Questions tagged [dhcp]
DHCP is an auto configuration protocol used on IP networks.
2
votes
0answers
34 views
How to configure ipv4 Link-Local on Linux with systemd-networkd without violating RFC3927 specifications?
I'm using an embedded device with Linux 4.9 and systemd.
I configured systemd-networkd in this way:
[Match]
Name=eth0
[Network]
DHCP=v4
[DHCPv4]
UseHostname=false
How can I setup Link-Local only ...
0
votes
1answer
27 views
DHCP Server IP Conflict Detection
I am setting an Wifi Access point. A common problem about this is that router or etc. could be giving similar IP address to client devices which will cause problems.
My question here is that is there ...
1
vote
2answers
53 views
Which program is releasing Linux's Dynamic IP address, if dhclient already killed?
After dhclient was killed, in short term, I didn't see the Dynamic IP lost. Then, after a weekend, the Dynamic IP address is gone.
Just wonder which program released it.
-1
votes
2answers
31 views
How to configure dnsmasq to use /etc/hosts instead of “dhcp-host”?
I have been able to configure static ip for specific client in /etc/dnsmasq.conf by using "dhcp-host":
http://manpages.ubuntu.com/manpages/cosmic/en/man8/dnsmasq.8.html
I would like to use /etc/...
0
votes
0answers
53 views
dnsmasq: not giving name to the DHCP lease because the name exists in /etc/hosts
I am running dnsmasq on Centos 7.
dnsmasq is acting both as DNS and DHCP. The DNS returns the correct ip based on the hostname. However the DHCP doesn't assign the ip address based on the /etc/hosts ...
0
votes
0answers
41 views
systemd-networkd - wlan no IPv4 address via DHCP
Setup
I'm trying to set up a Wifi modem to connect to a WPA wireless network. The embedded target platform is running Linux 4.9.x, systemd-networkd (v237), systemd-resolved, and wpa_supplicant.
I'...
0
votes
0answers
42 views
How to flush all the DHCP leases with virsh. So all not just one with net-update default delete ip-dhcp-host
OS: Fedora 28
KVM
So I am trying to delete all the dhcp leases with virsh, so all of them at once not one by one or any one in particular. I know that you can use net-update default delete ip-dhcp-...
1
vote
1answer
34 views
Debian 8(Jessie) started before DHCP server results in no network connection
Recently we got a power outage and our debian 8 Raspberry Pi did not reconnect to the internet.
We noticed that our DHCP server was very slow to start > 5 min. In this time the Pi was already up and ...
1
vote
2answers
26 views
servresolv.conf become blank when system is running
I use dhcpcd to manage this file.
First, start dhcpcd service, and the file has something with namesever.
All things can be done correctly.
But this file will become blank after a while.
I try ...
0
votes
2answers
32 views
dhcpcd service disabled yet dhcp works
I am using Arch (Manjaro) with Gnome. My organisation recently switched to a DHCP server. So we all had to switch our computers from static to DHCP.
What I noticed is that the dhcpcd service is ...
0
votes
2answers
53 views
dhclient command does not allocate ip address to my interface
So I was trying to access a website through my browser but I couldn't.
So I issued the ifconfig command to see if there was something wrong with the IP address
I noticed that the interface enp0s3 ...
1
vote
0answers
21 views
Mobile Broadband for only one host
What is the easiest method to configure a mobile broadband connection in a way that:
no default route is added
a route to a specific host is added
The connection is managed by Network Manager. The ...
0
votes
0answers
53 views
dnsmasq does not hand out IP addresses
I am trying to learn about networking, specifically, what I am currently trying is creating a private network that runs behind a NAT that connects to my main router.
The way I've though of it is as ...
0
votes
1answer
99 views
Problem with Wpad file in Mozilla Firefox
I have this wpad.pac
function FindProxyForURL(url, host) {
if (isPlainHostName(host) ||
shExpMatch(host, "*.local") ||
isInNet(dnsResolve(host), "192.168.0.0", "255.255.255.0") ||
isInNet(...
0
votes
1answer
33 views
Change default gateway & assigned IP via script
I need some pointing in the right direction as I've tried a lot of different things over the past few days without success. I'm new to using bash and linux in general.
I'm trying to detect when the ...
1
vote
1answer
59 views
exclude local addresses in wpad
I have a proxy Ubuntu 18.04, with squid 3128 and apache2, and I publish the auto configuration file proxy.pac with the option dhcp 252.
The file has the following contents:
function FindProxyForURL(...
0
votes
2answers
279 views
Systemd-networkd: Run script after DHCP client aqcuires new address
I am on ubuntu 18.04 server. I need to run a script that updates an IP address on CloudFlare (kind of DynDNS script). In previous versions I could do this with a DHCLIENT exit hooks for the interface ...
1
vote
1answer
36 views
How to make dhcpd recognize a new interface without restart
I'm working on automatizated virtualization but currently i'm stuck with setting up the DHCP server. The problem is, every time i create a virtual machine, i have to restart the daemon to register the ...
3
votes
1answer
277 views
Permanent outgoing IP address with enabled DHCP [closed]
I have some problems making my outgoing IP address configuration permanent.
I googled a lot and I do not find configuration that work for me.
Assume my network is 192.168.1.0/24 with default gateway ...
0
votes
0answers
67 views
block LAN device by mac address using dnsmasq
My router is using dnsmasq as the dhcp server. I currently see a device identified as EPSONBBE74B which is receiving a dynamic IP address. I don't recognize that device. Nobody here can find it. I ...
0
votes
0answers
13 views
Avoid network start timeout when upping bridge on bootup
I have a laptop that has wifi and cable. The ethernet
interface is called enp0s21f5 and I need to have it
under a bridge to be able to connect tap/tun from kvm
virtual machines. The networking is ...
1
vote
1answer
46 views
Is it possible to set up a secure PXE server available on the internet? [closed]
Yesterday, I successfully installed a working PXE server on a Raspberry Pi and managed to boot from it on my home server on my local network.
My goal is to build a cluster with a master node hosted ...
0
votes
0answers
26 views
Share my computer's connection
I have tried several methods and none worked out for me, so I come here to ask for help. I have two network interfaces:
eth0, that is connected to my office network and gets its IP from a remote DHCP ...
0
votes
2answers
46 views
Is there a way to cache the last IP assigned on DHCP clients and use that if the DHCP server is down?
I would like my DHCP clients (CentOS 7) cache the last IP assigned (reserved) for them and use that if the DHCP server is down.
Below is the current network interface configuration of my DHCP clients:...
0
votes
1answer
39 views
Name or service not known in DHCP subnet [closed]
I'm trying to setup proper ip forwarding within a DHCP subnet generated through a host with two different netowrk adapters.
My current situation is the following:
First node with two networks ...
0
votes
2answers
39 views
Can't sniff / initiate DHCP renew
I am running
sudo tcpdump -i enp0s31f6 -n port 67 and port 68
on one terminal and running
sudo dhclient -r
on another.
During this, I see nothing on first terminal.
What I am doing wrong?
...
0
votes
1answer
42 views
DHCP DNS and Domain resolution NetworkManager
My environment is following, all cabled with gigalan, all latest Debian 9, vm with virtualbox on 2 different physical hosts.
A mikrotik internet router which acts as DHCPD
I configured it setting ...
1
vote
1answer
213 views
Why do I have so many /etc/resolv.conf.dhclient-new.xxxx files?
I don't understand why I have on one machine (debian 9) so many /etc/resolv.conf.dhclient-new.xxxx files
my /etc/dhcp/dhclient.conf
option rfc3442-classless-static-routes code 121 = array of ...
0
votes
2answers
483 views
CentOS 7 DHCP Client - How to use “classless-static-routes” (“code 121”)?
According to this answer...
https://unix.stackexchange.com/a/457577/61742
... I can use the following configuration to use pushed routes from my DHCP server in my DHCP client by placing in the /etc/...
2
votes
0answers
235 views
How to use ISC KEA DHCP to inform “DNS” and “GATEWAY” to my DHCPv4 clients?
To illustrate I will inform the configuration of my ISC KEA DHCP (DHCPv4) and my DHCP client. Below is the configuration I am currently using for my ISC KEA DHCP (DHCPv4):
$ cat /usr/local/etc/kea/...
1
vote
2answers
53 views
Why is DHCPD offering wrong lease times?
I have DHCPD on OpenBSD 5.8 running and experiencing a weird issue.
I set the lease time as follows in /etc/dhcpd.conf:
max-lease-time 7200;
default-lease-time 7200;
This should be 2 hours.
When I ...
4
votes
3answers
710 views
Is it possible to use a single DHCP server to push completely different ranges of ip to different network interfaces in different LANs?
Is it possible to use a single DHCP server to push completely different ranges of ip to different network interfaces in different LANs?
EXAMPLE:
I have the Severs #1 and #2.
Severs #1: A DHCP ...
2
votes
0answers
42 views
Is there any hook for isc-dhcp-server returning the DHCPACK to client? [closed]
I would like to run a script in the server after the isc-dhcp-server send the DHCPACK packet to client.
Only now I get it solution is that running a script to retrieve the dhcp log, but it is not ...
1
vote
1answer
496 views
How can I use ISC KEA DHCP (DHCPv4) server to push routes to clients?
QUESTION:
I have an infrastructure with 5 servers (Server #1, #2, #3, #4 and #5). I am trying to use a server (Server #5) with ISC KEA DHCP (DHCPv4) ( https://kea.isc.org/wiki ) to push routes to ...
1
vote
1answer
29 views
Arch i3wm valid ip, DHCP problem
related but solved by workaround: In Archlinux, it has a valid ip, but no connection could established
So my arch system has gone "offline" some time ago.
I didn't bother to much because I used the ...
2
votes
1answer
394 views
Use dnsmasq to pushing routes to my clients on a small local network
I'm trying to use dnsmasq to pushing routes to my clients on a small local network.
However my clients (Server #1, #2 and #3) can not use these routes. The dnsmasq service is running and I do not ...
0
votes
2answers
160 views
wpa_supplicant doesn't get new IP when re-associate?
I am struggling to setup my wlan so it can re-associate to another hotspot and renew its IP automatically. I have found a similar question but nobody responded.
I am using Debian stretch. The first ...
3
votes
1answer
181 views
new IP address whereas DHCP lease time not out
My embedded system uses systemd and gets its IP address via DHCP. The DHCP server uses lease time to give the same IP unique address to every computer on the network if lease time is respected.
The ...
0
votes
0answers
58 views
debian stretch : how to automaticaly retry dhcp after network failure on boot
I recently had a VM that unexpectedly rebooted but the network was unavailable at that time:
Jul 7 12:18:44 tuf ifup[625]: DHCPDISCOVER on ens3 to 255.255.255.255 port 67 interval 17
Jul 7 12:18:44 ...
-1
votes
1answer
56 views
Linux IP resolution issue [closed]
I uploaded a new Ubuntu based MISP virtual machine on my VMWare ESX.
Configured it to use DHCP and IP address 192.168.10.6 was assigned to it.
I am able to get the dashboard of the MISP application ...
0
votes
1answer
157 views
DHCP server does not include NTP server addresses in the DHCP ACK message
I am capturing DHCP packets with tcpdump. The client sends a DHCP request asking for the DHCP configuration which contains a request for NTP servers but in the DHCP ACK message sent by the router ...
0
votes
0answers
150 views
trying to redirect all traffic with iptables but not working
I have a raspberry pi that is set up as an access point. It is NOT connected to the internet. I followed this tutorial until the section about bridging. (I don't have my raspberry pi connected to ...
0
votes
0answers
46 views
Network interface getting DHCP address while configures as static
I have a Linux server running Debian 9 with a single network interface.
I have configured it to have a static ip address which worked for about a year.
After a recent reboot however, it received a ...
1
vote
1answer
164 views
systemd-networkd dhcp_hostname option
I have configured systemd-networkd to setup my networking, I have created vlan10 and i want to client send hostname to DHCP to register in my DDNS server so question is does networkd support ...
1
vote
1answer
2k views
How to get Pi-Hole to work with IPv6?
At home I have installed Pi-Hole on a Fedora 28 machine, and it is now working properly serving IPv4 addresses via DHCP, acting as the DNS server, and blocking IPv4 addresses as appropriate. However, ...
0
votes
1answer
627 views
Does openwrt have a dhcp client?
I was surprised that building a default open wrt config created an image without dhclient, After some digging we found odhcpd package for use as the dhcp server but I still can't find any package that ...
0
votes
2answers
184 views
Linux respond with source address of a virtual interface
Hoping this is the correct forum.
I have a Linux (Centos 7) server with Quagga (for BGP) and DNSMASQ (for DHCP) installed. We are running DHCP services over BGP for redundancy.
Currently, the ...
1
vote
1answer
495 views
UFW/IPTABLES not blocking DHCP UDP port 67?
I am running ubuntu 16.04. I have ufw installed and enabled. I also have isc-dhcp-server installed. I have not opened up UDP port 67, yet DHCP clients still seem to be able to obtain DHCP leases from ...
0
votes
0answers
97 views
How to renew the IP with dhcp client if the AP changes the IP range without disassociate the clients
We are executing the dhclient for our Wi-Fi interface.
When the Wi-Fi disassociates from the AP, we have a script that renews the IP automatically from the new AP:
cat dhcpaction.sh
#!/bin/sh
...
0
votes
1answer
209 views
DHCP offer delay
Initial data:
1. Two DHCP servers:
First:
Description: Debian GNU/Linux 6.0.10 (squeeze)
Release: 6.0.10
Codename: squeeze
Second
NAME="Debian GNU/Linux"
VERSION_ID="8"
VERSION="8 (...
