I follow those instructions, but in the end " http://connectivitycheck.gstatic.com/generate_204/" page is not responding. so something wrong for me somewhere or i missed something. i am newbie for linux so more simple instruction appreciated with latest software.
# Add user chosen options held in external file
include_shell "cat external.conf 2>/dev/null"
some thing is missing at external.conf. i install php & able to access testing php html page. so that portion is working but this external.conf is not working.