs's user avatar
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STP packets dropped (1 packet every 2 seconds) when irrelevant multicast group joined on the interface

I'm trying to understand weird packet drop issue when joining particular multicast group. I think this issue is related to patch introduced in kernel ver 2.6.37 Beginning with kernel 2.6.37, it has ...
pst's user avatar
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Best practices for setting up multicast destinations

I am setting up a small LAN(20ish hosts) with a many devices which output multicast traffic. I am able to select their destination IP address and port number. There are 1-10 computers on the LAN which ...
fooOnYou's user avatar
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OS X network stack ignores IGMP membership queries

We have a remote site where the Macs are not responding to IGMP membership queries, but the Windows boxes do respond. Consequently, after about 10 minutes, the IGMP-aware network switch cuts off the ...
Warren Young's user avatar
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Multicast at high speed over Wifi/AP? higher speed?

I have a small dedicated wifi network setup specifically to carry a multicast multimedia package.. no other use (no web or other data on this network, due to the arrangement). The issue I've found is ...
frank ankersly's user avatar
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multicast in private network

I'am confused about multicast in a private subnet. Currently I have the following situation: subnet 10.0.0.0/24 NAT router 10.0.0.1 (ubuntu) pc1 10.0.0.2 pc2 10.0.0.3 pc1 and pc2 using the ...
wot-stefan's user avatar
16 votes
2 answers
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Use ip route add to add multicast routes to multiple interfaces

TLDR: Is there a way to use "ip route" to add multicast routes for multiple NICs? We have software that uses two multicast groups to communicate with two different groups of devices on two separate ...
gnac's user avatar
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How to ACCEPT multicast connection with iptables's rule?

I obtain this row with iptables logging option: IN= OUT=eno49 SRC=192.168.0.72 DST=224.1.0.2 LEN=196 TOS=0x00 PREC=0x00 TTL=5 ID=53310 DF PROTO=UDP SPT=9100 DPT=8100 this packet is DROPPED I think ...
karmax's user avatar
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Is it possible to override the destination MAC of multicast frame via a static ARP entry?

I have what I believe is a somewhat obscure question. I have a very specific use case here, so please consider this question purely academic. I have a device (running Linux 2.4 kernel) which ...
Corvette1250's user avatar
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757 views

Wrong Multicast MAC address with more than one network interface

I am trying to subscribe to a multicast group from a Red Hat machine with four network interfaces, each one is on a different subnet. It only works if I bind the multicast socket on the network ...
Yorchus's user avatar
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2 votes
2 answers
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Can FOG and/ or WDS do multicast over an ordinary unmanaged Gigabit Switch? or does it need hardware with specific multicast features?

Can FOG and/ or WDS do multicast over an ordinary unmanaged Gigabit Switch? or does it need hardware with specific multicast features? Trying to help a small non profit in Asia with a poor budget. ...
ProBonoAdminVolunteerInAsia's user avatar
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UDP multicast send/receive: Routing or socat issues?

I'm using 'socat' on Linux Centos 7 to diagnose some problems. Server and clients are all linux centos7, they all have multiple interfaces. Server 10.1.1.1 is on Switch 1, 10.1.1.2 is on Switch 2. ...
surfcode's user avatar
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Office 365 Skype/Lync: Support for stream multicast or mirroring?

Does Skype for Business / Lync when used via the hosted Office 365 service have the ability to do any stream multicasting or mirroring for group meetings? Background: I’m in a branch office with a ...
Wafflecode's user avatar
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One of two machines on same network doesn't receive multicast group memberships

in remote network, we have two machines. one of them receives multicast subscriptions, another one doesn't machine one receives only igmp query: sudo tcpdump -nevv -i eth1 -s 1515 igmp tcpdump: ...
Pavel K.'s user avatar
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Hyper-V Windows hosts see/count multicast traffic that they shouldn't

I have some of my Hyper-V VM's on a network segment that pushes a lot of UDP multicast traffic (several 100MBit/s). Now, all Hyper-V Windows hosts actually see and count the traffic on the Ethernet ...
TJF's user avatar
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Is there a way to tell a machine accesible via a gre tunnel to join multicast groups via pimd or smcroute?

this has been stumping me for some time and would love any help on this. So I am subscribed to a data vendor through an intermediary firm. The intermediary firm has physical connections to the data ...
FinDev's user avatar
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Joining a UDP multicast through a server on the other side of the tunnel

I've drawn a diagram below to help with this question! So a company published a multicast UDP feed (company A) and another company connects to it (Company B). I have a point-to-point tunnel to ...
FinDev's user avatar
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how to find the number of members in a Windows IP multicast

I am able to find multicast groups by using this in Command Prompt (I found this at serverfault How do I know if IP Multicasting is enabled on my network in Windows?). netsh interface ip show joins ...
curious1's user avatar
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2 answers
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Multicasting (mDNS) for Linux Server

Background: I am running a Linux sever on a local network that acts as both a web server and a central communications server. This server communicates with multiple nodes in the system. Upon node ...
cg14's user avatar
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IP Multicast between Windows and Linux

Our team is developing linux/windows applications for our network that are talking to each other via multicast. We had it working when we only had linux boxes on the network, but we recently added a ...
dberm22's user avatar
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Cisco Nexus 7000 Multicast IGMP Snooping enabled - packets got to all interfaces

I have connected three servers to Cisco Nexus 7000 switch. Server1 send multicast packets, server2 subscribes to multicast packets and server3 is for the tests. No matter if I subscribe to multicast ...
killdaclick's user avatar