If you are upgrading from a 0.x NiFi instance, you can convert your previously configured users and roles to the multi-tenant authorization model. In the 'authorizers.xml' file, specify the location of your existing 'authorized-users.xml' file in the "Legacy Authorized Users File" property.

Here is an example entry:

<authorizers>
    <userGroupProvider>
        <identifier>file-user-group-provider</identifier>
        <class>org.apache.nifi.authorization.FileUserGroupProvider</class>
        <property name="Users File">./conf/users.xml</property>
        <property name="Legacy Authorized Users File">/Users/johnsmith/config_files/authorized-users.xml</property>

        <property name="Initial User Identity 1"></property>
    </userGroupProvider>
    <accessPolicyProvider>
        <identifier>file-access-policy-provider</identifier>
        <class>org.apache.nifi.authorization.FileAccessPolicyProvider</class>
        <property name="User Group Provider">file-user-group-provider</property>
        <property name="Authorizations File">./conf/authorizations.xml</property>
        <property name="Initial Admin Identity"></property>
        <property name="Legacy Authorized Users File">/Users/johnsmith/config_files/authorized-users.xml</property>

        <property name="Node Identity 1"></property>
    </accessPolicyProvider>
    <authorizer>
        <identifier>managed-authorizer</identifier>
        <class>org.apache.nifi.authorization.StandardManagedAuthorizer</class>
        <property name="Access Policy Provider">file-access-policy-provider</property>
    </authorizer>
</authorizers>

After you have edited and saved the 'authorizers.xml' file, restart NiFi. Users and roles from the 'authorized-users.xml' file are converted and added as identities and policies in the 'users.xml' and 'authorizations.xml' files. Once the application starts, users who previously had a legacy Administrator role can access the UI and begin managing users, groups, and policies.

The following tables summarize the global and component policies assigned to each legacy role if the NiFi instance has an existing 'flow.xml.gz':