I think that here it's just the generic Apache errors that are seen in
I would insert a call to
error_log('test'); into some PHP logic that is known to get interpreted when some specific page is refreshed, and if that's not seen in
/var/log/php-errors.log then I'd suspect that the versions upgraded to have some kind of a different config or permissions scheme that made the old config stop working.
I'd recommend going through the 'Error handling and logging' section in
/etc/php/php.ini, and checking for proper values for other directives. The directive
error_reporting should be set to
E_ALL & ~E_DEPRECATED & ~E_STRICT. The directive
log_errors should be
If just a filename (but no path) is specified for
error_log, then the file will appear in the same directory as the PHP script that calls
I'd also recommend specifying
error_log, refreshing the page, and then
ls /tmp to see if the file is there.
If the file is not there, login as root, and do a search for the file name across the whole file system so see where it ended up.
Generally, the proper config to get PHP error log working in a particular directory changes across different versions of Apache, PHP, and various distros.
I can say that on Arch Linux with Apache 2.4, PHP 5.5.11 and systemd version 212-1 the config above will make the PHP error log end up somewhere similar to