Internal Server Error 500 in cache depence - no idea to solve

[stoutwind_de]

dear PrestaShopper's,

i am writing this post because i'm looking for about 5 hours for a solution to my problem.

 

The problem:
The following problem appears on our shop (Version 1.6.09 - up to date, running since approx. 4 weeks now) and i absolutely have no idea to fix this: Always when i call our shop frontend or backend (makes no difference) i get an Internal Server Error 500. This error disappears after page reload or deleting cache in browser (there is no difference in different browsers - exact same situation). After disappearing i can browse on page normally. When idling, after some time the error reappars when clicking a link on our frontend or backend oder refreshing current page. The time interval i could not detect until yet (i think it is around 5 minutes).

There is shown a blank error message:

 

"The server encountered an internal error or misconfiguration and was unable to complete your request.

Please contact the server administrator, [email protected] and inform them of the time the error occurred, and anything you might have done that may have caused the error.

More information about this error may be available in the server error log."

 

 

When did i first recognize something is going wrong:

I did not change anything in shop configuration. The error just appeared the first time while i was editing a product's details and adding some images. Now the error is like a bad ghost

 

How i tried to resolve:

It's not the error message which should be displayed by PrestaShop itself  - it's the blank one generated by server (Apache or something). The following this i did:

1. enabled the flag define('_PS_MODE_DEV_', true in config/defines.inc.php
2. deleted the .htaccess and generated a new one's default file by prestashop which should be an exact and correct working file.
3. checked .htaccess permission to are set as 640. I already tried 777 and 755.
4. enabled and disabled userfriendly URL rewrite in SEO/URL configuration
5. deactivated CDN-Servers
6. deactivated cachefs of prestashop let the user cache data with browser instead (when using cachefs the Server Error did not went ago by refreshing the page - i logically had to delete the cachefs folder via FTP in prestashop directory)
7. disabled/enabled CCC
8. changed the PHP Version on our host from 5.3 to 5.5 and to 5.6 with and without PHP Boost. No changes each version..
9. changed php.ini parameters to different things. There was no difference when changing any line belonging to error handling/displaying. My files actually looks like:

#php.ini
############

memory_limit=128M
max_input_vars=6000;
display_errors=1;    
display_startup_errors=1;
log_errors=1;
log_errors_max_len=1024;
ignore_repeated_errors=0;
ignore_repeated_source=0;
report_memleaks=1;
track_errors=1;
html_errors=1;
xmlrpc_errors=1;

Deleting the php.ini does nothing change. As you know this file is not needed at all by PrestaShop

I tried many different combinations without any visible success. This error is horrible.

The error log of our hosting server gives different entries. The line which continueously appears is:

02.10.2014 16:22:44 stoutwind.de [client 77.64.52.0] FastCGI: "/home/strato/http/fastcgi/rid/08/99/53970899/htdocs/prestashop/admin1668/index.php" aborted: incomplete headers (0 bytes) received from server after 6 sec, referer:

there are also two other messages which repeat sometimes:

28.09.2014 21:10:16 stoutwind.de [client 77.64.52.0] Premature end of script headers: index.php
02.10.2014 14:14:06 stoutwind.de [client 77.64.52.0] Request exceeded the limit of 4 internal redirects due to probable configuration error. Use 'LimitInternalRecursion' to increase the limit if necessary. Use 'LogLevel debug' to get abacktrace.

Googling for those error messages gave me no results matching the discribed issue that the problem disappears by refreshing the page. Could it be have something to do with SSL connection? I really think there is no problem with .htaccess or php.ini. I guess it has to do with PHP in general, a PrestaShop plugin/update, a configuration setting or SSL.

If anyone has an idea please tell me. I don't know how to look up for this special case. You are my last hope

Best wishes, Mario Voigt
 

Edited October 5, 2014 by stoutwind_de (see edit history)

[Dh42]

Ask your server to increase the amount of internal redirects that fastcgi will accept and also increase the fastcgi wait timeout also. Send those error messages to them it should help them out. 

[stoutwind_de]

thank you for your quick reply. I will request this to the hosting company. But i actually do not understand what's the reason for the error. Why does it occure now but not at the beginning when i first set up the shop. What does affect the internal redirect rate?

 

regards, Mario Voigt

[horntrader]

Your web host should have the answer to the issue in their general error logs. 500s don't show up in the php error logs. Did they help you with your issue? Probably an issue with fastcgi, maybe even caching.

 

Jamie

[stoutwind_de]

Hello,

 

i got the problem solved without the support. But i don't understand why it works now. I deleted img/tmp files and smarty cache. But i wonder why i never got an appropriate error message from prestashop instead i got from the server

[Admin@s]

Maybe it will be useful information for some of you:

 

I had problems with HTTP Error 500... and spend many hours reading forum topics and trying many solutions... turning on error reporting / disabling some modules / deleting cache/smarty / reuploding files / cheking server configuration and many more...

 

Finaly I found solution in some blog, away from PS community Its:

1. Turn Off and turn On the SEO friendly URLs. This will generate the a .htaccess file on your root.
2. Download the .htaccess file. Comment the line “SetEnv HTTP_MOD_REWRITE On” by putting # before the line and reuplod.
3. If the version of PHP running on your server is 5.4 (5.5 / 5.6), change it to 5.2.

 

This should solve your problem

[mma87]

Maybe it will be useful information for some of you:

 

I had problems with HTTP Error 500... and spend many hours reading forum topics and trying many solutions... turning on error reporting / disabling some modules / deleting cache/smarty / reuploding files / cheking server configuration and many more...

 

Finaly I found solution in some blog, away from PS community Its:

 

1. Turn Off and turn On the SEO friendly URLs. This will generate the a .htaccess file on your root.

2. Download the .htaccess file. Comment the line “SetEnv HTTP_MOD_REWRITE On” by putting # before the line and reuplod.

3. If the version of PHP running on your server is 5.4 (5.5 / 5.6), change it to 5.2.

 

This should solve your problem

 

 

Thank you!!!!