Purging Historical Replication Data

Oracle Unified Directory maintains a history of all changes that have been made on the server as a result of replication operations. This historical replication data is stored in an attribute of each user entry, and can eventually take up a large amount of space on your disk. Historical information is therefore purged when an entry is modified, or when you specifically run a command to purge the data.

By default, information that is older than one day is purged. You can specify the age of data that should be purged by setting the value of the conflicts-historical-purge-delay property of the replication domain. The following example specifies that data older than five days should be purged. Note that the value of the property is expressed in minutes.

$ dsconfig -h localhost -p 4444 -D "cn=directory manager" -w password -X -n \
  set-replication-domain-prop --provider-name "Multimaster Synchronization" \
  --domain-name dc=example,dc=com --set conflicts-historical-purge-delay:7200m

You can also purge historical data immediately, or schedule a task to purge the data at a specific time. Imagine, for example, that you initialize a server with a large number of entries, then perform a significant number of changes on these entries. The resulting replication historical data will increase the size of the database quite substantially. If your server is then used mainly for read operations, the large database size remains, because no modifications are made to trigger a purge of the historical data. In this case, you can launch a once off purge task to remove the historical data that was generated by the initial modifications, and return the database to a more accurate size.

Because the purge process can take some time, you are required to specify the maximum duration of the purge (in seconds). To purge historical data immediately, run the following command:

$ dsreplication -h localhost -p 4444 --adminUID admin --adminPassword password \
  purge-historical --maximumDuration 3600 --baseDN dc=example,dc=com -X -n

For information about scheduling commands as tasks, see Configuring Commands As Tasks.