Nginx prematurely closing connections when reloaded

[Maxim Dounin]

Hello!

On Tue, Mar 26, 2024 at 03:03:19PM +0100, Sébastien Rebecchi wrote:

> I finally decided to activate retries of non idempotent requests, cause I
> already manage data deduplication.
> 
> Now I have: proxy_next_upstream error timeout invalid_header http_502
> http_504 non_idempotent;
> 
> Nevertheless I still see the same error messages when I trigger a reload of
> an nginx in upstream.
> Does it mean the problem is that same, or just that nginx (the ones in
> front) still displays such error messages for information, but has
> effectively retried the request on another server in upstream?

The latter.  As the errors are still here, such error messages are 
expected to appear in logs.  The difference is that corresponding 
POST requests will be automatically retried to other upstream 
servers, so clients will get proper upstream responses instead of 
502.  Looking into corresponding access log entries should show 
the difference, especially if $upstream_status is logged 
(http://freenginx.org/r/$upstream_status).

-- 
Maxim Dounin
http://mdounin.ru/