Questions tagged [dhcp]

DHCP stands for Dynamic Host Configuration Protocol and is an auto configuration protocol used on IP networks and an extension of the Bootstrap Protocol.

Filter by
Sorted by
Tagged with
1 vote
1 answer
963 views

dnsmasq DHCP server not responding

I have connected a HikVision camera to a raspberry pi through two ethernet power line adapters TP-Link TL-PA4010. I have configured the eth0 interface of the raspberry to have a static ip address. In /...
Luke Skywalker's user avatar
1 vote
1 answer
223 views

Applying initcwn/ initrwnd to routes from DHCP

I am using Amazon Linux 2023 (which is based on Fedora and uses systemd-networkd for DHCP). ip route show shows routes like default via 10.0.0.1 dev enX0 proto dhcp src 10.0.0.211 metric 1024 I would ...
Bobby Impollonia's user avatar
0 votes
0 answers
332 views

Azure DHCP Options

It appears that Azure doesn't provide many DHCP options for new VMs. On a new client, I looked at the registry entry HKLM/System/ControlSet001/Services/TCPIP/Parameters/Interfaces and found only these ...
Michael Cornn's user avatar
0 votes
0 answers
500 views

Reserve IP based on DHCP Option 61 insted of MAC Address

a DHCP client is sending a discovery packet with option 61. Now the Windows server 2019 /2022 needs to respond with the offer based on the DHCP reservation, reservation is registered based on option ...
Abel K.Bil's user avatar
-1 votes
1 answer
1k views

How does vSphere DHCP assign IP addresses?

I have installed Ubuntu in a vSphere VM and due to some error, it got the wrong IP address. I asked IT to fix the DHCP entry and they did but the VM kept getting assigned the wrong IP. I could get it ...
gdkrmr's user avatar
  • 103
1 vote
1 answer
406 views

DHCP server does not provide correct filename for PXE

I'm trying to configure PXE server for both Legacy/UEFI support. So I need to provide different bootloaders based on architecture of machine. Here's part of dhcpd.conf: option architecture-type code ...
SibVal's user avatar
  • 11
0 votes
0 answers
220 views

DHCP Renew vs rebind timers

Windows DHCP, FortiGate relay. No rule that allows for direct renew from PC -> DHCP serwer that gave the IP. 20 minutes expiration timer, 10 for renew, 17.30 for rebind. What happens: After 10 ...
MSWork's user avatar
  • 1
0 votes
1 answer
41 views

Windows DHCP IOT retain same IP

I am trying to address a problem. We have a windows DHCP server and some devices, which we need to replace on needs. The device has a custom DHCP client which sends DHCP-DISCOVERY Packet with ...
Abel K.Bil's user avatar
1 vote
0 answers
501 views

Manage UniFi DHCP reservations on UDM via shell

I'd like to be able to manage DHCP reservations on my Ubiquiti Dream Machine (UDM) directly via shell (scripting or Ansible would also be acceptable). I've tried to locate dhcpd or dnsmasq ...
Sam Erde's user avatar
  • 3,467
1 vote
1 answer
373 views

Forcing static IP on libvirt

I've seen this question and others online, yet my problem persists. I have a gentoo host with the following interface: virbr0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet ...
vesperto's user avatar
  • 200
1 vote
2 answers
614 views

How do you get docker to work in amazon vpc? (ip assignment coordination)

Is there a way to block out a range of ips in the VPC? Alternatively is there a way to get docker (docker compose) to use dhcp to get ip addresses? If it does so will they be blocked from being ...
Roman A. Taycher's user avatar
0 votes
0 answers
807 views

dnsmasq not resolving hosts properly

Using DD-WRT, dnsmasq seems to be failing to correctly resolve hosts, and I can not understand why. root@gcs:~# cat /etc/resolv.conf nameserver 192.168.1.1 root@gcs:~# cat /tmp/dnsmasq.conf ... dhcp-...
Matt Clark's user avatar
0 votes
1 answer
852 views

Same FQDN for different IP depending on connection

I run a Kerberos / LDAP user authentication on Debian, which works nicely for decades. I now would like to use notebooks, which may connect by wire or by WiFi. I'm stuck thinking how to set up this ...
Lars Hanke's user avatar
1 vote
0 answers
281 views

How to configure dnsmasq per interface nameservers from DHCP leases

I am working on an IoT device that has three network interfaces: Ethernet, WiFi, and LTE. The interfaces provide redundancy and fail-over for network connectivity, and any combination of the ...
timothy.godfrey's user avatar
1 vote
2 answers
2k views

PXE with proxyDHCP server: What makes a DHCP client accept / ignore offers from primary DHCP?

I am considering a setup with a primary DHCP server providing "IP data" (IP address, subnet mask, DNS, …), and a proxyDHCP server providing only PXE boot options. As it happens, my proxyDHCP ...
rikinet's user avatar
  • 33
0 votes
1 answer
135 views

Migration strategy to migrate a DHCP scope from old DHCP server to new DHCP server as smooth as possible

My current homeLab and entire home is currently running on a single subnet 192.168.0.0/24 with my ISP provided router running a DHCP scope handing out addresses in the 192.168.0.20-192.168.0.254 range,...
Simon Kepp Nielsen 's user avatar
3 votes
1 answer
1k views

How to set kvm to use router's dhcp in linux?

I'm new to kvm and my question may be obvious to some. How to use the local router dhcp instead the kvm local dhcp. The local dhcp has a range starting from 192.168.122.1 and i need it to use the ...
Joao Henrique da Silva's user avatar
1 vote
1 answer
262 views

Can DHCP Option121 work with DHCP Option3 together?

I have a router with DHCP Option3(Router) set, and it works well. My Ubuntu22.04 machine was able to configure the default route automatically. Yesterday, I configured DHCP Option121 (Classless ...
Shiyao Wang's user avatar
1 vote
1 answer
2k views

temporarily set eth0 to dhcp linux

My ip address on a beaglebone is set to: $ ip address show dev eth0 4: eth0: <BROADCAST,MULTICAST,DYNAMIC,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000 link/ether 64:33:db:...
Jonathan Leslie's user avatar
2 votes
0 answers
210 views

NTP Server Precedence using systemd-timesyncd

I'm looking for documentation which specifies the precedence / priority of NTP servers (ubuntu 20.04). I am using timesyncd which has the ntp.ubuntu server But when connecting to the network via DHCP ...
Jake Baker's user avatar
-1 votes
1 answer
456 views

computer get dhcp from windows server dhcp server that is in other subnet

i have server with windows server 2019 with dhcp server role installed i'v created this scope: 192.168.9.1 - 192.168.9.10 with subnet 255.255.0.0 also i'v created a virtual lan card with this ip: 192....
mikuzan's user avatar
  • 11
0 votes
1 answer
59 views

Force sending DHCP options

I have a lab spectrometer that boots using PXE from boot files stored on a computer. They exist inside a local network with the computer acting as both the DHCP and TFTP server. The spectrometer ...
HKaras's user avatar
  • 1
0 votes
1 answer
317 views

Setting up LAN gateway for school club network - "No subnet declaration for enp3s0"

I am a computing teacher, I am trying to setup a "sandbox" network with internet access for an after school computing club. I have an old PC (Debian 11 installation) with 2 ethernet ...
ICT Teacher's user avatar
0 votes
0 answers
528 views

DHCP Discover Packets don't reach server

I have a dumb IoT device that simply asks for a DHCP lease and gets no answer. I figured out that the request never reaches my routers DHCP server and I have no clue on why that happens. If I run a ...
Hokascha's user avatar
  • 139
-1 votes
1 answer
226 views

Is there a way to have Windows active directory give a different ip address?

Here is a summary of my problem. I have configured a switch with DHCP capabilities and have connected my machine running Windows Server 2019 to the switch and received an IP from the scope perfectly. ...
Alexis's user avatar
  • 1
0 votes
1 answer
664 views

Difference between ifup and dhclient - different result?

On Debian 10 (buster), I configured the DHCP with the MAC address but it does not work. When i use "ifup" command, the result is wrong. I need to configure this IP: 192.168.251.11 but DHCP ...
BeWog's user avatar
  • 11
0 votes
0 answers
86 views

Configure a DHCP server with isc that gives the clients IPs depending on the OS

The problem is that I cannot put a static IP or filter by mac because some clients have dual boot and use both Windows and Ubuntu, I need to be able to somehow distinguish between both OS and both ...
vicentG's user avatar
0 votes
0 answers
632 views

Deleting all dynamic DNS records from AD-Integrated DNS server? What can go wrong?

[1 Forest, 1 Domain, 2 DCs and nothing more - nothing special] Is it OK, to remove all dynamic records from DNS. If I decide to do so, should I do the same on the second Domain Controller? Beside one ...
v.doro2's user avatar
1 vote
0 answers
767 views

dhcpcd keeps giving me a deprecated IPv6 address form my ISP

My ISP (EPB in Tennessee) recently rolled out IPv6. I had my router setup for IPv6 from a previous ISP, so it worked immediately at first. But then, dnsmasq stopped sending out router advertisements, ...
djsumdog's user avatar
  • 1,120
0 votes
1 answer
815 views

Unable to access server using ssh after setting a static ip in alpine Linux

I am trying to configure a new Alpine server, and I have some basic knowledge of networking & Linux only. Everything works seamlessly if I use the default configs with DHCP, but breaks when I try ...
Samdeesh's user avatar
  • 101
0 votes
1 answer
1k views

how to know device IP is static or dhcp on linux dhcp server [closed]

My system is Linux. I use udhcpd tool to build a dhcp server. I want to know what method(static or dhcp) is used for connected device on my linux server How can I do? do have any cmd can reach this ...
Niu Ar's user avatar
  • 21
1 vote
1 answer
347 views

How to send custom DHCP option on all Offer and Ack packets in kea?

I'm using the Kea dhcp server, and I want to use the DHCP options to send data to the server's clients. Following the instructions here, I listed the option with the "always-send": true ...
Jarred Allen's user avatar
-1 votes
1 answer
40 views

Trouble connecting to the internet with direct connection to the modem

I have a windows server that is directly connected to the modem but cannot connect to the internet with the APIPA self-assigned IP address. There's no router/DHCP as that's going to be the servers ...
SomethingsGottaGive's user avatar
-1 votes
1 answer
74 views

Should my device combine local DNS and static DNS?

Our linux based device was originally configured to use locally DHCP assigned DNS servers (in busybox/udhcpc.script). However after encountering a customer with this misconfigured, we changed the ...
Alex's user avatar
  • 103
7 votes
2 answers
3k views

ISC DHCP client (dhclient) alternative?

I've just seen the news on https://www.isc.org/dhcp : ISC has ended development on the ISC DHCP client as of early 2022. This client implementation is no longer maintained and should not be used in ...
kol's user avatar
  • 211
2 votes
0 answers
2k views

Why is my systemd-networkd not aquiring an IP address via DHCP?

On my notebook running Gentoo, I set up the following things: Kernel with all necessary settings and modules WPA_Supplicant Systemd Systemd-Networkd Almost everything works as expected, the ...
ahuemmer's user avatar
  • 121
0 votes
1 answer
5k views

How to disable /etc/hosts from resetting after reboot

Using Ubuntu 20.04 LTS on a Raspberry Pi and trying to setup a DNS and DCHP Server on it using DNSMasq Got to the point where I want to add static DNS results in the /etc/hosts file however when I ...
jacoboneill2000's user avatar
0 votes
1 answer
540 views

Disable the automatic adding of routes by DHCP

I have a Rapsberry Pi with PiOS. My idea is to install WireGuard on it and route all traffic through WireGuard. I have set the Allowed IPs to 0.0.0.0/0. I want the Pi to work on different networks and ...
Jonathan's user avatar
1 vote
0 answers
1k views

Multiple DHCP NIC and local LAN - Debian, Proxmox

tl;dr: How can i get 3 NIC to route, backup/failover and communicate together? I got a proxmox server with 3 NIC vmbr1: company lan - dhcp (engineering department) vmbr2: robotics network (static) ...
MightyMirko's user avatar
1 vote
0 answers
591 views

dhcp-relay cannot recieve DHCPOFFER packet from DHCP server in shared network

I'm using the dnsmasq service as a DHCP server. I have a bridged interface per node named br0 that has two ip addresses assigned to it. One is the public IP address and the other one is considered the ...
Mohammadreza Nasrabadi's user avatar
1 vote
1 answer
206 views

Is it legal for a DHCP relay agent to relay RENEWAL requests that were directly unicast to the "Server identifier" server?

I'm observing the following in a packet capture. Client -> Broadcast : DHCP Request Relay -> Client : DHCP Ack (Option 54 == Server) ... After T1 expires ... Client -> Server Identifier ...
user80551's user avatar
  • 111
-1 votes
1 answer
213 views

Configure new routing and run DHCP server in router to access internet

SO I am a beginner network professional , I was sent to do a routing in client location so they can access the internet .The routing was supposed to be done on cisco 3900 series router. the following ...
biplab 's user avatar
1 vote
0 answers
145 views

Windows PCs arping excessively for Domain Controller because they don't like the gateway given by DHCP

I've been administering my company's network for about 20 years. This is the first time this has ever happened and I've exhausted all means including my external network consultant and firewall ...
AbeyMarquez's user avatar
0 votes
1 answer
456 views

How do I install dhcp plugin for Strongswan on Ubuntu focal

I've installed strongswan, libstrongswan-standard-plugins and libstrongswan-extra-plugins packages and it seems that dhcp plugin is still not there. How do I install it? Is my only option to build ...
starteleport's user avatar
0 votes
0 answers
2k views

dhcp: lease expiration vs. infinite lease

As per RFC2131, when the lease expires the client has to stop using the IP address. So do I understand right that if the lease lifetime is set to infinite on the server, then the client does not need ...
Mark's user avatar
  • 259
1 vote
0 answers
913 views

Can not set static ip-adress on server (Ubunut Server 22.04)

I have been trying to set up my own cloud via nextcloud on an old laptop. So far it all works fine but the only problem is that I can not make it work with a static ip-adress. It works just fine with ...
memoki's user avatar
  • 11
1 vote
0 answers
2k views

DNSMASQ-TFTP failed sending file for PXE boot

2 month ago my PXE installation worked perfectly, now it can't send the file grubx64.efi to begin the PXE installation. juil. 08 08:03:05 install-server.my.domain dnsmasq[5913]: started, version 2.79 ...
Sommcrane's user avatar
0 votes
1 answer
3k views

Which DHCP is assigning IP addresses to WSL machines?

I run CentOS 7 inside WSL on Windows 11. My WSL IP is: [root@rbarak ~]# ip addr | grep eth0 6: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000 inet ...
boardrider's user avatar
0 votes
0 answers
632 views

Ubuntu 20.04 unable to set static IP address reverts to presumably thru DHCP

I have the following files in /etc/systemd/network (filename followed by content) on a Ubuntu 20.04 server: File: /etc/systemd/network/10-debug.conf [Service] Environment=...
Sunny's user avatar
  • 381
1 vote
0 answers
1k views

dnsmasq, one host on multiple vlans

I have dnsmasq configured to serve static dhcp on two networks; one on the primary interface and one on a vlan attached to the primary interface. The interface config looks like this: 3: enp2s0: <...
larsks's user avatar
  • 44.7k

1
2
3 4 5
43