I'm just testing a Raspberry Pi 3 and nginx / PHP7 / APC-Cache for TYPO3 8, most of the time it works fine, but sometimes I get the error "bad gateway" 502.
Has anyone tips / infos for me? I believe it is the nginx "sites-available" settings or caching.
Error.log
recv() failed (104: Connection reset by peer) while reading response header from upstream
