Finishing Dnsmasq

Error at the logs: DHCP packet received on eth0.2 which has no address.

Checked logs Asus RT-N16 OpenWRT and found out the warning that repeats constantly (internet connection using PPPoE):

Thu Jul 3 18:54:52 2014 daemon.warn dnsmasq-dhcp[1381]: DHCP packet received on eth0.2 which has no address

The solution is in the file /etc/dnsmasq.conf which manages DNS and DHCP services at OpenWRT

It needs to isolate PPPoE interface from the DHCP “give-outs”  :

# Do not interact to WAN interface(eth0:2)
except-interface=eth0.2

Big fight with DHCPINFORM at dnsmasq service

In some circumstances OpenWrt (and other Linux-OS) using dnsmasq DHCP-service, you can find some flood-messages DHCPINFORM in system log:

May 16 15:01:20 OpenWrt daemon.info dnsmasq-dhcp[2451]: DHCPINFORM(br-lan) 172.16.10.30 90:e6:ba:dc:2e:c3

May 16 15:01:20 OpenWrt daemon.info dnsmasq-dhcp[2451]: DHCPACK(br-lan) 172.16.10.30 90:e6:ba:dc:2e:c3 avalanche

It is happening because DHCP-client of Windows 7 (along with some other Microsoft masterpieces) obssesed to receive proxy-server settings from DHCP-server, and it is going on and on and on and on even when DHCP-server does not have these settings at all. Default dnsmasq configuration does not send any proxy-server information, but Windows-OS keep asking for them again and again… and again.

You can force it to shut the f… up my friend by adding the following option to the file /etc/dnsmasq.conf:

# There is no PROXY(for Win OS'es), stop asking!
 dhcp-option=252,"\n"

This option is just screaming over to Windows operating systems that “THERE IS NO FREAKEN PROXY HERE STUPID M…F…, STOP ASKING!