Re: Nginx-Upstream-proxy next upstream-惊天大Bug

[Maxim Dounin]

Hello!

On Thu, May 31, 2012 at 10:55:11AM -0400, youzhengchuan wrote:

> upstream backend {
>      server flvdownload.ppserver.org.cn:80 max_fails=0;
>      server flvstorage.ppserver.org.cn:80 backup;
> }
> 
> server{
>   ....
>   location / {
>     proxy_next_upstream error timeout invalid_header http_500 http_502
> http_503 http_504;
>     proxy_pass http://backend;
>   }
> }
> 
> #----------------------------------------------------------------------------------------
> 
> 当upstream中backup域名“
> flvstorage.ppserver.org.cn”解析结果为2个IP时候，“flvdownload.ppserver.org.cn”如果返回有异常可以成功proxy_pass到backup。
> But：当upstream中backup域名“
> flvstorage.ppserver.org.cn”解析结果为1个IP时候，backup无法使用，nginx会不断的请求“flvdownload.ppserver.org.cn”。
> 
> 屡试不爽，就是不知道这是一个Bug吗？

As far as I understand, you are hitting another variant of this bug:

http://trac.nginx.org/nginx/ticket/47

It usually manifests itself with "proxy_next_upstream http_404", 
but max_fails=0 does essentially the same.  The bug is fixed in 
1.3.0.

Maxim Dounin

p.s. This is English mailing list, please don't write in Chinese 
here.  Thank you.