Questions tagged [dhcp]
The Dynamic Host Configuration Protocol (DHCP) is a network configuration protocol that assigns IP addresses and gateway configuration automatically.
1,072 questions
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DHCP Issue with Ubuntu 24.04? Suspect wrong behavior with DHCPNAK
We have the problem that Ubuntu clients cannot obtain an IP address from our DHCP Server (Cisco Router).
As I understand, the problem is that the client does a DHCPREQUEST with its previous IP address ...
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dynamic IP keeps coming back
We've got a ghost IP address that keeps coming back. 10.203.32.245 has type dynamic but dhcpd is not running, I cant find anything on the machine dhcp although I dont know much about dhcp.
After ...
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Get DHCP Gateway networkd-dispatcher
For Ubuntu 24.04 Server, is there a way to get the DHCP gateway in a networkd-dispatcher script when the DHCP interface comes up/is renewed (like $new_router in a dhclient hook script).
Update after ...
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Where to Place Scripts that Are Executed on Network Change in 24.04 Server
Where is the place to put scripts that need to be executed on changes to the network for Ubuntu 24.04 server? For example, when DHCP is renewed or connected, I need to reconfigure routing for a ...
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Upgrade 22.04 -> 24.04.01 fails - no network after rollback
I am attempting to upgrade from 22.04 to 24.04(.01) for months (sporadically tried 2-3 times in September, once mid October and once yesterday) and still the same issue happens: the upgrade tool ...
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Why does enp5s0 show a static AND dynamic ipv4 address when I have set dhcp4 to no in netplan yaml file?
I am using Ubuntu 24.04. I have networkd as the renderer, with Network Manager disabled.
I have a few NUCs all using networkd and all with enp5s0 dhcp4 set to no.
One of the NUCs (only 1 so far, I ...
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Connect to both Ethernet and WiFi at the same time without DHCP
I have a local server which connects to two routers via ethernet (ip a 192.x.x.x) and wifi (ip a 10.x.x.x). The ethernet router (connected to the internet) only provides internet to the server and not ...
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DHCPv4 address doesn't load on Ubuntu Server setup
So, in the the installer for Ubuntu Server (I tried both 22 and 24) I cannot seem to get a IPv4 address at all. In the "Network Configuration" step, I have selected DHCP as the IPv4 method. ...
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I have a fresh Ubuntu 24.04 desktop with DHCP and it adds another nameserver to its network config
I've just started using Ubuntu on my laptop. After setting up I couldn't connect to my server via SSH. After some digging I found out the DHCP client on my laptop and server (both running Ubuntu 24.04)...
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Script to update samba dns not working when executed from isc-dhcp server (while works fine when I become the exact same user)
I am going nuts here. Running ubuntu 24.0, which is hosting my samba active directory server, and isc-dhcp server.
I can call samba-tool to add DNS records from any user on my server.
$ samba-tool dns ...
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Trying to setup dhcp-dyndns with samba ad - RPC fails
I want to get dhcp-dyndns working on my samba server (running on ubuntu 24.04) but I am stuck on the following:
sudo samba-tool dns add server spatiebas.net hp-ubuntu A 192.168.2.163 --use-kerberos=...
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wireless AP using netplan on 24.04 -- how to disable dnsmasq (automatic dhcp/dns)
I am trying to setup Wifi AP using netplan.
My configuration is as follows
network:
version: 2
renderer: NetworkManager
ethernets:
enP3p49s0:
mtu: 9000
enP4p65s0:
mtu: 9000
...
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My new Ubuntu Install isnt working properly
I just installed Ubuntu Server on my old laptop in hope of creating a home server, but ive noticed multiple commands that worked natively on other machines didnt work on this one, requiring and apt ...
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How to configure multipass istance so that it can connect to router/gateway on the host subnet?
I'm newbie to multipass.
I've succesfully created an Ubuntu 24.04 LTS instance using:
multipass launch --name test
I've noted that the instance acquire an IP address on a subnet like 172.16.xxx.xxx
...
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Temporary failure in name resolution on new Ubuntu Server setup
strong textI am not very experienced, but I am trying to run Ubuntu Server on an old laptop for practice as I am studying to work in a data center and want more familiarity working with linux. I have ...
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Server 24.04 only starts a single interface on boot
ubuntu 24.04
I had the system working as intended with just a single eth0 ethernet interface
I enabled wifi on the system, now on boot wlan0 gets a DHCP address, while eth0 just sits idle.
user@...
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How to make network settings permanent?
I have Ubuntu 24.04 and a local network. I try to configure in the Network settings a wired connection with manual IPv4 mode, static IP address, I apply it and it works, but after a while it is still ...
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Why is IPv4 not working on Ubuntu 22.04 with new router/network
I am trying to connect to a new router using my Ubuntu 22.04 laptop.
It connects just fine, however I am having troubles getting IPV4 to work.
If I go to https://www.whatismyip.com/, most of the time ...
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DHCP takes forever - Imaginary ACD conflict
For the past year, I've had increasing difficulty to connect to my work's network. Wifi is disabled, I get an IPv6 immediately, but it takes between 1 and 30min to obtain an IPv4 address. Unplug/...
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Difficulty in connecting TP Link Wifi Extender with Ubuntu 24.04
I have 3 TP Link Wifi extenders (2 different models) and can not connect to any of them in Automatic mode in Ubuntu 24.04. Connecting directly to my hub works OK. Manual configuration of IP addresses ...
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Cannot resolve own local (avahi) hostname
After swapping a faulty router, trying to ssh from PC "A" (Ubuntu 20.04.6) to PC "A", produces the error message: ssh: Could not resolve hostname pca.local: Name or service not ...
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How to modify sbin.dhclient apparmor profile which is preventing automatic DHCP connection to network after upgrade to Ubuntu 24.04
After upgrading to Ubuntu 24.04 I can't make any network connections, wired or wireless with automatic DHCP enabled.
I have traced the problem to apparmor which is giving the following error messages ...
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WiFi not connecting after upgrade to Ubuntu 24.04. Problem with apparmor?
After upgrading to Ubuntu 24.04 I can't make any network connections, wired or wireless with automatic DHCP enabled. If I set IP Address, Netmask and Gateway manually everything works. To get the ...
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noble 24.04 ssh after DHCP reservation
When I installed 24.04 on my two machines (let's call them foo1 and foo2), Ubuntu settings has an ssh feature in settings|system|secure shell which would allow me to simply type ssh foo2 from foo1 to ...
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Netplan with source-based routing for multiple NICs and Gateways
I want to configure an Ubuntu VM with multiple NICs and Gateways:
ens18: 192.168.10.0/24
ens19: 192.168.20.0/24
ens20: 192.168.30.0/24
In the best case, the IPs should be provided by my DHCP server.
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Route between two network interfaces (one with VPN, the other one served DHCP addresses)
I tried to find an answer to my question, but I've not found anything...If this has been asked and answered I'll be happy with a pointer.
I have a server running Ubuntu 23.10 with two network ...
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How can i bridge eth interfaces with no bridge (let me explain)
I have a device that has 3 ETH interfaces.
This way I installed the Ubuntu server on it to use the Pi-Hole application
I want to use my ETH0 to receive the Wan cable from my internet provider moden ...
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Dual nic server with open client http port unreachable
I am setting up a poe switch connected to my ubuntu server 20.04. I am running an amd 5700 with some generic parts in a minipc that is being used as an nvr. I have a internet facing nic, eno1, where ...
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failing pxeboot install for 24.04 Server LTS
I'm trying to set up a pxeboot installer for 24.04 Server LTS. The machine finds our PXE and TFTP just fine, and loads the kernel and initrd. But when it gets to the install, it fails to recognize ...
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DHCP does not work
I'm trying to config a notebook as router, with 3 NICs, 2 used to connect to internet (with modems with DHCP servers embeded), and 1 to connect to LAN, with a switch (I want to use an ubuntu dhcp ...
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ip-config-unavailable DHCP error from NetworkManager
Overview and Environment
I recently set up a new VirtualBox VM and ran into some strange network behavior. The machine is running Ubuntu 22.04 and after installing the virtualbox guest additions, my I ...
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When does ubuntu initiate a DHCP lease renewal?
After doing some research. I found out that some DHCP clients initiate a lease renew when 50% of the lease time has elapsed. And I need to know if this is valid for ubuntu 20 and later DHCP clients. I ...
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ISC-DHCP-Server Crash without any error messages
I have two server machines with ubuntu 22.04 LTS. One is the master, the secondary is standby.
Both server serve NTP service, Bind9 services and DHCP services (bind9 & DHCP additionally providing ...
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Ubuntu 20 desktop has my external IP
I have a small factor PC connecting to LAN1 port of a router that acts as a wifi bridge to other parts of my network. The traffic eventually leaves the house from a Bell Canada router. Yesterday I ...
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dnsmasq configuration for TFTP + ProxyDHCP in Ubuntu Server 22.04.3 LTS
I'm trying to configure a PXE setup, in which my Ubuntu Server 22.04.3 LTS would act as TFTP server + ProxyDHCP (current DHCP server has to remain untouched). I've googled a lot, and tried a lot of ...
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Ubuntu Server with 2 nics
I would lik to pose a question here because i'm missing something with the settings on a ubuntu server 22.04 with 2 nics. I think it should be fairly easy because with other servers (NethServer ...
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DHCPD and Appamor
I running ubuntu 22.04 on raspberry pi, with fixed IPv4 address. On the server a isc-dhcp-server is running. (i know isc-dhcp-server is outdated an not in service anymore).
While starting appamor ...
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Impossible to make IP static - SOLVED
I may be had an upgrade problem from Ubuntu 20.04 to 22.04 that I can't solve.
My IP was before static at 192.168.0.100 on the "ens1" interface, but the interface have been set to "...
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netplan config is ignored, who reconfigures my network?
I have a machine with multiple NIC, for the sake of simplicity we call them
ext0: uses DHCP, goes to the outside
int0 and int1: have static IP adresses, go to some private network, where there is ...
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kea-dhcp-server logs vs isc-dhcp-server logs
So switching from isc to kea dhcp server I can't seem to find "device name" (in this example, Chromecast-Ultra) in the log anymore.
I.e. with the isc dhcp server I would get:
Jun 2 23:45:...
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Ubuntu 22.04 is connected to internet, but cannot open any website in the browser
HELP!!!
everything was ok until I went to the office and connected my laptop to the Wi-Fi.
then I came home and everything was destroyed!
My Ubuntu is connected to wifi, and the ping of 8.8.8.8 is ok, ...
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So I am trying to install isc-dhcp-server, but when I tried installing it, the following errors show
sudo apt-get install isc-dhcp-server
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
Some packages could not be installed. This may mean that you have ...
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Ubuntu DHCP client uses IDs instead of MAC addresses. Can't change this behavior
I'm trying to use DHCP static lease assignment instead of manually managing static IPs for some of our servers. However Ubuntu switched from MAC addresses to some DHCP IDs becoming useless after major ...
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Single Network Interface Deferent IP address and Gateway for Home and Office Networks
I need to connect my laptop running Ubuntu Server 22.04 to my home network 192.168.0.0/24 and Office network 192.168.1.0/24 without manually changing the settings every time. Is this possible with ...
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"failure to parse lease: could not get netmask from lease" when connecting to an AP generated by hostapd
I have a Linux device running that generates an access point using hostapd and udhcpd (I followed this guide). I used to connect to it with my Ubuntu 16 PC, but after the update to Ubuntu 22 I can't ...
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netplan with vlan dhcp does not assign address
I have a device with two physical network interfaces, enp2s0 and enp3s0!
All communication should be assigt to vlans.
The device runs ubuntu and is a host for a KVM system, therefor also a bridge is ...
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MacVTap in KVM not getting IP address from Local Network DHCP
Trying to create a KVM with MacVTap interface, but there is no ip assigned to it
Referring to these docs to create the kvm.
Followed the creation of network properly, i.e added interface in the ...
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Netplan Configuration Isssue: Unable to obtain ip address for ethernet configured with dhcp4
Goal:
Determine why configuring an interface with only dhcp4 fails.
Setup
I am working on configuring netplan for a Virtualbox VM.
The VM has 1 bridged adapter connected to my machines wlo1 and 2 ...
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How to get a static internal IP for Ubuntu server? [closed]
I'm trying to get my home server to use a static IP instead of the one from the DHCP.
I'm using Ubuntu server 22.04.
I replaced the file /etc/netplan/00-installer-config.yml with a file named /etc/...
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Static routes configured in Netplan bouncing DHCP lease files
I configure static routes on a DHCP interface using Netplan on Ubuntu 20.04 as followings:
network:
ethernets:
ens4:
dhcp4: true
routes:
- to: 10.1.1....
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