A network bridge is a network device which transparently forwards packets between two or more network segments so that they appear as one local area network (LAN).

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Good detailed explanation of /etc/network/interfaces syntax?

I understood the very basic concept of how to use /etc/network/interfaces, but all I find online are examples, example after example, which I can copy-paste from. What I miss is an explanation of the ...
23
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2answers
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Bring down and delete bridge interface that's up

How do I remove a bridge that has an IP address that was brought up manually and isn't in /etc/network/interfaces? $ ifconfig br100 br100 Link ...
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2answers
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Why does Linux require moving IP from eth interface to bridge interface

When a network interface (e.g., eth0) is added to a Linux bridge (e.g., br0), the IP address must be removed from eth0 and added to br0 for the networking to function properly. I recall reading in ...
9
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2answers
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How to know if a network interface is tap, tun, bridge or physical?

As far as i know, there are 4 main types of network interfaces in linux: tun, tap, bridge and physical. When i'm doing sys admin on machines running KVM, i usually come accross tap, bridge and ...
9
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4answers
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Docker + Bridges + DHCP

I have a lot of docker containers that I need addressable on the the same LAN as their hosts. Up until now, I have been achieving this by using setting up a bridge and manually assigning them IPs, and ...
8
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2answers
325 views

“Pipe” Wi-Fi signal through Ethernet cable

Currently the Ethernet ports in the building I work in are down, but the Wi-Fi works. I have a Wi-Fi-enabled laptop (Ubuntu 14.04 LTS (Trusty Tahr)) and a non-Wi-Fi enabled workstaion (Debian 8 (...
7
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6answers
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Cannot delete bridge - “bridge br0 is still up; can't delete it”

I have the same problem as this guy : Bring down and delete bridge interface that's up But that solution does not work for me. I remove all interfaces from the bridge using brctl delif . I then ...
7
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1answer
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Why is VirtualBox Bridged networking slow

When logged into the guest, data transfer (scp) from the host is very slow (<1MB/s). Is this expected? setup: VirtualBox host is Debian Unstable VirtualBox guest is Debian 6 (Squeeze) Bridged ...
6
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1answer
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Why IP address for Linux Bridge which is layer 2 virtual device?

Shouldn't bridge (or a switch) be working without having an IP address? I believe I can have a bridge br0 setup with eth0 and eth1 as members both having no IP addresses. I can't understand why an ...
6
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1answer
286 views

Understand Linux kernel virtual bridge port numbering

I have a Linux kernel virtual bridge which contains interfaces eth1 and tap0: # brctl show br0 bridge name bridge id STP enabled interfaces br0 8000.00016c404fa3 ...
5
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1answer
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How can I most simply transparently bridge traffic between wlan0 and eth0?

I am looking to do this on a Raspberry Pi, but I don't mind which operating system I have to install, so the easiest most out-of-the-box solution for Pidora (Fedora 20 Remix), Raspbian (Debian) or ...
5
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2answers
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How to send data from serial port over wifi?

I have microcontroller device which reads data from sensors and sends it via Serial to USB converter (ftdi232 cable). This Serial to USB converter is connected to ARMv7 mini-computer - CuBox with ...
5
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1answer
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Why does my firewall (iptables) interfere in my bridge (brctl)?

I set up a bridge br0 "attached" to two interfaces: eth0, my physical interface connected to the real LAN, vnet0, a KVM virtual interface (connected to a Windows VM). And I have this single ...
5
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1answer
2k views

tc on bridge port

I have a 4 port bridge: root@Linux-Switch:~# brctl show bridge name bridge id STP enabled interfaces br0 8000.000024cd2cb0 no eth0 eth1 ...
4
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3answers
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Using bridge utils to connect two computers via Linux

I have been using bridge utils previously to connect my network connected computers to a single interface on my Linux computer. The problem I'm having is when I installed a new Linux (with Slackware) ...
4
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2answers
59 views

How to use same interfaces settings for all wlan devices

I am working with a pcengines apu2c4 board with debian 8.4 installed.I am quite new to Linux. We use edimax ew-7811un usb wifi adapters. Obviously when you insert a wifi dongle new to the machine it ...
4
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1answer
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bridge does not forwarding packets centos

I am using CentOS 6.5 64 and use xen to create a virtual machine (CentOS) ifconfig [root@CentOS ~]# ifconfig eth0 Link encap:Ethernet HWaddr 08:00:27:54:B3:FA inet6 addr: fe80::a00:...
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1answer
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Adding wlan0 to xenbr0

I'm setting up xen on debian to do some testing and having problems with the bridge. I would like to use wlan0 as the bridge, but can't seem to get this working. Currently I have tried this: # This ...
4
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1answer
3k views

Share Internet connection from a Debian laptop to a FreeBSD desktop

I have this situation: My Debian laptop is connected to the Internet via its wlan interface through my wireless router. Recently I decided to install FreeBSD on a very old machine (a celeron 300Mhz) ...
4
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1answer
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Fedora 18 guest in VirtualBox 4.2: How to assign static IPv4 address to guest regardless of active ethernet interface on host

I have a Ubuntu 13.04 host running VirtualBox 4.2.12. This host has both a wired and a wireless network interface, but only one of which would usually be active at any given time. For example, at home ...
4
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0answers
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How to bind an lxc container to a specific bridge?

I created a specific bridge br1 and would like to bind a specific container cont1 to that bridge. I have lxc and lxd installed, if that matters (I am not sure what the difference between them really ...
4
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1answer
3k views

Bridge does not get IP via DHCP at boot

I'm running CentOS 7. I'm not running NetworkManager, and I've actually uninstalled it. My system is supposed to acquire an IPv4 address via DHCP on br0 at boot. Howver, when I log in, it has no ...
4
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1answer
3k views

Networking and Samba from a quest OS running on qemu

I'm trying to test some software on a big endian system to ensure compatibility. My plan is to use qemu on Ubuntu 12.04 to emulate a MIPS system. So far I've been able to create the quest system ...
4
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To what extent does LXC manage configuring the network interface in a container?

In the LXC config file we can specify an IP address for a container: lxc.network.type=veth lxc.network.link=br0 lxc.network.ipv4 = 10.1.0.35/16 lxc.network.flags=up lxc.network.hwaddr= 00:16:3e:24:26:...
3
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2answers
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Extra bridge interfaces get added automatically

I have a bridge set up between eth0 and br0, the bridge works fine, but sometimes, for unknown reasons and circumstances, I keep getting these off vethXXXXXX interfaces added to the bridge. When this ...
3
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1answer
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Does Linux virtual bridge support VLAN's?

Does Linux virtual bridge(configured with for example ip or brctl) support VLAN's? For example configure access ports in different VLAN's and trunk ports with only certain VLAN's enabled. Only option ...
3
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1answer
461 views

How can I bridge two interfaces with ip/iproute2?

I know how to create a bridge using brctl, but I have been advised not to use this anymore, and to use iproute2 or ip instead(since brctl is deprecated presumably). Assuming this is good advice, how ...
3
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2answers
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Do I want a Repeater or a Bridge? (OpenWrt)

I'm setting up a network with openwrt. I have a router that I have set up for wifi which I will use as an access point. I want to add another router to my network so that the two can exchange traffic ...
3
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2answers
503 views

Can I have a bridged interface without an IP?

I have 2 NICs: eth0 & eth1 on a host OS which runs some VMs (LXC) under it. The hosts eth0 is connected to a private network and configured as the primary interface. The hosts eth1 is connected ...
3
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1answer
350 views

Why do the members of a bridge lose their Ip address?

I have created a bridge using to existing network interfaces: $ brctl addif br0 eth1 $ brctl addif br0 eth2 Why do eth1 and eth2 lose their IP addresses? What's the reasoning behind it? PS this is ...
3
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2answers
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Xen, bridge and multiple IPs on CentOS

There's a new server that is assigned 5 IP addresses. I want to use Xen to run several VMs with various services. This is my first attempt to install Xen, I use this tutorial as a guideline. Stuck ...
3
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2answers
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Equivalent for netsh start network on linux

I recenty read about the Windows option for creating an access point, that will run on the same physical device, as the machine. So that I can connect my other devices to that network, and have access ...
3
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2answers
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OpenVPN bridge. Can't access machines on local network

Followed this guide: https://wiki.archlinux.org/index.php/OpenVPN_Bridge This is my setup: I have a wireless router(192.168.2.1) which connects to the Internet through a PPPoE connection and acts as ...
3
votes
1answer
81 views

Setup permanent bridge for dynamic network devices from lxc container?

TL:DR How can I make a bridge permanent (survive reboot) without adding a network device to the bridge config in /etc/network/interfaces? Hi, I just started playing around with lxc on ubuntu 14.04. ...
3
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1answer
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Settings when using a bridge

I have a bridge set up between my physical Ethernet interface, eth0, and the virtual interface for OpenVPN, tap0. The bridge has an IP address, and the machine can be contacted on that IP address from ...
3
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2answers
4k views

Bridge not working

We want to create bridge (mybridge) on our board over eth0 and eth1 interface. The board runs Linux 2.6.34.9. Following are the commands: brctl addbr mybridge ifconfig eth1 0.0.0.0 ifconfig eth0 0....
3
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1answer
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Configure public IP addresses in KVM VMs

I have a physical server running CentOS 6.5 with one interface connected to the Internet (with one public IP address). Inside this server I have two VMs created with KVM through libvirt with one ...
3
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1answer
551 views

Create virtual network adapter with own MAC and IP?

I have a server with 4 different IPs over one real NIC. Now i try to setup different virtual network adapter in debian with this IPs. The Problem is, that each IP needs also a specific MAC. Otherwise ...
3
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2answers
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no network on domU in network-bridge configuration for Xen-4.0

I created a very standard Xen-4.0 domU with network-bridge configuration. However, no packets get out from the virtual machine to the network which bridge (peth0) is attached to. From guest I can ping ...
3
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0answers
164 views

Can't connect to Virtualbox VM's static IP which is in a different subnet from the hosts's IP, but statically routed to the host HW addr

I have a physical server running Ubuntu Trusty (14.04) at a data centre where they assigned one IP address, as well as a /28 block (16 IP addresses, 14 usable) from a different subnet. They said that ...
3
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0answers
920 views

Forward multicast between two LAN segments (Chromecast)

I've found some rules but most are inconclusive. Chromecast uses DIAL and discovers via multicast from what I've understood.. I have an Ethernet-connected computer which I would like to route via my ...
3
votes
1answer
600 views

Docker error creating bridge

After installing Docker on a Ubuntu 14.04 minimal system with these commands: apt-get update apt-get install docker.io ln -sf /usr/bin/docker.io /usr/local/bin/docker sed -i '$acomplete -F _docker ...
3
votes
1answer
1k views

Arch Linux Ethernet to WiFi bridge

I want to use a Raspberry Pi running Arch Linux to extend my WiFi network. My situation is that I have a spare WiFi router that I want to use to expand my WiFi reception range as well as give me a few ...
3
votes
1answer
897 views

How to setup wireless AP with two wifi cards and ethernet as WAN on debian?

I'm trying to build wireless AP with 2 Atheros cards (AR5413 / AR5414 both), and one ethernet card to act as WAN. I am also having doubts if I should use ath5k or madwifi drivers. I've tried both ...
3
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3answers
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how do I build a bridge between two virtual machines?

I have used virt-install to create two CentOS 7 virtual machine guests on a CentOS 7 host computer. One virtual machine is called webvm, and hosts web sites on a private network. The other virtual ...
2
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2answers
476 views

Add virtual bridge without the loss of networking?

There is a dedicated server without KVM-over-IP support. The server 'owns' two IP addresses, and one of those is used for eth0 at the moment. The user needs to add a virtual bridge, in order to ...
2
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1answer
269 views

socat/netcat UDP to TCP

I am trying to bridge a connection between UDP and TCP. The UDP - must listen on port. The TCP - must connect to a server. The purpose of the connection is to control VLC player. I tried netcat and ...
2
votes
1answer
62 views

How to connect two VMs with different IP ranges to access each other?

Using KVM I have created four VMs, I have two public Ip addresses for my VMs, I know that I can assign these IPs to two of the VMs and connect them to internet by bridging my host's physical interface ...
2
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1answer
5k views

How do I set up several interfaces all bridged onto eth0?

I have found several guides to bridging a single interface (eg br0) onto eth0 but none for multiple interfaces (eg br0, br1 etc). Is this possible?
2
votes
1answer
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connecting (bridging) two networks

I would like to connect (bridge) two networks (ppp0 and eth2). Normally you would do this with brctl but one of the network-interface is a ppp-device so it won't work (ppp can't transport ppp-frames). ...