3PAR InForm® OS 2.2.4 Concepts Guide (320-200085 Rev B, March 2009)

B.2
Disk Replacement
3PAR InForm OS Concepts Guide InForm OS Version 2.2.4
B.1 Disk Replacement
When a physical disk failure occurs, the disk is no longer usable by the InServ system, and must
be replaced. As a physical disk fails, the InServ system automatically relocates the chunklets in
this disk to other disks in the system. For additional information on how chunklets are
relocated, see Appendix A, Sparing. When replacing the physical disk, the chunklets from all of
the disks in the drive magazine must be managed during the replacement procedure.
Chunklet management is achieved by:
■ Completely relocating the chunklets during the disk replacement procedure.
■ Relocating the chunklets from the failed disk, and then temporarily diverting data writes to
chunklets from the valid disks to logging logical disks (see 3PAR Storage Concepts and
Terminology on page 2.2 for information on logging logical disks).
To perform these procedures use the
servicemag command.
B.2 Using the servicemag Command
When the servicemag command is issued, all chunklets from the physical disks on the drive
magazine being serviced are relocated to other free or spare chunklets in the system.
When this command is issued, all chunklets are marked as
normal,smg. This state indicates an
active
servicemag operation on the disks.
To relocate chunklets, issue the
servicemag start command, specifying the number of the
drive cage and position of the drive magazine with the failed disk within the drive cage.
Once the
servicemag start operation has been initiated, and before the servicemag
resume
command is issued, if there is any I/O on the chunklets marked normal, smg, the
chunklets’ state changes to logging.
Once the chunklets have been relocated, you can then physically replace the failed disk. When
the disk has been replaced, use the
servicemag resume command to move relocated
cli% servicemag start 1 0.2
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