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Questions tagged [bridge]

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 syntax, an explanation of the meaning of the…
Foo Bar
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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 encap:Ethernet HWaddr 00:00:00:00:00:00 …
Lorin Hochstein
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Why assign MAC and IP addresses on Bridge interface

Say I create a bridge interface on linux (br0) and add to it some interfaces (eth0, tap0, etc.). My understanding is that this interface act like a virtual switch with all its interfaces/ports that I add to it. What is the meaning of assigning a MAC…
Gradient
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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 do I create a bridge using ip? For instance, say I…
Totem
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Create wireless access point and share internet connection with nmcli

How can I create a Wi-Fi hotspot with the command line tool nmcli and share/bridge the ethernet internet connection with the wireless access point? Furthermore, how can I start this automatically at boot? Is this possible with nmcli?
BuZZ-dEE
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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 some Open vSwitch readme file (which I can't find…
Lorin Hochstein
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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 across tap, bridge and physical interfaces on the same machine, without being…
user368507
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How do I configure a network interface bridge from WiFi to Ethernet with Debian?

I am using Raspberry Pi using Raspbian which is just Debian. I would like to bridge from the primary WiFi network router that connects to Cox Cable to my cabled router here for my subnet to have reliable internet access. It needs to be a…
SDsolar
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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 set the link to down using either ifconfig or ip. I…
LinusK
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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 interface each. I want to assign one public IP address…
logoff
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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 managing the IPs myself. An example startup…
Programster
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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 address should be allocated to br0?
Vinay Kumar
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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 firewall rule in the forward chain: iptables -A…
Totor
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Bridged interfaces and VLAN tags

I'm trying to set up a system that joins an untagged Ethernet network to a TAP tunnel, adding a VLAN tag as the traffic moves to the tunnel. So far I have: eth0 - the physical Ethernet interface carrying untagged traffic. tap1 - the TAP tunnel…
Tom
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What is virtual bridge with -nic in the end of name

When I use KVM, I create a virtual bridge called virbr0, there is also a bridge called virbr0-nic. Even after I disable and delete virbr0, the virbr0-nic is still there. Can anyone explain to me what is this? Thank you.
thenewasker
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