How do i make ubuntu request a specific ip address from a dhcp server?

Question

So here's the deal. My router assigns ip addresses starting from 192.168.0.50. I have a couple of computers running ubuntu which i want the router to assign 192.168.0.50 and 192.168.0.51 every time they request for an ip address. Any ideas? Thanks in advance.:)

Solution 1

You have a few options.

1) DHCP reservations on your router. Some routers have this look around in the settings.

2) I'm pretty sure if you go to networking manager you can set a manual ip, but still be on DHCP. I mostly use cli.

3) Set a staic ip with this guide http://www.howtogeek.com/howto/ubuntu/change-ubuntu-server-from-dhcp-to-a-static-ip-address/

Solution 2

using the linux program dhclient.

If you don't have linux installed, you can use a bootable Linux live CD.

[edit] If you do this trick to create an address reservation for an actual Windows machine, first switch the NIC in Windows to a static IP, because after a reboot in DHCP mode Windows may send a DHCP request with its last used IP, which would annihilate your efforts with dhclient below...

The trick is to send a DHCP request with your desired IP address from the same NIC (or better: same MAC address).

Edit the /etc/dhcp/dhclient.conf and add the following line (you might have to first copy the file to a writeable location if booting from a CD):

send dhcp-requested-address 192.168.1.240;

Then stop and start dhclient as user root, where your NIC is eth0 (check by issuing ip addr show beforehand)

dhclient -r -v
dhclient -4 -d -v -cf /etc/dhcp/dhclient.conf eth0

If successfull, your DHCP server will fulfill your prepared request. Sometimes you will have to delete the device entry in the DHCP table before issuing dhclient -4 -d ....

Then make that device IP address in the DHCP table of the router a fix address reservation. This will associate the IP to the MAC of the device and return the same IP everytime a DHCP request with that MAC address is encountered in the future.

Source

Solution 3

The simplest thing to do is to set computer A to a static IP of 192.168.0.50 and computer B to a static IP of 192.168.0.51 and configure your router to send DHCP addresses starting at 192.168.0.52 instead of 192.168.0.50. You may also wish to reserve addresses as outlined by wlraider70

Comments

[GypsyCosmonaut]

-1 for plagiarism superuser.com/a/487608/629507 , you could have mentioned the link in the comment