full of … these

Odd DHCP issue

Posted: February 14th, 2009 | Author: | Filed under: howto, idiots, linux | Tags: , , , , | No Comments »

Let’s assume you have a network with a dhcp service (on linux) distributing IPs for your computers.
Suddenly, nobody gets IP from the DHCP.
Probably, you’ll check logs to see whats wrong.
In the logs everything looks normal, except the high number of requests from every computer using dhcp in the network.

dhcpd: DHCPDISCOVER from 00:00:00:00:00:00 via eth0
dhcpd: DHCPOFFER on 192.168.x.x to 00:00:00:00:00:00 via eth0
dhcpd: DHCPREQUEST
dhcpd: DHCPACK

Static IP computers are working as expected.

The next thing you should do is to start wireshark or tcpdump (or any similar application).
Check for errors and odd messages.
In my case it was a second dhcpd service running for the same subnet on another server.

🙂


DHCP sevices for Windows

Posted: February 12th, 2009 | Author: | Filed under: howto | Tags: , , , , | No Comments »

These days I had to install a DHCP service for an isolated network with Windows XP on computers.
I need it to statically associate the MAC addresses of some devices with the same IPs every time the devices are started up.
(IT scientists are lazy and do not to manually configure networking on the devices :))

After 10-20 minutes of search I have found these two wonderful solutions:
Tiny DHCP Server

Goods: easy to use,  GUI, associate MAC with IP at a click away, light
Bads: not so free as I thought

DHCP Server DNS Server

Goods: free, stable, light
Bads: old school text config to associate MACs with IPs

Enjoy