I’ve been able to identify this as an nginx issue.
{“log”:“2020/03/23 12:51:22 [error] 133#0: *23 upstream timed out (110: Connection timed out) while reading response header from upstream, client: 172.16.172.31, server: _, request: "GET /websocket/ HTTP/1.1", upstream: "http://127.0.0.1:8051/websocket/\”, host: "172.16.175.197"\n",“stream”:“stderr”,“time”:“2020-03-23T12:51:22.684174535Z”}
{“log”:“172.16.172.31 - - [23/Mar/2020:12:51:22 +0000] "GET /websocket/ HTTP/1.1" 504 578 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.149 Safari/537.36" "-"\n”,“stream”:“stdout”,“time”:“2020-03-23T12:51:22.684298239Z”}