On restaring Apache, you may get the following error:

Nov 21 09:31:40 web httpd: Cannot load usr/local/apache/libexec/mod_log_bytes.so into server: /usr/local/apache/libexec/mod_log_bytes.so: cannot open shared object file: No such file or directory
Nov 21 09:31:40 web rc: Starting httpd: failed

Invalid command ‘BytesLog’, perhaps mis-spelled or defined by a module not included in the server configuration

This is most likely due to the cause that the mod_belimited.so, mod_log_bytes.so, or mod_bandwidth.so are deleted or corrupted. These 3 files are unique on cPanel based servers.

This error is received when the Apache HTTPD server has been messed up with some shared library files such as mod_auth_passthrough.so, mod_bwlimited.so and mod_log_bytes.so located in libexec directory, that have accidentally been deleted or corrupted.

The solution to the error is to recompile those shared library modules. You can easily compile these cPanel modules for Apache by using the following commands:

cd /usr/local/cpanel/apache
/usr/local/apache/bin/apxs -iac mod_log_bytes.c

/usr/local/apache/bin/apxs -iac mod_bwlimited.c

/usr/local/apache/bin/apxs -iac mod_bandwidth.c

After compilation, the .so files will automatically be copied to libexec directory for Apache HTTPD web server.