HP 3PAR InForm OS 3.1.1 CLI Administrator's Manual

NOTE: The output for the command listed below is displayed in the same format as the showpd
-space command output example in “Determining Total Physical Disk Capacity” (page 111).
• To display the capacity information for a single physical disk, issue the showpd -space
<PD_ID> command, where <PD_ID> is the physical disk whose capacity information is
shown.
Spare Chunklets
Some chunklets are identified as spares when the system is first set up at installation. Data from
other chunklets is moved or reconstructed onto these spare chunklets in response to a chunklet or
disk failure or when a drive magazine needs to be serviced. This initial spare storage totals the
amount of storage in a single drive magazine, using the largest size physical disks.
NOTE: Local chunklets are chunklets on disks, which are used by the node that owns the logical
disk for the chunklet being relocated.
How spare chunklets work:
• When a connection is lost to a physical disk or a physical disk fails, all future writes to the
disk are automatically written to a logging logical disk until the physical disk comes back
online or until the time limit for logging is reached. Logging disk space is allocated when the
system is set up.
• If the time limit for logging is reached, or if the logging logical disk becomes full, relocation
of chunklets on the physical disk to other chunklets, free chunklets or allocated spares, starts
automatically. Free chunklets are chunklets that are not used by the system.
• For automatic relocations, the system uses up to a maximum of one disk worth of chunklets
per system node.
• If the system uses up its free or spare chunklets for relocation, an alert is generated.
• Once the spare and free chunklets are used up, automatic relocation no longer occurs. In
most cases, some data redundancy is lost. The system also generates an alert.
Viewing Spare Chunklets
Use the showspare command to display information about all spare chunklets. If a spare chunklet
is in use, the showspare output includes the name and ID of the logical disk using it, as well as
the chunklet’s position on the logical disk. If the spare chunklet is not in use, it is listed as
available, and the columns relating to the logical disk show only dashes.
The following example displays information about two spare chunklets, 0 and 1, on physical disk
23:
%cli showspare
PdId Chnk LdName LdCh State Usage Media Sp Cl From To
23 0 ---- --- normal available valid Y Y --- ---
23 1 sales1.0 2 normal ld valid Y Y --- ---
The fields in this output provide the following information:
• PdId. The physical disk on which the chunklets reside.
• Chnk. The position on the physical disk of the spare chunklets.
• LdName. The name of the logical disk that is using the spare chunklet.
• LdCh. The position of the chunklet on the logical disk.
• State. The state of the chunklet as identified by the kernel. Can be normal, none (hasn’t
been used by any logical disk), or failed.
Spare Chunklets 113