Corrupted Rollback Segments

User ShutDown DB Instance and caused the rollback segment crashed, ...

At 26,Dec. 2005, Got a call from a friend that , his db's rbs tablespace increased over 6GB cause some block corruption of a rbs, and he shutdown the db server, then restart, but found that the r02 cannot mark available with the smon, Then I suggest him do like following:

1. Add the parameter "_corrupt_rollback_segments"=(R02);

2. Shutdown and restart the db.

3. Drop the rollback segment and the rbs tablespace;

4. create tablespace and rollback segment

5. exp all data from db.

6. delete the db and re-create them and imp.