502 Gateway má nginx / 1. 6.2

Estou a receber este erro no nosso servidor privado berkshelf e isto é o que tenho nos registos.

2017/05/15 04:58:07 [error] 1571#0: *312936 connect() failed (111: Connection refused) while connecting to upstream, client: 10.75.1.169, server: radberks.datacenter.radiangroupinc.net, request: "GET /universe HTTP/1.1", upstream: "http://127.0.0.1:26200/universe", host: "radberks"
2017/05/15 04:58:34 [error] 1571#0: *312951 connect() failed (111: Connection refused) while connecting to upstream, client: 10.75.1.169, server: radberks.datacenter.radiangroupinc.net, request: "GET /universe HTTP/1.1", upstream: "http://127.0.0.1:26200/universe", host: "radberks"
2017/05/15 08:57:04 [err
~
Aqui está o meu ficheiro conf.
# cat nginx.conf user nginx; worker_processes 4; error_log /var/log/nginx/error.log; pid /var/run/nginx.pid; events { worker_connections 1024; } http { include /etc/nginx/mime.types; default_type application/octet-stream; access_log /var/log/nginx/access.log; sendfile on; tcp_nopush on; tcp_nodelay on; keepalive_requests 100; keepalive_timeout 65;
Author: BSMP, 2017-05-15