You must run the idsync resync command also for the failover installation. The links between the entries are already established and idsync resync is only required to prime the object cache database for the Active Directory Connector. Therefore, it is run with the -u option. To avoid overloading Message Queue with log messages: the Message Queue Broker's maximum memory is increased, the Identity Synchronization for Windows log level is changed to INFO, and idsync resync is run over the entire user population in batches. The script above is modified slightly and run on the failover installation Core machine, config-eu.gt.com. The parameters at the top of the script are changed, and the -i NEW_LINKED_USERS option is replaced with just -u.