rollback segment needs recovery

In case there are some problems ( incomple or unfininshed recovery, media error ) , youo probably have a rollback segment that is in the state  needs recovery .

In this case, the best way is to follow this link : http://www.runningoracle.com/product_info.php?products_id=283  .

Put the following event

event="10015 trace name context forever, level 10"

 Find the rollback segment that is corrupted ( eg _SYSSMU6$ )  and put it offline in the init parameter file.

_offline_rollback_segments=_SYSSMU6$

You can also see if there is an active transaction in your database (see note 1291009.1)

SELECT KTUXEUSN, KTUXESLT, KTUXESQN, /* Transaction ID */
              KTUXESTA Status,
              KTUXECFL Flags
               FROM x$ktuxe
     WHERE ktuxesta!='INACTIVE' ;