Liferay has a highly extensible architecture. You decide what you want to override in Liferay - it has using an extension somewhere. This page topic indicates how to delegate Liferay's authentication and authorization functionality to WSO2 Identity Server.
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One of the challenges you may face in this integration is the LDAP Users/Groups import. You can connect an LDAP to Liferay, however, to authenticate users to Liferay against the underlying LDAP, it has to import all the users and groups to Liferay's underlying database, which is by default running on Hypersonic.
Since you You only need to keep the user data in a single LDAP to avoid this duplication. However, this is not straightforward as you need to write the complete persistence layer. Let's take a step back and see how Authentication and Authorization work in Liferay.
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