# Nginx 99% cpu if upstream server address is ipv6

**URL:** <https://www.ruby-forum.com/t/nginx-99-cpu-if-upstream-server-address-is-ipv6/208502>\
**Category:** NGINX\
**Created:** [June 20, 2011, 9:50am UTC](https://www.ruby-forum.com/t/nginx-99-cpu-if-upstream-server-address-is-ipv6/208502 "2011-06-20T09:50:30Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![luislavena](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/l/0ea827/32.png) [@luislavena](https://www.ruby-forum.com/u/luislavena)\
**Post date:** [June 20, 2011, 9:50am UTC](https://www.ruby-forum.com/t/nginx-99-cpu-if-upstream-server-address-is-ipv6/208502/1 "2011-06-20T09:50:30Z")

</div>

Hi,  
I’m doing a test for nginx to proxy ipv6 requests,

client(v6)----(v6)nginx(v6)----(v6)www

The nginx CPU is 99%

According to the post in the mailing list, nginx doesn’t support ipv6  
upstream, but  
I think it is better report an error other than 99% cpu if ipv6  
address is used in upstream.

BTW, any plan to support ipv6 upstream?

BR,

DeltaY

---

<div class="post-metadata">

**Author:** ![Delta\_Y](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/f9ae1b/32.png) [@Delta\_Y](https://www.ruby-forum.com/u/Delta_Y)\
**Post date:** [January 14, 2012, 2:53pm UTC](https://www.ruby-forum.com/t/nginx-99-cpu-if-upstream-server-address-is-ipv6/208502/2 "2012-01-14T14:53:42Z")

</div>

Hi,  
i have the same problem. any new solutions ?

Regards, Eric

My Setup is:

WORLD → ( nginx ipv4 blancer ) → ( 3 ipv4 webserver )  
WORLD → ( nginx ipv6 blancer ) → ( 3 ipv6 webserver )

My Config is:  
upstream lb4 {  
server XXX.XXX.XXX.XXX:80;  
server XXX.XXX.XXX.XXX:80;  
server XXX.XXX.XXX.XXX:80;  
}  
upstream lb6 {  
server [xxxx:xxxx:xxxx::xxxx]:80;  
server [xxxx:xxxx:xxxx::xxxx]:80;  
server [xxxx:xxxx:xxxx::xxxx]:80;  
}  
server {  
listen 80; ## listen for ipv4  
server\_name lb.netsyn.eu;

```
access_log /var/log/nginx/xxx.xxx.eu.access.log;

location / {
        proxy_pass http://lb4;
        proxy_redirect off;
        proxy_next_upstream error timeout invalid_header

```

http\_500;  
proxy\_connect\_timeout 2;  
proxy\_set\_header Host $host;  
proxy\_set\_header X-Real-IP $remote\_addr;  
proxy\_set\_header X-Forwarded-For  
$proxy\_add\_x\_forwarded\_for;  
}  
}

server {  
listen [::]:80 default ipv6only=on; ## listen for ipv6  
server\_name lb.netsyn.eu;

```
access_log /var/log/nginx/xxx.xxxx.eu.access.log;

location / {
        proxy_pass http://lb6;
        proxy_redirect off;
        proxy_next_upstream error timeout invalid_header

```

http\_500;  
proxy\_connect\_timeout 2;  
proxy\_set\_header Host $host;  
proxy\_set\_header X-Real-IP $remote\_addr;  
proxy\_set\_header X-Forwarded-For  
$proxy\_add\_x\_forwarded\_for;  
}  
}

Posted at Nginx Forum:

> **[Re: nginx 99% cpu if upstream server address is ipv6](https://forum.nginx.org/read.php?2,208399,221226#msg-221226)**
>
> Hi, I'm doing a test for nginx to proxy ipv6 requests, client(v6)----(v6)nginx(v6)----(v6)www The nginx CPU is 99% According to the post in the mailing list, nginx doesn't support ipv6 upstream, but I think it is better report an error othe