Use the following methods to check for replication inconsistencies:
Check for information in the replication log file. The replication log file is configured by default and lists inconsistencies that are detected by the replication mechanism. Imagine, for example, that a modify operation is performed on an entry that is missing from one directory server in the topology. When replication attempts to replay this operation to that server, it will detect the problem and produce an error in the logs/replication error log. This kind of error will not stop replication, but the operation will not be replayed and the administrator will need to repair the inconsistency.
Pay attention to errors reported by client applications or users. Client applications or users might experience errors when accessing the directory server that might be due to replication inconsistencies.
Make regular checks for database consistency. With the current directory server release, these checks must be performed manually, using searches or database exports. A future directory server release is expected to provide tools to check databases for consistency.