Hi, I migrated a few websites at ISPConfig3 server but sometimes I face really big problem. Web aplication return HTTP 500(Failed to load resource: the server responded with a status of 500 (Internal Server Error)) but there are no errors in log, no errors in cms log .. I really do not know how debug this. It is no the major HTTP 500 error like if you got something bad in htaccess, it try show page but in middle it stops and return 500 error.
There must be an error listed in the error.log of the website, you can find the log file in the log subfolder of the site. Do not look into the global error.log, website errors are logged in the website logs only.
Empty no error in global error log, no error in website log. For example now I solve one 500 error issue. The website use short_tags in some PHP files, if I force PHP verbose log I see: Call to undefined function xxxx() So I start finding this function and found it in file with <? starting sequence (short tag) So I allow short tags in site -> option -> custom php.ini .. But I really confuse why page return error 500 and do not write any log. For example last errors in log: [Tue Jun 09 13:46:34.677182 2020] [fcgid:warn] [pid 24315] [client 193.165.153.125:41945] mod_fcgid: stderr: PHP Notice: Use of undefined constant psc - assumed 'psc' in /var/www/clients/client18/web30/web/fpdf/smlouva_internet.php on line 210, referer: http://www.itconsulting.cz/cz/internet/objednavka-sluzeb [Tue Jun 09 13:46:34.677186 2020] [fcgid:warn] [pid 24315] [client 193.165.153.125:41945] mod_fcgid: stderr: PHP Notice: Use of undefined constant nadpis - assumed 'nadpis' in /var/www/clients/client18/web30/web/fpdf/smlouva_internet.php on line 245, referer: http://www.itconsulting.cz/cz/internet/objednavka-sluzeb [Tue Jun 09 13:46:34.677190 2020] [fcgid:warn] [pid 24315] [client 193.165.153.125:41945] mod_fcgid: stderr: PHP Notice: Use of undefined constant pausal - assumed 'pausal' in /var/www/clients/client18/web30/web/fpdf/smlouva_internet.php on line 265, referer: http://www.itconsulting.cz/cz/internet/objednavka-sluzeb [Tue Jun 09 13:46:34.677193 2020] [fcgid:warn] [pid 24315] [client 193.165.153.125:41945] mod_fcgid: stderr: PHP Notice: Use of undefined constant zrizeni - assumed 'zrizeni' in /var/www/clients/client18/web30/web/fpdf/smlouva_internet.php on line 267, referer: http://www.itconsulting.cz/cz/internet/objednavka-sluzeb [Tue Jun 09 13:46:34.677197 2020] [fcgid:warn] [pid 24315] [client 193.165.153.125:41945] mod_fcgid: stderr: PHP Notice: Undefined variable: priority in /var/www/clients/client18/web30/web/fpdf/smlouva_internet.php on line 441, referer: http://www.itconsulting.cz/cz/internet/objednavka-sluzeb [Tue Jun 09 13:46:34.677203 2020] [fcgid:warn] [pid 24315] [client 193.165.153.125:41945] mod_fcgid: stderr: PHP Notice: Undefined variable: priority in /var/www/clients/client18/web30/web/fpdf/smlouva_internet.php on line 442, referer: http://www.itconsulting.cz/cz/internet/objednavka-sluzeb [Tue Jun 09 13:46:34.677207 2020] [fcgid:warn] [pid 24315] [client 193.165.153.125:41945] mod_fcgid: stderr: PHP Notice: Use of undefined constant nadpis - assumed 'nadpis' in /var/www/clients/client18/web30/web/fpdf/smlouva_internet.php on line 445, referer: http://www.itconsulting.cz/cz/internet/
E.g. if you have logging disabled in PHP completely, then PHP will not log any error. Check log settings in php.ini.
