The activeUserRegistry property appears on line 2.
If the configuration is federated (which is the out-of-the-box default), the value will be WIMUserRegistry_1.
If the configuration is standalone, the value will be LDAPUserRegistry_1.
Running the Portal configuration task, wp-modify-ldap-security, will change the security configuration to standalone. Among other things, a standalone configuration does not support multiple repositories, including multiple LDAP servers. If your architecture requires multiple LDAP servers and you have a standalone security configuration, run the config task wp-modify-federated-security to "switch" or convert to a federated configuration before running any tasks to add another repository.