Dynamic Host Configuration Protocol (DHCP) allows computers on the same network to automatically obtain a unique IP address.

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45
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5answers
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How can I stop Mac OS X overriding my hostname when I receive a DHCP request on Snow Leopard?

Whenever I go on a network where the DHCP server assigns hostnames then it overrides the settings I've set for my hostname on my Mac in the "Sharing" section of System Preferences. How do I stop this ...
25
votes
3answers
50k views

Why is Windows' default IP address 169.xx.xx.xx?

My Windows system got an 169.xx.xx.xx IP address the other day, and I fixed the issue, but why did Microsoft chose this address as the default? Why not 1.xx.xx.xx or 255.xx.xx.xx? Did one guy at ...
15
votes
3answers
33k views

Release/Renew IP Address via Terminal in OS X

I am looking to release and renew my IP address in OS X 10.4 using Terminal. Essentially, I need the OS X equivalent of Windows: C:\> ipconfig /release C:\> ipconfig /renew However, I need the ...
13
votes
6answers
28k views

How to force Windows 7 to ask for a “fresh” IP address from DHCP server?

I'm troubleshooting a certain issue with my DHCP configuration, and need my Windows machine to ask for a "fresh" IP address, so I can see which address DHCP server gives by default. When I do ...
12
votes
7answers
9k views

Why is my subnet mask 255.255.255.255?

I have a modem which used for internet broadband and I got an IP address in the 'A' class 10.x.x.x and have netmask 255.255.255.255. What does 255.255.255.255 mean exactly? When I try to sniff with ...
10
votes
6answers
10k views

Why is my router assigning the wrong address via DHCP

I have a WRT54G router that is set up to serve out addresses via DHCP. It correctly serves up addresses to every other machine on the network, including another PC, my macbook when connected via ...
10
votes
1answer
5k views

Windows clients not using NTP server provided via DHCP

I have a network consisting mostly of Windows Vista and 7 clients and an Ubuntu server. The server provides both the DHCP and NTP services through dhcp3-server and openntpd. In my dhcpd.conf, the ...
8
votes
3answers
865 views

Does a router know not to hand out static IP addresses to other devices?

I set a computer on my network to use a Static IP address Shutdown the computer so its not on and not connected to the network Question: How does my router know not to hand out that IP address to ...
8
votes
4answers
6k views

Obtaining a DHCP IP address if static address is not available

I have seen some questions that are similar to my problem but not a good solution. Ex. User has a laptop and has a static IP address at the office. They also take the laptop off site where they also ...
8
votes
5answers
5k views

IP address alias assigned by DHCP

I would like to create several aliases to eth0, but have the addresses assigned by DHCP instead of being set to static IP's. Is this even possible? All the examples I've seen assign a static IP using ...
7
votes
4answers
2k views

What does static DHCP mean? Static Dynamic is confusing

I've found some home wireless routers/ADSL+ modems (ZyXEL 660) talking about Static DHCP, when refering to assosiating a specific MAC to an IP, but still serve the configuration over DHCP. Doesn't ...
7
votes
2answers
5k views

Unable to resolve .foo.local domain names

My workplace has an intranet with domain names like server01.foo.local, server02.foo.local, etc. I recently booted the Fedora 16 live environment to test it out and discovered that these domain names ...
7
votes
4answers
7k views

How to configure `eth0` to retry `dhclient` when unplugged and replugged?

I'm working on a linux gadget. I want it to get DHCP if I plug in the network cable after it has booted up already or if the network cable unplugged and replugged. One solution is to run a script ...
7
votes
2answers
1k views

WiFi cannot connect to internet in two router setup

I am struggling to setup my home network. I have the following setup, also shown in the diagram below (sorry for the MS Word screenshot!): My landlord has an ADSL connection, established by Router ...
6
votes
8answers
29k views

How can I add additional search domains to the resolv.conf created by dhclient in CentOS

When my CentOS virtual machine boots it uses DHCP to get an IP address. It also overwrites resolv.conf with the DNS settings provided by the DHCP server. The DHCP server doesn't supply any search ...
6
votes
2answers
4k views

What is the “Alternate Configuration” tab in TCP/IP settings

As I know there is two choice for configuring a computer IP address in the network. Assigning a Static IP or obtaining a dynamic IP from a DHCP server. But what is the Alternate Configuration in ...
6
votes
6answers
7k views

Why do most routers not include local DNS?

I need to change my firewall/router, and I'd prefer something with built-in DNS to resolve queries on the local subnets. I've got a mixed Linux/Windows system, often with only one computer turned on, ...
6
votes
4answers
4k views

dhclient and dhcpcd the real difference

I can't figure out the difference from just the man pages. I can see what is a daemon and one is a client, but what does that mean practically when using the commands? Also what is the difference ...
6
votes
10answers
21k views

Why won't a MacBook Pro running Snow Leopard obtain an IP address (DHCP)?

Background: I am trying to connect my MacBook Pro to a business grade network where I do not have access to reboot the server, switches, or router. Problem: The MacBook Pro (running Snow Leopard ...
6
votes
3answers
870 views

Why does my computer not always automatically request a new DHCP lease when switching networks?

I've noticed an interesting problem recently where my laptop will not automatically refresh my DHCP lease when changing between wireless networks. Instead, it will attempt to use the existing lease ...
5
votes
5answers
25k views

How can I tell if my IP is static or assigned by DHCP on Windows 7?

I don't know if my IP is static or assigned by DHCP. How can I find out which it is? I'm running Windows 7.
5
votes
3answers
2k views

How to use dnsmasq with DHCP-assigned DNS servers?

TL;DR version: How do I configure dnsmasq to fall back to the DNS servers pointed to by the DHCP server on my LAN, to enable switching wireless networks? On my developer laptop I've recently started ...
5
votes
7answers
21k views

How to assign a static IP with a linksys WRT54G2?

For all my googleing it appears the best you can do is tell your computer not to use DHCP; I cannot find a way to do this at the Access Point level. EDIT: This is not for port forwarding. This is ...
5
votes
1answer
3k views

Preventing SSH RSA host key warnings for change of key vs IP address

I have a network with DHCP enabled, and also a computer that dual boots operating systems and has different SSH keys on each (and yes, I would like to keep different keys on each rather than copying ...
5
votes
2answers
5k views

What are the common router default DHCP IP address ranges?

I'm trying to find out what the default DHCP ranges are for common routers. Does anyone know?
5
votes
3answers
6k views

Creating WiFi Access point on a single interface in Linux

I am trying to create a WiFi hotspot or an access point on my Linux laptop. I am using Opensuse Kde 12.3. I found out a software called hostapd which lets you create hotspot but it requires two ...
5
votes
2answers
5k views

DD-WRT: DNSMasq expand-hosts not working

I have a Linksys router running DD-WRT (Firmware: DD-WRT v24-sp2 (09/08/09) mini). I have it successfully resolving the DNS names for my DHCP-assigned systems, but only when I fully-qualify those ...
5
votes
2answers
6k views

Accessing a router which isn't a DHCP server

I have a Linksys WRT54GL router with Tomato installed on it. My network configuration requires me to disable the DHCP server on the router. After disabling it, I do not know the IP of the router ...
5
votes
1answer
964 views

Can I add DNS but keep those provided by DHCP in OSX?

I'm trying to add an additional DNS entry in my OSX network preferences but I want to keep the DNS provided by DHCP. These show up in gray, but when I click the plus button below them, they disappear ...
5
votes
3answers
6k views

PXE Boot Server without DHCP, for many different computers?

I work at a helpdesk for a university where it is very common for us to reformat people's computers using XP, Vista, and Win7 CD's and DVD's. Of course, the discs get scratched and lost a lot. It is ...
4
votes
4answers
39k views

How to find my DHCP server IP address via a command prompt in Windows?

Linux has easy commands to find the DHCP server IP address via a command prompt. Is there anything for Windows?
4
votes
8answers
7k views

How can I change my public IP address?

I'm looking for a way to change my public IP address. You know, the one that other websites see. I know what I'm looking for is basically a proxy server, but I don't want to use a proxy for 2 ...
4
votes
3answers
989 views

Network is not connecting after startup automatically in Windows

After some perturbations with network drivers now I have a situation where the network is not connecting automatically after the boot-up. It indicates, that the connection is limited or no ...
4
votes
1answer
137 views

From my 192.168 box, how do i find 10.0 virtual machine on the same box?

I am running Ubuntu 12.04 and Virtual Box 4.1.12. I have created a Debian server under Virtual Box. For reasons I don't understand, DHCP grants my Ubuntu box 192.168.20.50 and my Debian VirtualBox ...
4
votes
6answers
1k views

user friendly name for ip address on home network

How can I set up some sort of local DNS service, so that instead of using ipaddresses to do things like VNC and remote desktop a more URL like thing can be used. All the devices on a network have a ...
4
votes
1answer
5k views

DHCPv6 server + client on Linux

Which IPv6 capable DHCP server and client is best to use on Ubuntu? I can't find a good HOWTO. ISC DHCP?
4
votes
3answers
5k views

How to determine gateway address when going from DHCP to static IP address with Ubuntu

What's the proper way to determine the computer's gateway when going from DHCP to a static IP. Operating system is Mythbunutu with Ububtu desktop installed. I had previously been editing ...
4
votes
3answers
1k views

Self-assigned IP address

I sometimes have problems dropping IP addresses after changing networks and get stuck with a self-assigned IP that I cannot drop by hitting the renew "DHCP Lease" button on my Mac OS X.5 Leopard. The ...
4
votes
3answers
4k views

How could I fix “No subnet declaration for restart (0.0.0.0)”?

I have a DHCP service installed on my distribution, Backtrack 5 R2 (ubuntu 10.04) and it was working fine, but when I began to configure DNS it suddenly stoped working, how can I make it work again?? ...
4
votes
3answers
2k views

Where does “Client Name” come from in the DHCP client table on router?

I have a Cisco router. The firmware webpage has a tab the displays the DHCP client table. As the name suggests it lists all of the DHCP clients on the network. The first column in the table is the ...
4
votes
1answer
6k views

How to run a DHCP server on an ethernet port of a MacBook successfully?

I aim to have an ethernet switch on my MacBook ethernet port from which I will have several Raspberry Pi's connected getting their IP via DHCP, each will have a VNC server running on them for remote ...
4
votes
1answer
4k views

Can't get IP on Windows 7 after extensive troubleshooting

My Windows 7 system is not able to pull an IP from my router's DHCP. This just started a few days ago, and I've done quite a bit of troubleshooting. Here's what I've tried in roughly chronological ...
4
votes
1answer
7k views

Arch Linux: eth0 no carrier - network fails at boot

The problem My computer is connected to a network where dhcp is required. So my network configuration in /etc/rc.conf looks like interface=eth0 address= netmask= broadcast= gateway= My deamons are ...
4
votes
2answers
572 views

how to broadcast a PXE server like Trinity Rescue Kit

I would like to set up a portable PXE server for diagnostic purposes. The issue is that I won't always have access to the DHCP server, or the router itself (sometimes a home router) doesn't have an ...
4
votes
1answer
2k views

Configuring default gateway returned by dhcp server

I have a machine which connects via ethernet to a private LAN, and wireless to a network which provides internet connectivity. The private LAN uses a wireless router to perform DHCP. The problem is ...
4
votes
1answer
431 views

In Windows 8, How do I make a static IP for each network?

I would like to have it so that my computer sets its IP address statically depending on which network that it is connected to. I have 3 Networks that I regularly use and it seems that with Windows I ...
4
votes
2answers
2k views

Wired connection periodically disconnects requires ipconfig /release and /renew to reconnect

I just got back into University and after a day of using the internet I suddenly was unable to visit other webpages even though I was still able to chat. I restarted the computer and the internet ...
4
votes
2answers
806 views

What are the benefits of dynamic leased IP addresses in a home network?

I have a small network at home with a router, a printer, a NAS and 4 PCs. My router allows full DHCP management and I have set my router, NAS and printer to have static IP addresses (reserved fixed ...
3
votes
2answers
1k views

What are ping packets made of?

What exactly are in the packets that are sent via the ping command? I was reading a Wikipedia article about magic numbers and saw this: DHCP packets use a "magic cookie" value of '63 82 53 63' ...
3
votes
2answers
2k views

Possible to ipconfig release/renew for only one nic?

I've got two NICs in my Windows 8 Pro (x64) box each connected to different networks. I would like to release and renew the DHCP lease for just one of the NICs. So far I can't find any way to do it ...