pfSense

In DHCP config screen, add an "Additional DHCP" numbered option, then delete it so you have no more numbered options left. From this point forward any changes to DHCP will generate a php error on an unset on line 312.

diff below:

1. diff services_dhcp.php services_dhcp.php.sav
   312,313c312
   < if ( isset($config['dhcpd'][$if]['numberoptions']['item']))
   < unset($config['dhcpd'][$if]['numberoptions']['item']);
   ---

unset($config['dhcpd'][$if]['numberoptions']['item']);