Stop DHCP INFORM flooding
Revision as of 15:58, 8 July 2012 by Morgan Lindqvist (talk | contribs)
Background
Windows 7 among others ask for proxy settings using DHCP. The issue is that they do not stop asking until they have received an answer. This results in that the log contains a lot information about these requests, an example can be found below.
Jul 1 06:34:09 MorganB3 dnsmasq-dhcp[1638]: DHCPINFORM(br0) 10.69.10.59 00:23:14:c5:33:fc Jul 1 06:34:09 MorganB3 dnsmasq-dhcp[1638]: DHCPACK(br0) 10.69.10.59 00:23:14:c5:33:fc MorgansVaioF12Z
This wiki entry describes how to modify the B3 to stop this traffic.
Configuration
No specific configuration information is needed
Packages
No new packages is needed
Setup
Login to the B3 and become the root user
su
Go the the dnsmasq config directory and create a new file
cd /etc/dnsmasq.d touch no_proxy.conf
Add the following text into the file
# This will tell DHCP clients to not ask for proxy information # Some clients, like Windows 7, will constantly ask if not told NO dhcp-option=252,"\n"
Restart DNS
We are now completed so let us restart the server
/etc/init.d/dnsmasq restart
Test
Look at the log, you should only see one more DHCPINFORM entry per computer connected to the B3, then they should stop asking for proxy information.
tail -f /var/log/daemon.log