I installed the mod_qos module using the steps found here, every step went perfectly fine without any problems, however, when attempting to restart the apache service it returned the following error:apache2: Syntax error on line 203 of /etc/apache2/apache2.conf: Syntax error on line 1 of /etc/apache2/mods-enabled/qos.load: Cannot load /usr/lib/apache2/modules/mod_qos.so into server: /usr/lib/apache2/modules/mod_qos.so: undefined symbol: EVP_DecryptFinalThe contents of the qos.load file is just this line:LoadModule qos_module /usr/lib/apache2/modules/mod_qos.soHow do I solve this error?
(debian) installing mod_qos on apache results in error on start
debian;apache httpd;dynamic loading
This means that mod_qos is trying to use a part of a library that is not (yet) loaded or available. EVP_DecryptFinal should be a part of openSSL, so provided that you've got mod_ssl installed, try loading it before you load qos. 