Since update to 3.6 lighttpd often goes to permanent dropped connection state.
Investigating the logs shows:
2017-03-10 22:34:17: (connections-glue.c.291) connection closed - read failed: Function not implemented 38
once for every connection attempt.
Restarting lighttpd with
/etc/init.d/lighttpd restart
honored with
2017-03-11 07:02:50: (server.c.1295) WARNING: unknown config-key: setenv.set-environment (ignored)
But solves the problem for a while.
Later on it will stuck again and have to be restarted again…