Openfire needs the configuration file conf/openfire.xml and if you are using the embedded database embedded-db/*
If you use an external database you may access it with JDBC and may want to use database specific functions to create a shadow or mirror database or a database cluster. If you use LDAP/AD you may also want to run an LDAP shadow.
As Openfire uses a database cache you should make sure that only one instance is active and running.