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Questions tagged [dhcp]

The Dynamic Host Configuration Protocol (DHCP) is an auto configuration protocol used on IP networks.

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

DHCP allows for computers to be configured automatically to communicate with each other over an IP network without the need for setup by a network administrator.

It keeps track of the computers connected to the network with a central database and prevents two computers from accidentally being configured with the same IP address.

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How to force ALL of the DHCP Clients to renew?

Is there any network broadcast call or something that can force all the connected DHCP clients to renew their addresses immediately? And if not, why not? Surely this functionality has been desired by DHCP administrators from the date it was born.…
Mike Wise
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How can I check dhcpd.conf against syntax error without running dhcpd?

I need to make sure there are no syntax errors on dhcpd.conf. If there are errors, I want to get what they are. I can check for syntax errors with this command: dhcpd -cf /path/to/dhcpd.conf but that prints a lot of information in addition to the…
ibrahim
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Can't ping a local VM from the host

My work laptop is is a member of a domain (the OS is Windows 8). Created a new VM, locally on this laptop (using built-in Hyper-V). DHCP is provided by the domain and all IP addresses are assigned by the DHCP, both to the host and to the VM. The VM…
user2690101
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Detecting a change of IP address in Linux

Does anyone know a way to detect a change of IP address in Linux. Say I have dhcpcd running, and it assigns a new IP address, is there a way I can get a notification when it changes? I can't use D-Bus, because this is an embedded ucLinux build that…
Joel Holdsworth
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Why DHCP client listens on port 68?

If suppose client does not listen on 68 port,when DHCP server receives the request, it can send it to the address from where it received request (with ephemeral port chosen by client at time of sending), then why does protocol specifies client to be…
avd
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VMWare - Virtual operating system static IP address

What is the best way to have a virtual operating system have a static IP address in VMWware. I would like to keep the IP address static since it is a virtual server.
Daniel Kivatinos
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How can dhclient be made namespace aware?

I am using namespaces to separate a few physical interfaces on a server. The routing works perfectly. Also I have a folder for each namespace in /etc/netns/ e.g. /etc/netns/namespaceA/resolv.conf so that DNS works fine as well. The problem arises…
Jimmy88
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Why are DHCP Offer and Ack broadcasted?

Why can't the server use the destination IP address of 0.0.0.0 as is used in source IP of DHCP Discover and Request? It can use the MAC address of the client learnt from DHCP Discover and Request to direct the frame to the appropriate client…
Bruce
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Kubernetes MetalLB External IP not reachable

I can't access to Network IP assigned by MetalLB load Balancer I created a Kubernetes cluster in k3s. Its 1 master and 1 workers. Each one has its own Private IP. Master 192.168.0.13 Worker 192.168.0.13 I Installed k3s with INSTALL_K3S_EXEC="…
Rahul Sharma
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Run dnsmasq as DHCP server from inside a Docker container

I'm trying to get dnsmasq to operate as a DHCP server inside a Docker container, issuing DHCP addresses to machines on the host's physical network. I'm using the Alpine Linux 6MB container from https://hub.docker.com/r/andyshinn/dnsmasq/. It works…
Josh Wulf
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Set static ip if not obtained from DHCP (script)

I work on embedded device with linux on it. I want to use DHCP client first, but if there will be no answer from DHCP Server I want to set static-default IP. I suppose it shouldn't be complicated, but I haven't found strict answer. I'm thinking…
Bartlomiej Grzeskowiak
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How to configure a Docker container for acquiring DHCP IP/s from dhcp server running on ESX

My host is SLES12 VM running on an ESX server. VM Host has interfaces which acquire DHCP IPs from the DHCP server running on ESX. In my docker container (docker image: opensuse) I am running a NFS server and hence need external access. I want the…
Anupam
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Broadcasting UDP packet to 255.255.255.255

first time poster, hopefully this is an easy one: I need to send a broadcast packet to a piece of hardware which, when it powers up, is on a different subnet than my machine, in order to tell it to reset its IP address to one that's on my network. …
GP Hoit
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Python: check whether a network interface is up

In Python, is there a way to detect whether a given network interface is up? In my script, the user specifies a network interface, but I would like to make sure that the interface is up and has been assigned an IP address, before doing anything…
Ricky Robinson
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Android - Ethernet - Programmatically

I am developing an Android app which will be used by custom devices which will have ethernet support (and also wifi). The app has to enable a settings activity for Ethernet. Please NOTE that these settings have to be run by the app and not by the…
MTurPash
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