fail_timeout in upstream not rescpeted?

[plrunner]

Hi everybody,

I am running nginx v1.11 and I noticed something pretty weird in my
error.log.

I have fail_timeout=1800s along with max_fails=1 in my upstream and
proxy_next_upstream is set to "error timeout", so I expect an upstream host
to be taken off the list for 30 minutes just after the first failed
connection.

Here is what I unexpectedly get in the error.log

2017/01/23 09:49:48 [error] 30676#30676: *2202666 connect() failed (111:
Connection refused) while connecting to upstream, client: 93.XX.YYY.228,
server: *.foobar.com, request: "GET /generic/api/v1/tag/1006 HTTP/2.0",
upstream: "http://[beaf:beaf:1001:a001::003D:4]:8080/generic/api/v1/tag/1006
host: "cy1.foobar.com", referrer: "https://web.foobar.com/"
2017/01/23 09:49:48 [warn] 30676#30676: *2202666 upstream server temporarily
disabled while connecting to upstream, client: 93.XX.YYY.228, server:
*.foobar.com, request: "GET /generic/api/v1/tag/1006 HTTP/2.0", upstream:
"http://[beaf:beaf:1001:a001::003D:4]:8080/generic/api/v1/tag/1006 host:
"cy1.foobar.com", referrer: "https://web.foobar.com/"
2017/01/23 09:57:53 [error] 30695#30695: *2205681 connect() failed (111:
Connection refused) while connecting to upstream, client: 93.XX.YYY.228,
server: *.foobar.com, request: "GET /generic/api/v1/tag/1006 HTTP/2.0",
upstream: "http://[beaf:beaf:1001:a001::003D:4]:8080/generic/api/v1/tag/1006
host: "cy1.foobar.com", referrer: "https://web.foobar.com/"
2017/01/23 09:57:53 [warn] 30695#30695: *2205681 upstream server temporarily
disabled while connecting to upstream, client: 93.XX.YYY.228, server:
*.foobar.com, request: "GET /generic/api/v1/tag/1006 HTTP/2.0", upstream:
"http://[beaf:beaf:1001:a001::003D:4]:8080/generic/api/v1/tag/1006 host:
"cy1.foobar.com", referrer: "https://web.foobar.com/"

The host is reused after just 8 minutes, instead of 30 minutes.

Is there anything wrong in my conf or something I forgot to take into
account?

Thanks for any help here.
Paolo

Posted at Nginx Forum: https://forum.nginx.org/read.php?2,272189,272189#msg-272189