Despite efforts to keep servers in sync, directory servers can begin to show incoherent data. Typically, this occurs in the following circumstances:
A disk error taints the stored data
A memory error leads to an error in processing data
A software bug leads to bad data or missing changes
In such cases, tracking and replaying changes is not sufficient to synchronize the incoherent data.
An automatic repair mechanism is provided, which leverages historical information inside entries to determine what the coherent data should be. The replication mechanism then repairs the data on directory servers where the data is bad or missing. The auto repair mechanism is implemented as an LDAP application, and runs on the hosts that run replication servers.
The auto repair application can run in different modes. Depending on the mode in which it is run, the auto repair application performs the following tasks:
Repairs inconsistencies manifested as an error when the server was replaying modifications
Repairs inconsistencies detected by the administrator
Periodically scans directory entries to detect and repair inconsistencies
Note - In the current directory server release, the auto repair mechanism must be run manually. For more information, see Detecting and Resolving Replication Inconsistencies in Sun OpenDS Standard Edition 2.0 Administration Guide.