Questions tagged [dhclient]
dhclient is the DHCP client for Linux and UNIX, created by the Internet Software Consortium. It is used to configure network interfaces using DHCP or BOOTP protocol, or can be used to assign static configurations.
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One-shot DHCP request with systemd-networkd
How to/is it possible to make a one-shot DHCP request without writing/modifying a .network file for the interface?
With dhclient, you could just run dhclient enp23s0f4 to obtain an IP address. I am ...
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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 This client implementation is no longer maintained and should not be used in ...
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How to configure IA_PD prefix length with dhclient?
My home internet connection is going through a router provided by my ISP. It gets a ::/56 ipv6 prefix assigned dynamically by my ISP every night.
Behind that router I have a debian bullseye box for ...
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OpenVPN clients' DNS, unwanted ip routes added by dhclient
I've set up an OpenVPN gateway that provides access to a large cloud of IoT devices. Each device has a unique certificate, and upon connection, I grab the "common name" from the cert to ...
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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 ...
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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 ...
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dhclient: What does "RTNETLINK answers: File exists" Mean?
I wanted to update the DHCP lease of an Amazon EC2 instance, so I executed the following command:
user@host:~$ sudo dhclient
Following that, the system's DHCP lease is updated successfully updated. ...
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Debian 10 Buster can't renew DHCP as client, when IPv6 is disabled
After I upgraded Debian 9 to 10 Buster server lost network connection after 24 hours since reboot, I think problem is it can't renew IP address from DHCP server.
In /var/lib/dhcp I see the file ...
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Shouldn't dhclient confirm its lease after a carrier loss?
I'm investigating an issue with a Ubuntu server acting as the Internet gateway for a branch office stopped working after being switched to a new Internet connection.
The IP address on the external ...
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AWS time traveling issues with dhclient
I am a QA software engineer working on integration tests that require changes on the system clock to simulate the pass of the time. When running those tests on AWS EC2 instances I got unexpected ...
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My network interface changes names, so DHCP / dhclient cannot operate on it
On some ArchLinux servers I've switched from dhcpcd to dhclient, but the servers are not receiving IP. Upon inspection with journalctl I see that, on all occasions the IP was not received, dhclient ...
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different DHCP behavior between machines using NetworkManager and not using NetworkManager
can anyone please shed some light on the differences I list below. And maybe explain why NetworkManager does it differently. And please advise if we can change NetworkManager to behave more like the ...
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Libvirt VM Networking fails to start up after upgrading host from Ubuntu 18.04 to 20.04
I upgraded a server from 18.04 to 20.04. I am using libvirt/kvm to host a number of VMs. Some of the VMs failed to reconnect to the network after the upgrade.
Two VMs in question run Ubuntu 18.04 and ...
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How to include vendor-specific option 17 suboptions 11, 12 and 13 in DHCPv6 solicit/request using dhclient
My request is to include option 17 sub-options 11, 12 and 13 in DHCPv6 solicit/request and I configured the same in dhclient6.conf on my Ubuntu as below.
send dhcp6.vendor-opts 00:00:0d:e9:00:0b:00:06:...
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How to pass a vendor-specific options to a DHCP server using dhclient?
I need to send vendor-options to DHCP server using dhclient (ISC).
As I understand I need to describe that options in the dhclient.conf.
Do I need make new "space" for options? Or I can do "send"?
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Different lease duration for dhcp clients
Is it normal in Windows implementation of DHCP Server and DHCP Client that some clietnts gets strange long lease expires time like 15 days?
,,Lease duration for DHCP clients'' setting in DHCP Server ...
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2 servers show different behavior when DHCP sever goes down
i dont have any control of the DHCP servers on my network and every 2 weeks or so there is an outage of a few hours where my CentOS 7.8 servers do not get responses to DHCP renewal requests. As far as ...
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isc-dhcp dhclient request address endless loop
when a Linux Mint 20 virtualbox VM requests the network config to the home LAN router DHCP through isc-dhcp client with the stock /etc/dhcp/dhclient.conf config file everything runs fine:
(BTW 192.168....
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Why is dhclient issuing a unicast DHCPREQUEST every ~15 seconds instead of at T1/T2 timers?
I am running a CentOS 6.2 server as my gateway and firewall, while also providing some internal services. This is a setup I have had for years using various hardware and distributions (redhat based). ...
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Request an address from a range of IP-addresses using dhclient dhcp-requested-address
I am in a situation where I need myDevice (ubuntu), when connected to router, to have any IP address in the range of 192.168.1.20 to 192.168.1.40. I am aware that adding the line
send dhcp-...
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CentOS 7 is not setting my gateway from DHCP
I have a Minimal Install of CentOS 7.
I have disabled the Network Manager as I want to setup my network the "old school" way.
systemctl stop NetworkManager
systemctl disable NetworkManager
...
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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 ...
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Renewing DHCP lease without losing static IPs? (dhclient removes static IPs)
I have this interface, with DHCP and some static IPs:
$ ip addr
2: enp3s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether e0:d5:5e:...
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DHCP clients: Where is the hostname going to come from
We are building a private cloud here, VMs have at least 2 NICs, sometimes 3 or 4, each may be statically configured for IPv4 and/or IPv6 or be configured by DHCP or a combo of the two.
Yes it's a ...
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resolv.conf after reboot on CentOS 5.5 EC2 instance
I'm having trouble getting my CentOS 5.5 EC2 instances (both i386 and x86_64) to properly populate resolv.conf after booting. No matter what I do, I end up with the default EC2 resolv.conf:
; ...
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Debian Server: DHCP keep IP on reboot
I've a Debian server running with some static IPs and a public IP, all provided by the same ISP on a FTTO connection.
Now I've noticed if I unplug the cable between the server and the ISP ONT/ONU and ...
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eth0 with static ip gets shutdown after dhclient fails
I have a Nvidia Jetson TX2 SoC in an Connecttech Astro carrier board running Ubuntu 16.04. The carrier has two Gigabit Ethernet ports which I would like to configure with static IPs. In system ...
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vbox cloned centos7 fix same ip new to have different ip from cloned one
I cloned centos7 vm in virtualbox, but they ended up with same ip address. My network preferences are my created NAT network with: 10.0.2.0/24
Both vms uses this network i created, but they have same ...
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Networking service timeouts every second restart
The setup
My debian server at online.net is running a dual stack ipv4/ipv6
# /etc/network/interfaces
auto lo
iface lo inet loopback
source /etc/network/interfaces.d/*
There are 2 files in /etc/...
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dhclient: No broadcast interfaces found, but eth0 is up and broadcast
I'm experiencing a common problem with dhclient. But I wasn't able to find a clear solution to this problem.
System:
ReadyNas RN104
Stock Debian for armhf
Just upgraded to Debian Jessie
Self-built ...
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How to remove only IPv6 addresses with iproute2?
I'm trying to write an application that can change the IP address of the local machine. When doing some experimentation, I've noticed that if I freshly connect to a wireless network, I am assigned an ...
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Search option in resolv.conf getting overwritten by prepend statement in dhclient.conf
I have setup a DNS server for my department which is running FreeBSD 10.2. It is currently connected to the campus internet and receiving its address via dhcp, so /etc/resolv.conf looks like this:
#...
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Configuring linux to be visible in microsoft DNS domain
I've been trying to have one of our linux box available in the windows domain. The linux box is a ubuntu server without gui or X installed. All manipulations are done from ssh.
Linux box:
hostname: ...
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Register A records for my Linux box on my Windows 2008 DNS/DHCP server
I've a network which is mainly Windows: Windows 2008 server (with DNS/DHCP as well as AD), and various mainly Windows machines (servers, XP, 7). I know trying to add few Linux boxes, and can't make ...
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dhclient doesn't set default gateway
I'm running a few Ubuntu 16.04 VMs in the Azure cloud. Whenever I reboot a VM I have to set the default gateway manually.
The gateway should be set by dhclient. I activated the debugging and get this:...
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Get rid of default "search" entry in "/etc/resolv.conf" on Amazon EC2 Fedora instance
Case of an Amazon EC2 Fedora 23 instance.
The file /etc/resolv.conf which determines how DNS lookups are performed by glibc resolver (see man resolv), looks as follows:
; generated by /usr/sbin/...
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Cannot renew DHCPV6 lease in SLES12
I need to renew the lease of a certain SLES12 box. The machine is configured to use IPv6 only and so far I have tried the following:
From here:
dhclient6 -r -v eth0 && rm /var/lib/dhcp6/...
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How to configure dhclient on CentOS to get IP from a specific DHCP server
I have a situation where I am able to launch CentOS 6.6 images on a subnet such that the VM instances get their IP addresses from the virtual gateway of the subnet. Now this gateway has gone wonky and ...
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ubuntu 14.04 LTS change dhclient lease file location
I cannot find how to change dhclient lease file location. By default (and currently) it is in /var/lib/dhcp, but I want this file to go to another place.
I did ps ax | grep dhclient and got this ...
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Issue with RHEL7 and disabling NetworkManager
Okay community, let's see if we can figure this one out, cause I'm out of answers.
Where I work I am setting up a bunch of RedHat Enterprise Linux servers. There is a collection of RHEL6 and RHEL7 ...
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DHCP attribution without DHCP client
j'ai un serveur DHCP qui attribue des IP selon les adresses MAC des clients.
J'ai un client qui n'a pas de client DHCP installé (pas que je sache).
I have a DHCP server (on linux) which gives IP ...
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Supersede default route
I have two network interfaces eth1 and wlan0. I would prefer all outbound traffic to go through eth1 before wlan0, but if eth1 is not up, and then wlan0 should handle the traffic.
Both interfaces get ...
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Debian 7 how are IPv6 link local addresses set?
It seems like when dhclient runs on eth0 I get an IPv4 address from the DHCP server and a Scope:Link IPv6 address attached to eth0:
inet6 addr: fe80::a00:27ff:fed0:4d41/64 Scope:Link
But I can't see ...
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How to request dhcp (using dhclient) on a virtual interface (i.e. eth0:1)
This seems to work fine:
dhclient eth0
ifconfig eth0:1 192.168.1.105 up
But not this:
ifconfig eth0 192.168.1.105 up
dhclient eth0:1
Is there any way to get dhcp on a virtual address?
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Can we force dhclient to not renew ip rules?
I've overridden the ip routing rules on my RHEL machine by adding custom logic in a new script ifup-local that is run immediately after a new interface is attached.
/etc/sysconfig/network-scripts/...
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"ifup eth0" causes dhclient to bring up more than one interface
Can someone tell me why dhclient is not respecting to only handle the one interface it has been passed?
I've seen this multiple times over the years; never figured it out - it's not related to ...
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Suddenly unable to obain IP address but eth0 port blinking rapidly
After a server restart, the server is unable to obtain an IP address through a wired ethernet interface, neither automatically nor manually.
However the green light on the back of the machine where ...
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how to Check for dhclient in Directadmin [closed]
I have installed CSF firewall in CentOS 6 64-bit on Directadmin
dhclient appears to be running which suggests that the server is obtaining an IP address via DHCP. This can pose a security risk. You ...
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CentOS 5 domain-search from DHCP server ignored by dhclient
I have a DHCP server running ISC dhcpd which offers the option domain-search "domain.local"; option.
This is being ignored by a particular CentOS 5 dhclient which is removing the search parameter in ...
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Linux:/sbin/dhclient to bind to a specific interface?
I'm running RHEL5.5 and have several network interfaces (eth0, eth1, eth2) on the machine. I wish to make /sbin/dhclient bind its UDP port 68 on specific interfaces (eth0 and eth2) but when I do '...
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