Upstream host name or address

Server NGINX
#1

hi,
is it possible to find upstream host which serves as proxy for a
connection;
i know that $upstream_addr is the key ; but i need to set the address
with set_proxy_headdr as host
but $upstream_addr return address and port together

upstream test
{
ip_hash;
192.168.1.1;
192.168.1.2;
}

location /
{
proxy_set_header Host $upstream_addr; ---------> fail cause it set for
example 192.168.1.1:80 but i need 192.168.1.1
proxy_pass http://test;
}

any suggestion ?

thank you in advance…

Posted at Nginx Forum:
http://forum.nginx.org/read.php?2,208188,208188#msg-208188

#2

i forgot to add server in above upstream samples;;but my main config is
correct;
i just wanted to show an example of what i wanna do…
upstream test
{
ip_hash;
server 192.168.1.1;
server 192.168.1.2;
}

thanks again;
i hope someone help me…

Posted at Nginx Forum:
http://forum.nginx.org/read.php?2,208188,208192#msg-208192

#3

Hello!

On Sun, Jun 19, 2011 at 07:26:58AM -0400, torajx wrote:

192.168.1.1;

any suggestion ?

Request is created only once and you can’t set different headers
when working with different servers in upstream. Servers in
upstream block must accept identical requests.

(Moreover, $upstream_addr isn’t an address of upstream server nginx is
talking to, but a list of servers nginx have talked to during
handling of a request. And usually it won’t contain anything
while creating request to upstream.)

If you really need different requests to different backend servers
you’ll have to use different proxy_pass’es for that (or use
variables). E.g. in 0.9.6+ you may do something like this:

map $remote_addr $backend {
    default          "should not happen";
    ~[02468]\.\d+$   192.168.1.1;
    ~[13579]\.\d+$   192.168.1.2;
}

location / {
    proxy_pass http://$backend;
}

(no need for proxy_set_header here, as $proxy_host will resolve to
the backend’s ip address and default “proxy_set_header Host
$proxy_host;” will do what you want)

But note that recommended aproach is to actually configure
identical backend hosts, not adapt requests for each one.

Maxim D.

#4

by the way nx.chare.ir in my nginx server and i forgot to remove real
name at the end…no problem :wink:
it means users can type nx.chare.ir/csupdate
and in csupdate there is some link to images that i mention in images
location…

Posted at Nginx Forum:
http://forum.nginx.org/read.php?2,208188,208380#msg-208380

#5

sorry againa and again
i forgot one line again i have this line in my csupdate location too’
proxy_redirect http://192.168.1.1/csupdate
http://nx.chare.ir/csupdate;

my csupdate location is like this finally :

location /csupdate {
proxy_pass http://mysites_hash/csupdate;
proxy_set_header Host 192.168.1.1;
proxy_redirect http://192.168.1.1/csupdate
http://nx.chare.ir/csupdate;
}

but this works when i have only one server in mysites_has upstream

Posted at Nginx Forum:
http://forum.nginx.org/read.php?2,208188,208391#msg-208391

#6

hi again and thank you fo reply
this is my main config file; sorry i remove real ip address and site
names

upstream mysites {
server 192.168.1.1 weight=5;

server 192.168.1.2 weight=3;

}
upstream mysites_hash {
ip_hash; #base on clinet ip address and can not use weight;
server 192.168.1.1;

server 192.168.1.2;

}
upstream myimages {
server images.mysite.com;
}
server {
listen 80;
server_name nx.chare.ir;
set $tmp tempstr;
access_log var/log/nx_csupdate_access.log main;
log_format main “$upstream_addr”;

   location /  {
         deny all;
   }
   location /csupdate/images {
         proxy_pass      http://myimages;
   }
   location /csupdate {
      proxy_pass      http://mysites_hash;
      proxy_set_header Host    192.168.1.1;
   }

as you can see i commented my 2th server in my upstream;
the proxy_set_header line in location /csupdate was the only soloution
that solved
my problem; because my servers (192.168.1.1, 2) will redirect users base
on some condition
and without proxy_set_header line the browsers fall in endless loop and
retun errors;

for $upstream_addr in can see 192.168.1.1:80 in my log files as i
formated simply likme above;
but what is soloution in i want to use 192.168.1.2 server too ??

thank you in advance

Posted at Nginx Forum:
http://forum.nginx.org/read.php?2,208188,208379#msg-208379