nginx 502 bad gateway - fastcgi not listening? (Debian 5)
- by Sean
I have experience with nginx but it's always been pre-installed for me (via VPS.net pre-configured image). I really like what it does for me, and now I'm trying to install it on my own server with apt-get. This is a fairly fresh Debian 5 install. I have few extra packages installed but they're all .deb's, no manual compiling or anything crazy going on.
Apache is already installed but I disabled it. I did apt-get install nginx and that worked fine. Changed the config around a bit for my needs, although the same problem I'm about to describe happens even with the default config.
It took me a while to figure out that the default debian package for nginx doesn't spawn fastcgi processes automatically. That's pretty lame, but I figured out how to do that with this script, which I found posted on many different web sites:
#!/bin/bash
## ABSOLUTE path to the PHP binary
PHPFCGI="/usr/bin/php5-cgi"
## tcp-port to bind on
FCGIPORT="9000"
## IP to bind on
FCGIADDR="127.0.0.1"
## number of PHP children to spawn
PHP_FCGI_CHILDREN=10
## number of request before php-process will be restarted
PHP_FCGI_MAX_REQUESTS=1000
# allowed environment variables sperated by spaces
ALLOWED_ENV="ORACLE_HOME PATH USER"
## if this script is run as root switch to the following user
USERID=www-data
################## no config below this line
if test x$PHP_FCGI_CHILDREN = x; then
PHP_FCGI_CHILDREN=5
fi
ALLOWED_ENV="$ALLOWED_ENV PHP_FCGI_CHILDREN"
ALLOWED_ENV="$ALLOWED_ENV PHP_FCGI_MAX_REQUESTS"
ALLOWED_ENV="$ALLOWED_ENV FCGI_WEB_SERVER_ADDRS"
if test x$UID = x0; then
EX="/bin/su -m -c \"$PHPFCGI -q -b $FCGIADDR:$FCGIPORT\" $USERID"
else
EX="$PHPFCGI -b $FCGIADDR:$FCGIPORT"
fi
echo $EX
# copy the allowed environment variables
E=
for i in $ALLOWED_ENV; do
E="$E $i=${!i}"
done
# clean environment and set up a new one
nohup env - $E sh -c "$EX" &> /dev/null &
When I do a "ps -A | grep php5-cgi", I see the 10 processes running, that should be ready to listen.
But when I try to view a web page via nginx, I just get a 502 bad gateway error.
After futzing around a bit, I tried telneting to 127.0.0.1 9000 (fastcgi is listening on port 9000, and nginx is configured to talk to that port), but it just immediately closes the connection.
This makes me think the problem is with fastcgi, but I'm not sure what I can do to test it. It may just be closing the connection because it's not getting fed any data to process, but it closes immediately so that makes me think otherwise.
So... any advice? I can't figure it out. It doesn't help that it's 1AM, but I'm going crazy here!
