If you have added database devices, or created or altered databases since the last database dump, use disk refit to rebuild the sysusages and sysdatabases tables.
disk refit can be run only from the master database and only by a system administrator. Permission cannot be transferred to other users. Its syntax is:
disk refit
SAP ASE shuts down after disk refit rebuilds the system tables. Examine the output while disk refit runs and during the shutdown process to determine whether any errors occurred.