If a critical dbspace is damaged because of a disk failure or corrupted data, the database server goes offline automatically. If a critical dbspace goes down, you must perform a cold restore of all critical dbspaces.
The database server must be offline on Dynamic Server or in microkernel mode on Extended Parallel Server for a cold restore. You can perform a cold restore of all storage spaces regardless of whether they were online or offline when the database server went down.
Perform a cold restore when the database server fails or you need to perform one of the following tasks:
A cold restore starts by physically restoring all critical storage spaces, then the noncritical storage spaces, and finally the logical logs. The database server goes into recovery mode after the reserved pages of the root dbspace are restored. When the logical restore is complete, the database server goes into quiescent mode. Use the onmode command to bring the database server online. For more information, see Performing a Cold Restore.
A cold restore can be performed after a dbspace has been renamed and a level-0 backup of the rootdbs and renamed dbspace is performed.