Information
The PidFile directive sets the file path to the process ID file to which the server records the process id of the server, which is useful for sending a signal to the server process or for checking on the health of the process.
Rationale:
If the PidFile is placed in a writable directory, other accounts could create a denial of service attack and prevent the server from starting by creating a PID file with the same name.
Solution
Find the directory in which the PidFile would be created. The default value is the ServerRoot/logs directory.
Modify the directory if the PidFile is in a directory within the Apache 'DocumentRoot'.
Change the ownership and group to be root:root, if not already.
Change the permissions so that the directory is only writable by root, or the user under which Apache initially starts up (default is root).
Default Value:
The default process ID file is logs/httpd.pid.