WRote a small script in php to check your D3's and reboot them automatically in case an hashboard has errors
https://gist.github.com/tperalta82/6e11253cd4b9cf9c5c6fa15bbf046d4fput this in a linux server as a cronjob, change the $hosts array, to add your hosts.
There are 3 different methods to call reboot on the miner, personally, the wget one is better for me, because it runs everywhere (embedded devices)
Had an issue with curl, seems to fail to authetnicate on some weird cases
and ssh lib is not present everywhere.
Read the code first, understand it, redistribute it, improve it, do whatever you want with it.
P.S.: it works for me