DNS problem

Server NGINX
1

I know nginx 1.7.4 fixes a bug about DNS resolver, but i do not quite
understand why this would lead to a request hang, Because there is a
timeout handling, at a specified time if there is no response the
timeout
callback will be called，so why here can lead to request hang，

Could someone show me a example about how lead to request hang?

I ask this,because i recently encountered a problem online product(it
use
nginx-1.7.2), may be caused by this problem

2

On Sun, Aug 17, 2014 at 02:37:46PM +0800, ywsample wrote:

I know nginx 1.7.4 fixes a bug about DNS resolver, but i do not quite
understand why this would lead to a request hang, Because there is a
timeout handling, at a specified time if there is no response the timeout
callback will be called，so why here can lead to request hang，

Could someone show me a example about how lead to request hang?

The requests would hang for 30 seconds instead of retrying a
DNS query periodically.

See proxied requests hang when DNS response has wrong ident
for details.