Maintaining a Storage Array 916Maintaining a Storage ArrayMaintenance covers a broad spectrum of activities. Its goal is to keep a storagearray operational and available to all hosts. This chapter provides descriptions ofcommand line interface (CLI) and script commands that you can use to performstorage array maintenance. The commands are organized into four sections:• Routine maintenance• Performance tuning• Troubleshooting and diagnostics• Recovery operationsThe organization is not a rigid approach, and you can use the commands asappropriate for your storage array. The commands listed in this chapter do notcover the entire array of commands you can use for maintenance. Othercommands, particularly the set commands, can provide diagnostic ormaintenance capabilities.Routine MaintenanceRoutine maintenance involves those tasks you might perform periodically toensure that the storage array is running as well as possible or to detectconditions before they become problems.Running a Media ScanMedia scan provides a method of detecting physical disk media errors beforethey are found during a normal read from or write to the physical disks. Anyerrors detected are reported to the Major Event Log (MEL). Media scanprovides an early indication of a potential drive failure and reduces thepossibility of encountering a media error during host operations. A mediascan is performed as a background operation and scans all data andconsistency information in defined user virtual disks. A media scan runs on allvirtual disks in the storage array with the following conditions:• An Optimal status• No modification operations in progress
