Sudden 500 Internal Server Error on a 1yo script

[invisible]

I don't understand what's going on here. I have a cgi script i bought that i've run for 4 yeasrs on many servers with no problems. It's been on this particular server for over a year now, working perfectly. All of a sudden, I"m getting '500 Internal Server bla bla bla' when i try to login to the admin interface.

I've checked the error logs. All they say is '... malformed header from script. Bad header= bla ..."

I've done a search on the forums of both the software maker and this site. I can't find anything that even remotely looks like this problem.

A search of google turned up a similar problem but there was no solution given to the question in that forum.

Has anybody ever seen this before? What could cause this.

ASCII is not an issue, this was a working script 2 days ago.
Owner, group and permissions are correct.
It's only affecting 1 domain on a box that hosts 55 domains, and none of the others seem to have this problem.

??????????????????????????????

[chirpy]

Is it a perl CGI script or a PHP one? Has anything been upgraded on the server recently. If a perl script, could it be a perl module update recently?, if php, has php been upgraded or perhaps Zend Optimizer?

Also, have to checked the account in question hasn't reached its disk quota, or that the disk itself isn't out of space. Check /tmp and ensure that's got plenty of space.

[invisible]

Thanks for the quick reply Chirpy. It's a perl script but usees mysql. In fact, 5 of the other sites have scripts that use mysql too. I just incresed the quoota but that didn't do anything.

/tmp seems pretty empty. Only files are

.font-unix
.ICE-unix
horde_32001.log
mysql.sock
sess_15f1fd0dc1a0e3565a74a0d20fa51e78
total size 473Mb

Is it possible that heavy mysql usage from the other sites could cause this?

[brianoz]

Have you checked error_log in /etc/httpd/logs, and also audit_log (and in fact all logs on the machine) to see if you can see more details? 9 times out of 10 this solves it for me.

[chirpy]

You might also try adding this after the shebang at the top of the perl script:

(shebang is the #/path/to/interpreter)

use CGI::Carp qw(fatalsToBrowser);

Then try browsing to it again and see if it throws anything into your browser other than the 500 error.