If a server has been offline for a period of time longer than the replication purge delay, you must run the dsreplication initialize command to bring the replica into sync with the topology.
Any missed changes are detected at the time of server startup. A missed change is a change that the replica detects it needs, but the change is not found within any other replication server's replicationChanges backend stored in the /changelogDb server root path.
If missed changes are detected, the server enters lockdown mode, where only privileged clients can make requests. Any other server that is not missing changes can be used as a source for dsreplication initialize.
If the server requires a manual backup and restore, perform the following steps, which are equivalent to dsreplication initialize.