# Backup resolver possible?

**URL:** <https://www.ruby-forum.com/t/backup-resolver-possible/222277>\
**Category:** NGINX\
**Created:** [August 21, 2012, 8:04am UTC](https://www.ruby-forum.com/t/backup-resolver-possible/222277 "2012-08-21T08:04:39Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![aris](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/258eb7/32.png) [@aris](https://www.ruby-forum.com/u/aris)\
**Post date:** [August 21, 2012, 8:04am UTC](https://www.ruby-forum.com/t/backup-resolver-possible/222277/1 "2012-08-21T08:04:39Z")

</div>

version: nginx 1.2.0 on centos 5.5 64bit

Nginx works as a http proxy. There are two resolver: ip1 and ip2.  
When ip1 fails on some url, nginx gives 502 error, but ip2 works on the  
url.

Can multi-resolver be used as master-slave? nginx may try slave resolver  
when master resolver fails.

worker\_processes 1;  
error\_log /dev/null crit;  
worker\_rlimit\_nofile 65535;  
events  
{  
use epoll;  
worker\_connections 65535;  
}

http  
{  
charset off;  
override\_charset off;  
proxy\_buffering off;  
gzip off;  
access\_log off;  
resolver ip1,ip2;  
proxy\_buffer\_size 64k;  
proxy\_buffers 4 64k;  
server  
{  
listen 1002;  
location /  
{  
proxy\_set\_header Host $host;  
proxy\_set\_header Accept-Encoding “”;  
proxy\_pass http://$http\_host$request\_uri;  
}  
}  
}

Posted at Nginx Forum:

> **[backup resolver possible?](https://forum.nginx.org/read.php?2,229938,229938#msg-229938)**
>
> version: nginx 1.2.0 on centos 5.5 64bit Nginx works as a http proxy. There are two resolver: ip1 and ip2. When ip1 fails on some url, nginx gives 502 error, but ip2 works on the url. Can multi-resolver be used as master-slave? nginx may try slave...