nginx error (connect() failed, 61 "Connection refused", but everything works)

[Sergey Kandaurov]

> On 15 Aug 2018, at 13:02, Gerben Wierda <gerben.wierda at rna.nl> wrote:

[..]

> But nginx reports (apparently once per session):
>    2018/08/15 11:34:48 [error] 242#0: *881 kevent() reported that connect() failed (61: Connection refused) while connecting to upstream, client: 192.168.2.67, server: MYHOST, request: “GET /gerbentest/?delimiter=%2F&max-keys=1000&prefix=duplicati-ifdb6b7ac174b4e5094b04e7321d10c6b.dindex.zip.aes HTTP/1.1”, upstream: “http://[::1]:9003/gerbentest/?delimiter=%2F&max-keys=1000&prefix=duplicati-ifdb6b7ac174b4e5094b04e7321d10c6b.dindex.zip.aes”, host: “MYHOST:9000”

Note [::1]:9003 in upstream, which is likely the address nobody listens.

> I’d like to find out why this happens. Can someone help me find the cause of these errors? The config for the minio servers is:
> 
> server {
>     listen              9000 ssl;
>     server_name         MYHOST;
>     ssl_certificate     minio_certificate_chained.crt;
>     ssl_certificate_key minio_certificate.key;
>     ssl_protocols       TLSv1.2;
>     proxy_buffering     off;
>     client_max_body_size 1000m;
>     location / {
>         proxy_set_header Host $http_host;
>         if ($http_authorization ~* "^AWS4-HMAC-SHA256 Credential=REMOVED") {
>             proxy_pass http://localhost:9001;
>         }

If a domain name resolves to several addresses,
which is apparently the case for "localhost",
all of them will be used in a round-robin fashion.

See for details:
http://nginx.org/r/proxy_pass

-- 
Sergey Kandaurov