nginx abort connection during reload when proxy_cache enabled

[Maxim Dounin]

Hello!

On Thu, Jun 23, 2022 at 07:47:09PM +0800, Wenjun wrote:

> We use nginx as the cluster ingress provider, and hit the case 
> when:
>  1. enabled proxy_cache, and the specific cache is expired
>  2. nginx is reloading config
> then for incoming request, the backend servers can still receive 
> the request and send back response to nginx, while client will 
> receive "curl: (52) Empty reply from server".
> 
> 
> It seems nginx reload may cause the connection break?
> 
> 
> attached debug log below:

>From the debug log it looks like an issue with "aio_write", as 
documented here:

https://trac.nginx.org/nginx/ticket/2162

Switching off "aio_write" should fix this if this issue manifests 
itself in your particular setup.

Note that you are writing to the mailing list dedicated to nginx 
development.  Unless you are willing to submit patches, please 
avoid further user-level posts here.  If you have additional 
questions, please use the nginx@ mailing list instead.  Thank you.

Note well that posting logs as images might not be a good idea.  
Posting plain text logs is generally a much better idea.  Thank 
you again.

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