All Questions
105 questions
-3
votes
1
answer
96
views
DHCP moved from [closed]
After connecting several Raspberry Pis running Ubuntu 23.10 to my switch, they are for some reason stepping on each others DHCP leases. DHCP is running on fpsense 2.7.2... Logs:
DHCPREQUEST for 192....
- 125
2
votes
0
answers
246
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 ...
- 21
0
votes
1
answer
723
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 ...
- 103
0
votes
0
answers
827
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=...
- 381
0
votes
0
answers
1k
views
Wireguard server: allow clients to communicate with devices local to the server through Wireguard (effectively using wireguard as a tunnel)
I've got a bit of a weird problem, and I'm not sure if I'm trying to fit a square peg through a round hole or if I'm just not sure how to ask the question I really want to ask.
At home, I have a ...
0
votes
1
answer
231
views
DHCP , DNS , FTP , what is the best way to run ? dockerize or just simple install on ubuntu? [closed]
I'm going to install DNS and DHCP and simple FTP service on my company network. My network has about 200 clients, what is the best way to install those services? on a docker environment or just simple ...
- 5
1
vote
0
answers
508
views
DHCP pushed route to custom table on Linux
Is there a way I can direct routes that I receive from DHCP to a specific routing table depending on what interface it was received on?
E.g. eth0 and eth1 are both configured by DHCP. I would like the ...
- 11
2
votes
1
answer
11k
views
How can I tell my Ubuntu 20.04 is running dhcp client?
I have a system that runs Ubuntu 20.04. However, it doesn't seem to be set as a DHCP client.
song@docker:~$ ps -ef | grep dhcp
song 7861 3124 0 08:50 pts/0 00:00:00 grep --color=auto ...
1
vote
1
answer
564
views
My DHCP client server (CentOS) cant get IP from DHCP server (Ubuntu)
Good day
kindly i have set up my DHCP server ( ubuntu Server) to provide IP for servers as client but the client is getting another IP out of submitted rang IP and i can't find any symptom in this ...
0
votes
1
answer
546
views
DHCP Pools on Ubuntu DHCP server not working properly
Mac addresses ending with "55:a3" and "56:2a" are also ending up in last pool
123 match if binary-to-ascii(16,8,":",substring(hardware, 5, 6)) = "55:a3"; ...
- 111
1
vote
2
answers
3k
views
Could not set DHCPv4 route: Nexthop has invalid gateway. Network is unreachable
/etc/netplan/00-installer-config.yaml
# This is the network config written by 'subiquity'
network:
ethernets:
ens192:
dhcp4: true
version: 2
/run/systemd/network/10-netplan-ens192....
- 113
1
vote
0
answers
3k
views
Override default gateway when using netplan DHCP
I would like to use DHCP for IP address assignment but I would also like to override/specify the default gateway. Is this possible in netplan? Something like the following (which doesn't work BTW)...
...
- 11
0
votes
1
answer
2k
views
Internet drops on Ubuntu ISC-DHCP-Client networking
i am having issues with the network connectivity on Ubuntu server 16.04. I am connected to Verizon Fios via Ethernet (it's defined as dhcp on the /etc/network/interfaces file.)
The DHCP Client that I ...
- 11
0
votes
2
answers
761
views
DHCP client stops working for specific NIC
Something weird is going on. I had a cable with VLAN 300 plugged into my ubuntu machine. And that worked fine, like this.
Jul 9 09:13:16 ruby dhclient[17696]: bound to 85.x.x.136 -- renewal in 1797 ...
- 115
4
votes
1
answer
4k
views
Set hostname using cloudinit for dhcp server: Systemd overrides cloudinit hostname
For a testing environment, I want to connect multiple VMs using DHCP with their hostnames as DNS entrys. The troubleshooting shows that my DNS/DHCP works. But the VM got registered using ubuntu as ...
- 548
1
vote
0
answers
399
views
Does Ubuntu 18/Linux respect the order of DNS servers?
Does Ubuntu/Debian (or Linux in general) respect the order of the DNS servers? Let's assume clean installation of Ubuntu 18.04
In Ubuntu 18, you can setup the DNS servers like this:
Aka does it take ...
- 137
0
votes
1
answer
1k
views
Enforce usage of VPN-provided DNS servers on Ubuntu 18.04
On a vanilla Ubuntu 18.04 headless server, the OpenVPN client is used to connect to a remote network in tap mode. The address, default gateway, DNS servers etc. are provided by a DHCP server on the ...
- 422
2
votes
2
answers
3k
views
DHCP not sharing Internet access
I have several Virtual Machines in Vmware ESXi 6.5 with 2 Network Groups.
Created a DHCP Server Machine on CentOs with 2 networks interface.
1 / vm network from which it takes a network and has IP ...
- 23
1
vote
0
answers
490
views
vSphere Customization Specification and Ubuntu 17.10
Has anyone noticed issues with #vSphere Customization Specification and #Ubuntu 17.10 (GNU/Linux 4.13.0-25-generic x86_64) – Now that the network settings are located in: /etc/netplan/01-netcfg.yaml, ...
- 53
0
votes
0
answers
57
views
One Server Occasionally Takes Down Network/DHCP. How to Diagnose?
We've got an Ubuntu 16.04.3 LTS machine plugged into our network that occasionally needs to automatically reboot itself. About 25% of the time, when it does this, it takes down the entire network. ...
- 121
1
vote
1
answer
966
views
DHCPv6 isn't updating DNS
I asked this on the Debian Users mailing list, but thought I'd ask here as well. I'm using Ubuntu 16.04 on ISC DHCP 4.3.3 and BIND9 9.10.3.
I'm having trouble getting my DHCPv6 server to update DNS ...
- 195
0
votes
1
answer
457
views
Is it possible to configure a DHCP server can fall back to be DHCP client when connected to another network?
Is it possible that a system running a DHCP server can become a DHCP client if connected to a network which already has a DHCP server running?
We have a situation where we want to run isc-dhcp-server ...
0
votes
3
answers
2k
views
How to put 127.0.0.1 ABOVE in /etc/resolv.conf with ubuntu + networkmanager + DHCP
Actually, on a ubuntu 16.04 server, my /etc/resolv.conf is :
# Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8)
# DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE ...
- 229
1
vote
0
answers
88
views
Vanishing network connectivity in HPC cluster
Hello and thanks to everyone in advance! My team and I have been plagued by the stability of a cluster that we use for scientific research. We have a lot of science and software engineering ...
4
votes
0
answers
601
views
DHCP Server Listing Host as "BAD_ADDRESS" and not Registering DNS
Question
Why is DHCP showing "BAD_ADDR", why does it think there is a Conflict, and why can't the host register its DNS name?
Devices:
DHCP Server = Server 2012 on bare metal. Also running DNS.
...
- 734
0
votes
0
answers
960
views
TFTP Server for multiple vlans
I have a linux dhcp/tftp server with multiple vlans serving a CMTS. The gist of it is in the CMTS, I tell the cable modems on what vlan I want them to get their address and configuration file from. ...
1
vote
1
answer
925
views
Iptables setup with 2 nic using DHCP(isc) and DNS(Bind9) issue on Ubuntu
Having an issue with my Linux as a gateway setup. Not sure what I'm doing wrong here.
What is expected:
Computers have services forwarded based on DHCP reserved ip addresses.
I can reach the servers ...
- 11
2
votes
2
answers
1k
views
Why does my Ubuntu virtual machine hosted in Hyper-V power on with a date in the future?
I have several Ubuntu virtual machine running within a Hyper-V server. The server is a Windows 2012r2 machine. The Ubuntu VMs are either Ubuntu 14.04 or Ubuntu 16.04 (the current LTS releases).
...
- 263
2
votes
1
answer
2k
views
Ubuntu 16.04 bonding config not working
I have a weird problem with my bonding setup.
Yesterday I tried to install Pi Hole on my Ubuntu 16.04 server and it messed up my bonding. I've uninstalled Pi Hole, but it's not working anymore.
My /...
- 31
3
votes
2
answers
5k
views
static network setup still using DHCP
I'm configuring an Ubuntu 14.04LTS server on our internal network. Everything works and runs as expected. Its assigned a static IP, here's /etc/network/interfaces
# The loopback network interface
...
0
votes
1
answer
1k
views
Dhcp Classless Static Routes hook error
I have a dhcp server that hands network information to vms of mine. It works fine for centos6,7 , and debian 7 clients. However it fails for Debian 8 and Ubuntu 16.04 clients.
For the ones where it ...
- 265
1
vote
0
answers
58
views
Why was the previous authenticity of the host ignored?
I'm on Ubuntu 14.04 Desktop.
I have just logged into other machine (Ubuntu 14.04 Server) using ssh in one terminal. I'm still connected.
When I did scp in another terminal (opened earlier) to move a ...
- 75
0
votes
2
answers
460
views
Create smaller subnets from large subnet
My network is 10.10.0.0/16. I would like to break this up into /24s.
My environment:
I use /etc/hosts with dnsmasq for DNS and isc-dhcp-server for DHCP on an Ubuntu 14.04 server (gateway, router) ...
2
votes
1
answer
2k
views
DHCPD configuration by interfaces
I have two interfaces on a machine running Ubuntu 14.04 LTS. Which has two different interfaces namely eth0 and eth1.
I need to give IP addresses to the clients by the interfaces.
For example,
Any ...
- 155
19
votes
2
answers
132k
views
How do I manually release a DHCP lease on the DHCP server itself?
I have been doing some VM testing. I have created and destroyed a large number of VMs on my subnet to test fresh provisioning via puppet. However, it looks like Ubuntu doesn't free a DHCP lease when ...
- 2,323
1
vote
1
answer
35
views
set host-name failed on Ubuntu vivid
With Ubuntu vivid, I cannot bind the hostname of my server with the IP address gotten by a DHCP server
I tried to add in dhclient.conf (and reboot)
set host-name "myserver";
But, still doesn't work....
- 632
1
vote
1
answer
547
views
Using Clonezill/DRBL DHCP as main DHCP server
Right now in my department we are running a DHCP server on some older hardware that is looking like it might fail soon(ish) and is also running CentOS 4. We'd like to upgrade to a new DHCP server but ...
- 91
0
votes
1
answer
10k
views
Setting up stateful DHCPv6 on Linux
I want to set up a DHCP server on my local network for IPv6 that issues addresses and further information like DNS/NTP and so on. From my ISP I got the IPv6 Prefix which I will refer to as <prefix&...
- 103
0
votes
1
answer
931
views
Ubuntu DHCP Server not assigning itself an address
I am setting up a virtual environment inside an ESXi server. I have a version of Ubuntu Server running isc dhcp.
When the server boots up I issue the command ifdown eth0 followed by the ifup eth0. ...
- 103
0
votes
0
answers
1k
views
How to configure DHCPv6 and DNSv6 configuration in Ubuntu 12.04?
I'm planning to configure DHCPv6 and DNS server in my network.
I would like to understand whether both DHCPv4 and DHCPv6 can be configured using isc-dhcp-server service?
When i tried nslookup ...
- 356
3
votes
1
answer
11k
views
How to get the DHCP-controlled DNS domain name for my Ubuntu machines in a Windows network?
I've been going in circles for a while trying to figure this out. I have a number of Ubuntu machines (some virtual) on a Windows network. From a Windows machine, I can ping or nslookup the Ubuntu ...
- 149
0
votes
1
answer
459
views
Custom Live Boot PXE ISO Script
Currently I am using an open source PC auditing software called Open-Audit to audit PCs my company receives off lease from school districts. The software uses snmap to pull hardware information over a ...
1
vote
1
answer
2k
views
Ubuntu 14.04 can only access outside networks if using DHCP, not static IPs
I am configuring some server on Ubuntu Server 14.04 (no GUI) and I am have the following configuration:
auto lo
iface lo inet loopback
## Management network eth0
auto eth0
iface eth0 inet static
...
- 200
6
votes
5
answers
22k
views
Multiple DHCP uplinks - How to ignore DNS and default route on all but one?
A multi-homed box needs more than one uplink to be configured for DHCP. It needs to ignore default-route and DNS for all but one DHCP uplink.
There is a similar question here [ Debian interfaces file ...
- 3,502
5
votes
2
answers
3k
views
How to correctly configure DNS usage in Ubuntu? Authoritative answers without RA flag are ignored
I have latest clean Ubuntu 14.04.1 64-bit from official website installed in Virtualbox. I connect to a VPN network using vpnc that sets 2 DNS servers using DHCP:
user@virtual:~$ cat /etc/resolv.conf ...
- 3,955
2
votes
2
answers
8k
views
isc-dhcp leases file never cleaned
When running isc-dhcp the leases file seems to grow indefinitely (several hundred MB). If I restart the isc-dhcp service, the file shrinks to 1.5MB.
How can I have isc-dhcp flush expired records ...
- 951
2
votes
1
answer
207
views
Two LAN cables when using Remote Access Card?
I recently bought a HP MicroServer N54L and a HP Remote Access Card.
Connecting to the server over a KVM viewer for BIOS setup etc. works fine, but when it comes to installing Ubuntu 14.04. the ...
- 65
1
vote
0
answers
131
views
force dhcp server to always run
I have an Ubuntu machine with two Ethernet network interfaces and on one of them I am running a DHCP server (isc-dhcp-server).
I noticed that the server daemon stops running whenever I suspend the ...
- 235
0
votes
1
answer
178
views
DHCP server hardware [closed]
I have a user who needs to set up a DHCP Server for about 8000 users. Can I set it up on regular PC hardware. So far we have not set it up for more than 200-300 users.
Are there anything which I need ...
- 685
5
votes
2
answers
4k
views
Assign fixed IP address via DHCP by DNS lookup
Preface
I'm building a virtualization environment with Ubuntu 14.04 and LXC. I don't want to write my own template since the upgrade from 12.04 to 14.04 has shown that backwards compatibility is not ...
- 277