Questions tagged [dhcp]
The Dynamic Host Configuration Protocol (DHCP) is a network configuration protocol that assigns IP addresses and gateway configuration automatically.
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Routing Table Metric With Two Interfaces
I've tried for many hours now to find a solution to my issue, but I can't seem to locate a permanent explanation - I'm also an ultra noob, so forgive me if I get the basics incorrect.
I have a server ...
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20.04 Cloud-init appears to disable ipv4 DHCP on eth0
I'm doing a fresh install of 20.04 on some Raspberry Pi 3s. The SD cards were flashed with Ubuntu 20.04 Server (32bit) using the RPi imager.
When cloud init finishes wlan0 has an ipv4 address from ...
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Making initramfs using the correct host name when applying for a dhcp address?
I'm having some ubuntu servers with an encrypted root partition, and usually they do ask for the password at boot time on the console. In order to start them remotely, I'm using dropbear in the ...
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Can not connect to internet/struggling with network configuration
Trying to use Ubuntu server for a minecraft server with friends. Not had much luck. Basically when it gets to the DHCP part of the install for the network configuration, there is no IP address and the ...
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Ubuntu 22.04 vm bridge to wifi so that vms get ip address via dhcp
Preamble
I've tried following assorted tutorials. None are specific to Ubuntu 22.04. Every one I've tried so far end up with me having to reinstall to get wifi working. Some assume the machine has a ...
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Can we assign two IP addresses from different subnets to a single connection in nmtui?
I am currently using ubuntu 20.04 machine.
I have a query regarding assigning IP addressses manually to a network connection using nmtui.
Is it possible to assign two IP addresses from different ...
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Ubuntu 22.04 hotspot and Pi-hole, Issue with dnsmasq
I have an issue with the hotspot on my little server:
The hotspot is configured and I think it's ready to work, only the DHCP is missing. dnsmasq is not starting:
dnsmasq.service - dnsmasq - A ...
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Ubuntu Server 22.04 LTS using netplan and networkd on RPi4b won't assign DHCP IP to wlan0
Fresh install of Ubuntu Server 22.04 LTS on a 4GB Raspberry Pi 4b with PRO activated. On the initial boot up, I didn't realize I needed to wait until the cloud-init sequence finished so I may have ...
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network LAN ssh is running but internet can not connect
I have a old project to run an odroid cluster at home, thus I started configuring the network.
there is 5 Odroid XU4 with Ubuntu 22.04:
master with eth0 1Gbit/s 10.10.10.1 & eth1 100Mbit/s 192.168....
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What is DNS resolver associated with a network interface?
I am currently working on ubuntu 20.04 machine.
What is exactly a DNS resolver/nameserver associated with a network interface?
when i am checking the /etc/resolv.conf file, i can see nameserver 127.0....
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DNS lookup not working in a VM until I run dhclient
Have already spent 4 hours trying to debug why DNS lookups do not work when the VM boots up.
Not only did I try to debug the problem manually, but went over hundreds of articles on the internet, ...
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Recover DHCP lease if it has been lost
So my system lost it's DHCPv4 lease. Since this is the WAN uplink, the system then became unreachable. I can't see any trace that it has tried to recovery from this.
Apr 3 00:31:47 mistik systemd-...
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DHCP inet address keep disappearing
I'm having trouble with network with Ubuntu embedded on a PYNQ board. By running ifconfig I can see that the inet address keeps disappearing and then reappearing. My network interface looks like this:
...
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Unable to SSH to Ubuntu Server after changing the MTU size to 1550
The Current Setup consists of a virtual router managing the VLANS 201, 401, 601 and routing traffic between the VLANs and the external network. Device A is connected to the virtual router via a switch....
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e1000e device loses dhcp lease repatedly
I have a M70q mini PC that is using the e1000e device driver for the ethernet connection. Whenever I attempt to ftp a file to the computer, it loses its IP address. It will regain the IP address but ...
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How to block NetworkManager from changing a line from dhclient.conf when merging?
In dhclient.conf I have a line
send host-name = gethostname();
which I do not want to be changed by NM to
send host-name = '<current short host name>'
when generating the file in /var/lib/...
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Unable to resolve hostname of Ubuntu 20.04 server after adding second ip address on a second adapter - no local DNS server
I recently needed to add a second IP address to a server using a previously unused Ethernet adapter. When I did this, suddenly no workstations could resolve the hostname of that server. When I undid ...
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Discover new IP address by calling MAC address
I have two devices that is located on a remote network:
A Raspberry Pi running Ubuntu 20.04. Let us call it Alex.
Raspberry Pi Pico Wireless running my code only. Let us call it Bob.
Alex acts as a ...
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Wired Connection Not Working, Ethernet Cable Works Properly
I just performed a fresh install of Ubuntu 20.04 on my HP workstation, however the wired ethernet connection doesn't work, even though the ethernet cable works (tested on a different workstation and ...
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Ubuntu 22.04.2 - loses internet randomly/ [closed]
So I have a machine running ubuntu server 22.04.2 with a wired network connection which seems to lose internet randomly.
Running a continuous ping from the machine to google.com skips big chunks in ...
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How to configure DHCP and Static interfaces on Ubuntu 18.04.6 - Destkop
/etc/network/interfaces contains the below:
source-directory /etc/network/interfaces.d/*
auto lo
iface lo inet loopback
auto eth1
iface eth1 inet static
address 192.168.1.10
netmask 255.255....
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ISC-DHCP-Server Failover
We have recently began a project to include a Primary/Secondary ISC Failover pair. We have both servers setup and running and talking to each other.
The issue we are running into is that the lease ...
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Multipal DHCP Pool configruation in one Interface
I have an interface already configured for an internal interface, which is a static IP address in ens33. My question is How can I create multiple dhcp pools from one interface without using multiple ...
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Ubuntu server not getting DNS from DHCP Server?
My Ubuntu server doesn't seem to be getting it's DNS settings from the DHCP service on my router.
root@dios:/etc/netplan# cat 01-netcfg.yaml
network:
version: 2
renderer: networkd
...
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Set up multiple static IPs on virtual ethernet interface on Ubuntu 18.04
I'm trying to set up 5 static ipv4, 5 static ipv6s and a dhcp ipv4/6 on a single ethernet card (for unimportant reasons). I don't know if I actually need the ip addresses to have separate virtual ...
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Routing not working the same on two internal NIC
on mu Ubuntu 22.04 server I have two internal NIC and one external connected to the Internet.
I have defined the interfaces with Netplan as follows :
network:
ethernets:
eno1:
dhcp4: true
...
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Linux Wifi Hotspot - Cant start DHCP: /etc/dhcp/dhcpd.conf: interface name too long
I'm trying to setup a Wifi Hotspot on my Linux Machine. After failing to achieve it through the GUI app, linux-wifi-hotspot, I followed this guide, which was going smoothly until the last step of ...
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Bridge between physical interface and virtual (Cockpit)
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, the connection ...
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how to configure ubuntu 22.04 clients with synology dns server
I've got the latest Synology and several Ubuntu 22.04 (fully updated) but empty.
installed Synology's own DNS server: example.local
installed Synology's own DHCP server.
The client do get an IP of ...
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Unable to ping Ubuntu connected to Ethernet
I was having trouble pinging my Ubuntu host through a router so I removed the router and connecting directly via ethernet. Internet is working.
I have disabled the Ubuntu firewall. Still cant ping my ...
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DNS and/or routing broken on one machine after subnet change in LAN
I reconfigured my home router to use 192.168.39.0 as the subnet. Previously it was 192.168.0.0
I have one Ubuntu 22.04 machine which now has broken DNS and/or routing. I have eliminated hardware ...
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No automatic network connection after upgrade
I upgraded from 22.04 to 22.10. As a result of that, after each reboot the network never works by itself. I had the same issue when upgrading from 21.10 to 22.04 but somehow managed to fix it, but I ...
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Share network from eth0 to device plugged into eth1?
I have a ubuntu 20.04 server that has two ethernet ports. I am trying to set it up so eth0 is connected to my lan/internet and I have a second ethernet port (eth1) that i want to be able to plug in ...
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Ubuntu gets same IP as another device on the network
I faced with a weird issue. In our office we have wifi and after reinstalling Ubuntu 20.04 I am not able to use network due to Ubuntu gets the same ip address as another device(android) has. DHCP is ...
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VM Guest OS (homeassistant) on VLAN aware bridge does not fetch ip from dchp
I've setup VLAN aware bridges on the Host OS (Ubuntu Server 20.04 with KVM and using Netplan) and my guest OS (homeassistant OS) is not fetching the ip address from a dhcp server (external, not on ...
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Setting up secondary interface with netplan using DHCP - both interfaces in same subnet
I am trying to configure two Network interfaces on an EC2 instance using Netplan. These interfaces have the same subnet. When the cloud-init configures it, the netplan configuration looks as follows:
...
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TAP interface(l2 level) up but not sending DHCPDISCOVER packet automatically
I am creating a TAP interface instance in a VPN application at l2 level in Ubuntu 22.04. As soon as the TAP interface(example tap2) comes up, it does not send DHCPDISCOVER packet automatically. If I ...
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ISC has announced the end of life for ISC DHCP as of the end of 2022. Will ubuntu use kea DHCP instead of ISC DHCP as they suggest?
for more information about DHCP EOL:
https://www.isc.org/blogs/isc-dhcp-eol/
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Hostapd access point + isc-dhcp-server disconnects client after 2 seconds of authenticating
I have Ubuntu 22.04 with a Wi-Fi access point Hostapd + isc-dhcp-server and every time I connect a client it automatically disconnects after 2 seconds.
Here are the contents of /etc/hostapd/hostapd....
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App Armor DENIED access DHCP - profile="/{,usr/}sbin/dhclient"
I am using Ubuntu 20.04 and recently noticed that app armor has denied access to /sbin/dhclient. Which was a surprise to me since I had previous change to complain-mode, but are not in enforce-mode
/...
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Ubuntu Router Not Restoring After Network Disconnect
I am using a Ubuntu 22.04 machine as my router. I run this script at startup which sets static IP addresses, forwards packets and serves DHCP requests.
sleep 4
sudo ip addr add 192.168.0.1/24 dev ...
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UBUNTU-22.04-DHCP-failover mode issue
We have 2 DHCP servers (Ubuntu 18.04), they are configured as failover mode (primary / secondary).
They work brilliantly, no issues with them since about 4 years.
Now, we had a power cut, so one of ...
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IPv6 does not work and "no link-local IPv6 address for ens5"
When I try to ping6 ipv6.google.com I get ping6: connect: Network is unreachable. When restarting my network interface ens5 it shows a no link-local IPv6 address for ens5 message. I am pretty sure ...
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How do i make a Static ip available over a network
I'm running ubuntu server 20.04 LTS in raspi 4 model B.
I want to set a static IP in one raspi and run API over that ip and that must me accessible over the the network to which I'm connected to. I ...
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Migrate Ubuntu server from NetPlan to NetworkManager without disconnection (possibly over SSH)
I see that Ubuntu server after the installation comes as default with NetPlan with a DHCP configuration (at least in Ubuntu 22.04 focal fossa).
Some users don't want NetPlan and just want ...
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Ubuntu Server 22.04 LTS no DHCP on startup
I am wondering if there has been a regression with Ubuntu. Back when 18.04.3 came out, I noticed that my VM-based Ubuntu servers would no longer be able to get DHCP addresses from my Windows DHCP ...
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Cable LAN connection issue
I have booted Lubuntu 18.04.5 (try out mode from an USB stick, no proper installation) on an old netbook (HP Mini 210-3100) and ran into a LAN issue. First, wireless LAN access works as expected ...
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DHCP not working on 22.04 not getting gateway IP
I was using fixed IP addresses but am having to use DHCP now, and the problem is now happening that if I select the USE DHCP option for the network, I don't get the gateway IP address.
Lines starting ...
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DNS Servers stuck with ::1
I have an issue with a new install of Ubuntu 22.04 desktop.
The wifi worked well until I installed a few applications.
Everything is supposed to be configured with DHCP, however, the only DNS servers ...
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DNS names do not resolve when using a local static IP
I'm creating a Minecraft server with an old desktop computer (a HP Pavilion) running Ubuntu 22.04 and when trying to set up a local static IP, my DNS appears to stop working entirely. At first, I used ...
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