Summary: Unable to run any of the most simple “Hello World” FastCGI script, any request always terminating into a time out. Seems there is no communication at all between the server and the FastCGI scripts (using dynamic FastCGI scripts).
The environment
- Ubuntu Precise (12.04)
- Package
apache2.2-bin - Package
apache2-mpm-prefork - Package
libapache2-mod-fastcgi - Package
libfcgi-perl - Package
python-flup - Multiple sites configured as virtual hosts on
127.0.0.1 - There exists a
/var/lib/apache2/fastcgidirectory, owned bywww-data, readable by all (owner, group and others) - There exists a
/var/lib/apache2/fastcgi/dynamicdirectory, owned bywww-data, which is restricted to the owner (readable, writable and accessible bywww-dataonly) - There exists an inode/socket file in the
/var/lib/apache2/fastcgi/directory
The FastCGI relevant configurations:
The directory /etc/apache2/mods-enabled/ holds a reference to fastcgi.conf and fastcgi.load (mod_fastcgi is enabled).
The file fastcgi.conf contains the following (left untouched, I did not edit it):
<IfModule mod_fastcgi.c>
AddHandler fastcgi-script .fcgi
#FastCgiWrapper /usr/lib/apache2/suexec
FastCgiIpcDir /var/lib/apache2/fastcgi
</IfModule>
The relevant configuration file in /etc/apache2/sites-enabled/ contains the following (there is nothing more anywhere else about FastCGI specific configuration):
<DirectoryMatch /fcgi-bin>
Options +ExecCGI
<FilesMatch "^[^\.]+$">
SetHandler fastcgi-script
</FilesMatch>
</DirectoryMatch>
The test materials on the test virtual host:
There exist a fcgi-bin/test-perl.fcgi whose content is (the file is executable by all, and readable by owner and group):
#!/usr/bin/perl
use CGI::Fast qw(:standard);
$COUNTER = 0;
while (new CGI::Fast) {
print header;
print start_html("Fast CGI Rocks");
print
h1("Fast CGI Rocks"),
"Invocation number ",b($COUNTER++),
" PID ",b($$),".",
hr;
print end_html;
}
There exist a fcgi-bin/test-python.fcgi whose content is (the file is executable by all, and readable by owner and group):
#!/usr/bin/python
def myapp(environ, start_response):
start_response('200 OK', [('Content-Type', 'text/plain')])
return ['Hello World!\n']
try:
from flup.server.fcgi import WSGIServer
WSGIServer(myapp).run()
except:
import sys, traceback
traceback.print_exc(file=open("errlog.txt","a"))
The issue
Although both fcgi-bin/test-perl.fcgi and fcgi-bin/test-python.fcgi runs normally when executed from the command‑line, none seems to work when invoked, e.g. as http://test.loc/fcgi-bin/test-perl.fcgi or http://test.loc/fcgi-bin/test-python.fcgi.
Nothing at all happens, and after some delay, I get an Error 500, and Apache error logs contains multiple entries looking like:
[<date>] [error] [client <IP>] FastCGI: comm with (dynamic) server "/<…>/fcgi-bin/<script>.fcgi" aborted: (first read) idle timeout (30 sec), referer: <referrer>
[<date>] [error] [client <IP>] FastCGI: incomplete headers (0 bytes) received from server "<…>/fcgi-bin/<script>.fcgi", referer: <referrer>
I've spent hours and hours searching the web trying to understand why it does not work, and finally decided to give up and ask for some help here.
Any pointers and check list welcome. Feel free to ask for any missing details you may feel to be relevant or worth checking.
Enjoy a nice day.
-- edit --
Issue update
In my own reply to my own question, I mentioned a weird case where things were looking suddenly fine without reasons. I later discovered this was only partly fine.
In the same virtual host, so with the exact same server configuration, some scripts, which are exactly the same (and with exact same access rights), fails depending on their location.
As a remainder, here is what's in the site configuration:
<DirectoryMatch /fcgi-bin>
Options +ExecCGI
<FilesMatch "^[^\.]+$">
SetHandler fastcgi-script
</FilesMatch>
</DirectoryMatch>
With the above, only scripts in /fcgi-bin are handled as FastCGI script. But I also have some elsewhere (still for testing): one in /cgi-bin and one in / (i.e. in the public_html directory). For this purpose, .htaccess contains this entry:
Options +ExecCGI
AddHandler fastcgi-script .fcgi
So the two others FastCGI script should work the same as the one in /fcgi-bin, but they don't, and for the time, they invariably terminates with a connexion time‑out, just like the one /fcgi-bin first did.
This makes me feel something may be wrong with the mod_fastcgi module (known bug? else?). So far, this module seems to act rather randomly.
-- edit 2 --
The above in the first edit, was an error of mine: the group was wrong with the other scripts, it had to be www-data, but it was not. So is something is wrong, stick to the answer I gave, that is, try to look at the FastCgiConfig, and see if it solve anything or at least if it honours the time‑out options.
