Using supervisord for Nginx+FastCGI+PHP

Posted: Jun 23, 2010 - Modified: Jun 22, 2010| geek, linux

I was having problems with spawn-fcgi-standalone occasionally resulting in dead PHP processes, which caused 502 Bad Gateway errors on my site. Crontabbing an /etc/init.d/init-fastcgi start didn't help much, so I looked for other ways to do it. Supervisord looked promising.

Here’s how to get Supervisord:

apt-get install python-setuptools
easy_install supervisor

Here’s what to add to /etc/supervisord.conf:

[fcgi-program:php5-cgi]
socket=tcp://127.0.0.1:9000
command=/usr/bin/php5-cgi
numprocs=5
priority=999
process_name=%(program_name)s_%(process_num)02d
user=www-data
autorestart=true
autostart=true
startsecs=1
startretries=3
stopsignal=QUIT
stopwaitsecs=10
redirect_stderr=true
stdout_logfile=/var/log/php5-cgi.log
stdout_logfile_maxbytes=10MB

So far, so good. When I kill the php process, supervisord starts it back up. Progress!

supervisord doesn’t come with an init.d script, but you can get one for Ubuntu.

You can view 8 comments or e-mail me at sacha@sachachua.com.

8 comments

doddy

2010-06-23T16:35:23Z

But...what is the root of the problem? Why is PHP dying? Can you sleep at night without knowing this?

Sacha Chua

2010-06-23T17:20:58Z

I came across some webpages that suggested php-fcgi wasn't the most reliable way to do it (long pages would die, etc.), and that fpm or supervisord might be better. This way, I can keep the extraneous bad gateway errors from my error logs, and focus on what's causing the occasional process to die.

perusio

2010-09-22T06:53:25Z

Have you heard of Monit? I use for supervising both nginx and php-cgi. It's written in C and not in Python. http://mmonit.com

I've published by monit configuration for supervising MariaDB (MySQL), nginx, and php-cgi, among other things on github: http://github.com/perusio/m... just in case you're interested in checking out monit.

Sacha Chua

2010-09-23T17:07:47Z

Thanks for sharing!

warren

2010-10-07T06:13:13Z

Supervisord has been great to work with. However, sometimes it seems to not want to log to the specified stdout_logfile . Even tho there is absolutely std out.

Have you ever had issues with supervisord logging to stdout_logfile ?

Divyesh Ramani

2010-11-03T00:59:26Z

Thanks. very helpful.. Finally configured it for my blog with auto start. No worries about crashing php5-cgi process.

Juan

2011-01-29T06:43:15Z

@warren: Yeah! i'm seeing the same thing. Ever figure it out?

warren

2011-01-29T23:03:24Z

Yea, supervisord only logs in bursts when there is enough data for the particular process. In my case it was only writing when there was ~1K worth of data (and it was a timed job, so it appeared to be related to time - but that was not the case).

I have also seen some strange behavior with the log rotation. For example, if you are logging to test.log, sometimes you will find it is logging to test.log.5

A ls -lart helps with that :)

All things considered, supervisord has been doing a great job. We have been using it in production for a couple months.