/etc/opt : Configuration files for /opt

Host-specific configuration files for add-on application software packages must be installed within the directory /etc/opt/<subdir>, where <subdir> is the name of the subtree in /opt where the static data from that package is stored.

No structure is imposed on the internal arrangement of /etc/opt/<subdir>.

If a configuration file must reside in a different location in order for the package or system to function properly, it may be placed in a location other than /etc/opt/<subdir>.

Refer to the rationale for /opt.