HTTP 500 error when I run my Perl script

At my work place, we provide shared hosting and http 500 error is the most common in trouble tickets. Although everything is properly configured we still get reports of error.

Send MIME type

99% time – it was not servers fault at all. I found that the most common reason for HTTP 500 errors is not printing the MIME type before outputting data to the web browser. All you need following line before outputting data to the web browser:

print "Content-type: text/html\n\n";

Perl does not automatically generate HTML. Also try following few suggestions:

Permissions

You need to setup file permissions on perl script

chmod  755 perlscript.pl
chmod  +x perlscript.pl

Perl script location
It must be in cgi-bin directory (or directory configured to run perl). Some servers are configured to run your CGI scripts anywhere.

Error log file

Please check your log file to find errors in your Perl script.

tail -f /var/log/httpd/error.log
tail -f /var/log/httpd/access.log

Debug

Pass -wc option to perl script at shell prompt, enter:

perl -wc myscript.pl

It will often point out exactly where the trouble is.

I am not perl guru but as a sys admin, I need to look after this kind of problems. What other techniques all of you follow to troubleshoot Perl http 500 error problem?

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2 comments… add one
  • ft Jan 21, 2006 @ 2:32

    I suggest include the following line at the top of your perl script:

    #!/usr/bin/perl –w

    just my 2 cents

  • Anonymous Jan 21, 2006 @ 2:11

    Was browsing your site for something else I found this post. I can say use the CGI Perl module. It is more easy and you can avoid error 500. See CGI.pm doc @ here or
    here

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