Questions tagged [bridge]
Bridging is a forwarding technique used in packet-switched computer networks. Unlike routing, bridging makes no assumptions about where in a network a particular address is located.
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How to use nft on linux bridge to block access to certain ip addr?
I have an Ubuntu box with a bridge br0 defined. The bridge has eth0 connected to the internet service and eth1 connected to the network port of a PC. The bridge is functioning as expected and passing ...
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pfSense L2 firewall not blocking half of DHCP traffic
I have a pfSense instance (NetGate SG-series), with setup:
802.11q enabled
LAN ports 1 (LANP) and 2 (LANB) with VLAN assignments
Interfaces assigned and enabled
LANP:
(1, 5t) tag configuration
...
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Linux bridge not forwarding traffic after changing bridge ports
Problem: after changing bridge-ports value of a network interface, all networking on that IP stops working. Base system is Proxmox VE 7.4, based on Debian Bullseye.
Background: I have a Proxmox VE ...
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Unable to create a Linux bridge with a VLAN interface on Fedora
I'm trying to set up a Linux bridge that includes a VLAN interface on my Fedora system. My goal is to use this bridge with virt-manager to create multiple VMs, each with an interface in the bridge ...
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Libvirt - UDP not working between host and VM
Host: 192.168.1.144/24
VMs(routed) network: 192.168.122.0/24
I have VMs connected to libvirt's routed network.
<network>
<name>routed-122</name>
<uuid>86ca64a6-7fea-4cf8-...
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Public IP on KVM VMs and DNS setup on host machine
I'm using KVM to create two VMs for hosting NMS servers for the company's devices. I want to manually assign a public ip to both VMs and the host machine (Ubuntu 22.04 desktop [although I mostly use ...
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How does GRE interface route packet to remote endpoint
I have the following topology which I configured to run a GRE tunnel between my Desktop and the wireless router.
On the PC:
ip link add l2gre0 type gretap remote 192.168.0.103 local 192.168.0.10
On ...
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Is it possible to bypass linux bridge device and assign linux vlan directly to bridge member on proxmox (Debian)?
I came up with the following situation. We have a Proxmox node with a 40gb Mellanox QSFP+ card connected to switch. The 40gb interface is added as a slave to vlan aware linux bridge. To that bridge ...
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I cannot see my OpenVPN TAP adapters in Hyper-V external switch bridging
I cannot see my OpenVPN TAP adapters in Hyper-V external switch bridging. Is it even supported in Hyper-V? I do not see any documentation where it says it is either supported or not. I have Windows 11 ...
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OpenVPN assign client same ip address as static address on router network
I have an OpenVPN server running on a machine behind my home router, and two clients, one Macbook and one iPhone.
When I'm not using OpenVPN, I can statically assign IP addresses to the Macbook and ...
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Proxmox VE Dedicated Server OVH - Config Issues In Network Setup With 1 Public IP
Problem: (No Internet & No DHCP)
I cannot seem to get my VM's to connect to the internet nor am I able to setup a DHCP server to automatically assign IPs to them.
Introduction/PSA for dupes: I've ...
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No layer 2 traffic in an Open vSwitch bridge
I see no traffic in layer 2 and above in an OVS bridge, but I do see layer 1 traffic.
I have the following setup:
I have created a Linux VirtualBox VM with three adapters: NAT with port forwarding the ...
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proxmox / ovh ip failover and bridge
I have installed both Lubuntu Desktop and Ubuntu Server on Proxmox VMs. However, I don't have internet access on either of them.
I followed this tutorial, but I still don't have internet access: https:...
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Bridged mode does not present network address, but instead 10.0.2.15/24
Host OS: Windows 11
Guest: GNU/Linux Debian 11
Versión VirtualBox: Versión 7.0.6 r155176 (Qt5.15.2)
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nftables: getting a per-port whitelist to work
Setup: Ubuntu 20.04, created a bridge "br0" with brctl, added three physical ports to it: enp10s0, enp7s0 and enp5s0.
The desire: enp5s0 and enp7s0 should be able to talk to each other on ...
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Strange issue with bridges on Ubuntu server and libvirt; looks like MAC address conflict
We have been using bridges and libvirt VMs for a long time (starting with Ubuntu 16.04). Recently, we have encountered a problem with bridges (on VLAns). We have not yet identified what conditions ...
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OpenVPN bridging with server and multiple clients?
I am setting up a bridge that will connect two or more disjoint physical networks in the single shared "ethernet space" (e.g. I want everything to work like it is plugged into one Ethernet ...
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Bridge Becomes Unresponsive (must reboot)
We noticed in some of our hardware that our switch (an integrated KSZ9477) stops responding, with the logs showing the following:
[ 9585.977985] ksz9477-switch 0-005f port1: Link is Down
[ 9585.983206]...
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how to filter bridge interface packets with single iptables rule?
I want to filter br1 interface in/out packets that have a specific tcp port number.
Given a setup with eth0 and eth1 in a bridge br1:
| |
eth0 eth1
| == br1== | ...
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vm machines cannot ping each other via bridge network [duplicate]
I created vhost1 and vhost2 by using virt-manager which run on a Ubuntu server 22.04
The Host and VMS connected via a bridge network. So here's the thing:
The ping working fine between Host and VMS, ...
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Linux bridge does not propagate multicast ntp messages
My hardware, based on imx8, has two ethernet interfaces. These are connected together as a bridge, all messages not for this he are forwarded. Everything works as expected except multicast messages: ...
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What is causing large TCP messages to have low throughput in one direction when using ethernet-to-wifi bridge?
I have two computers, Orin and NUC, which are connected via ethernet cable directly.
NUC is connected to a router with internet via WiFi (for completeness, not relevant to problem, I hope), and is ...
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Bridge between networks
I'm beginner and I'm trying to set bridge between two networks in Virtual Box. I've created two VMs (Debian1 and Debian2) and for network settings I set Debian1 to intnet1(Internal network) and ...
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Bridge not reaching internal network for OpenVPN Ethernet Bridge in a Ubuntu 22.04 VM on ESXi
I want to set up OpenVPN Ethernet Bridging. I'm following the steps from https://openvpn.net/community-resources/ethernet-bridging/ and after setting configuring the bridge as described in https://...
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Occasional packet loss between bridge interfaces
I have two virtualization servers based on libvirt and KVM. And sometimes I see packages get lost on one particular virtual machine. After restarting the virtualization host this problem is solved, ...
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Bridge between physical interface and virtual (Cockpit)
Good afternoon.
At the moment I'm using Debian 11 as the main system and Ubuntu 18.04 as the system for virtualization, I do all the management through Cockpit.
The server is connected via a router, ...
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Lower throughput in a Bridge created as a Ethernet Switch in a Ubuntu Server -
The setup is given below. I have a server with NIC(eth0 and eth1). I have created a bridge br0. The idea is I want to send the packets received from eth0 via br0 to eth1.
(Laptop)__________Ubuntu ...
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Linux: STP does not converge among linux containers
I'm trying to create a lab in GNS3 with docker containers to understand more about spanning-tree. My lab is very simple: there are two Linux/Alpine containers with two links connecting them:
-------- ...
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Physical/Bridge and KVM ports shows up even after unplugged the cable!
We have Debian 10, it has two physical interfaces which we bridge to KVM.
The issue I have is, when I shutdown the port from my virtual operating system or I disconnect the cable the birdge and ...
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Linux virtual machine network DDOS protection
I have dedicated server with installed virsh. On the server I have 5 virtual servers.
When someone DDOS attack dedicated server is everyting ok. I hardly know it's an attack.
But if someone attacks ...
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migrating openBSD VM from linux host to linux host messes up name resolution
I created an OpenBSD guest VM on fedora. I migrated the qcow2 image from fedora to rockylinux and used it create a new VM.
virt-install \
--import \
--virt-type=kvm \
--name=...
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Can I measure the performance of a linux software bridge using this setup?
I need to measure the performance of a linux network bridge (https://wiki.archlinux.org/title/Network_bridge) on a particular machine (machine A). My initial idea for a setup looked like this:
...
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Access bridge Network from Router's Network and vice versa
My ISP provided an ONT cum wireless router device that connects to internet via PPPoE.
However I decided to use the provided device just as a modem and bridge it to a high speed wireless router ...
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Bridge interface causes high CPU utilization
We are facing a weird issue with a server we have on our laboratory. Specifically, the server shows high CPU utilization from low priority processes (blue color in htop) with 50% of the cores ...
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Ubuntu ethernet bridge limited to 1Gbs?
I have an Intel 522SFP network adapter in a Ubuntu Server machine and I am facing a strange issue with speed.
If I use it "directly" with this netplan (enp1s0f0 interface) :
# This is the ...
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IPV6 conflict VM Ubuntu 20.04 - Netplan
I have a problem, I've two virtual machines, but the problem is that when I turn on the second VM I lost the connection on the first one and vice versa.
Here is the bridge netplan configuration on the ...
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rhel 9, firewalld(nftables backend), libvirt and custom bridges, masquerading not working
I have a remote server with one network interface, which has a public IP address (enp5s0).
I've created an isolated network as follows:
<network>
<name>LAN-bridge</name>
<uuid&...
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untagged traffic must become tagged traffic after passing through the bridge
I'm trying to achieve something simple.
I have a machine which has a single physical port enp89s0. this is connected to the native VLAN (VLAN=1).
I need to create VMs and place them on a separate VLAN=...
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linux bridge vlan-aware and untagged traffic
I have the following use case. A machine which runs VMs that have to be located to a VLAN with ID 166. The traffic must go out of an physical interface enp89s0 which is connected to the primary ...
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Debian 11 network bridging issue
Was hoping someone might be able to help with a bridging issue on Debian 11... I can't get it to work and I've been tearing my hair out all day! The bridged interface will not get an IP via DHCP and ...
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Debian 11 - Cockpit VMs - Host and VM cannot ping each other
I have a server running Debian 11. I installed Docker and have several containers running successfully. I also like the option of being able to spin up libvirt/qEMU VMs via Cockpit. (FWIW, I also have ...
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KVM and Docker Containers on same Host to receive IP from DHCP (via bridge)
I've got a real host, headless and Debian as OS. On this host I've got a few KVM machines and a few Docker Containers.
The KVM machines receive their IP from a PI-Hole DHCP in my network. Now I ...
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libvirt with qemu guest, bridged networking does not work
I am trying to get a VM operational and working so my router can forward a high port to its SSH, allowing someone on the Internet to connect to the VM. I am familiar with how to make that part of it ...
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Two completely independent bridges on one ethernet card, possible?
Docker creates its own bridge, and when there is an existing bridge, it seems that the two collide. I have personally experienced that and multiple sources on the Internet mention about that problem. ...
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How to connect veth interfaces to bridge slave ports
This will probably be easier to explain with a diagram, so this is the basic setup:
There are 2 containers 10.0.0.1 & 10.0.0.2 running inside a host machine, and I've also created a linux bridge ...
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Bridging firewall between two sites with same network
We have been assigned an IP-network for a test lab we can use for our equipment. To make sure our mistakes wont leave us nor anything from the outside will disturb us we want to setup a firewall ...
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Network Solution to allow LAN to communicate to a different SubNet via a Ubuntu BOX
EDIT: I have added a topology diagram to make it clearer.
I want to access the subnet 172.19.X.X (BLUE) from LAN->M2
I am already able to do via M1 which has a static route.
I trying to solve a ...
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Linux: Why is ARP not answered via VLAN Bridge
Our Goal
We want to run a server with several QEMU VMs, some of the VMs should be connected to separate VLANs. The host is connected to a switch via bonding and should have a VLAN-aware bridge where ...
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Docker container loses Internet access after setting Docker to use manually created bridge
I need a bridge network for QEMU/KVM virtual machines. But then, if I just install Docker, virtual machines lose Internet access. The solution I have found was making Docker use that existing bridge ...
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740
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Libvirt routing between two NAT networks
I have following two networks,
<network>
<name>subsys-network</name>
<bridge name="virbr1"/>
<forward mode="nat"/>
<ip address="192....
