Restarting upstream servers

Server NGINX
1

Hi,

I’m using a bunch of upstream servers and using nginx as a proxy for
them. The upstreams run on two different machines.

When I restart the upstreams on one server, I get a bunch of errors like
these:

2008/05/21 18:02:39 [error] 4658#0: *36236 sendfilev() failed (134:
Transport endpoint is not connected) while sending request to
upstream, client: 209.191.207.182, server: domain.com, URL:
“/feed/products?t=1211418157562”, upstream:
“http://10.12.32.192:3021/feed/products?t=1211418157562”, host:
“domain.com”

2008/05/21 18:02:40 [error] 4645#0: *66641 connect() failed (146:
Connection refused) while connecting to upstream, client:
136.182.158.129, server: domain.com, URL:
“/uploaded_files/0025/1630/Springboard_midget_size.jpg?1208317017”,
upstream:
“http://10.12.32.84:3021/uploaded_files/0025/1630/Springboard_midget_size.jpg?1208317017”,
host: “static2.domain.com”, referrer:
“http://domain.com/puzzles/2110-5-21-2008”

Any way to avoid those? Ideally, since not all the upstreams are
down, when the request to the upstream fails due to connection
problems, I’d like to try the request on a different upstream, so the
user doesn’t see anything wrong.

Joe

2

That happens automatically

3

I understand you want to prevent the first set of failed request
against the restarting upstreams.

Ugly but it should work:

Modify Nginx configuration, remove the upstream for the first server,
signal it.
Restart upstream servers in the first server.
Modify Nginx configuration, add the restarted upstreams and remove the
the ones from the second, signal it.
Restart upstream servers in the second server.

Nginx reloads configuration very quickly.

All this can be easily automated.

–
Aníbal Rojas

http://anibal.rojas.com

4

That makes perfect sense, thanks!

5

Please let us know how it works.