GPFS: Administration and Programming Reference - IRA Home

suspended
Indicates that data is to be migrated off this disk.
being emptied
Transitional status in effect while a disk deletion is pending.
replacing
Transitional status in effect for old disk while replacement is pending.
replacement
Transitional status in effect for new disk while replacement is pending.
GPFS allocates space only on disks with a status of ready or replacement.
GPFS migrates data off of disks with a status of being emptied, replacing, or suspended, onto disks
with a status of ready or replacement. During disk deletion or replacement, data is automatically migrated
as part of the operation. The mmrestripefs command must be issued to initiate data migration from a
suspended disk.
See “Deleting disks from a file system” on page 29, “Replacing disks in a GPFS file system” on page 30,
and “Restriping a GPFS file system” on page 19.
Changing GPFS disk states and parameters
You might find it necessary to change a disk’s state if there is some indication of disk failure or if you need
to restripe the file system. Refer to “Displaying GPFS disk states” on page 31 for a detailed description of
disk states. You can change both the availability and status of a disk using the mmchdisk command:
v Change disk availability using the mmchdisk command and the stop and start options
v Change disk status using the mmchdisk command and the suspend and resume options.
Issue the mmchdisk command with one of the following four options to change disk state:
suspend
Instructs GPFS to stop allocating space on the specified disk. Place a disk in this state prior to
disk deletion or replacement. This is a user-initiated state that GPFS will never use without an
explicit command to change disk state.
Note: A disk remains suspended until it is explicitly resumed. Restarting GPFS or rebooting nodes
does not restore normal access to a suspended disk.
resume
Informs GPFS that a disk previously suspended is now available for allocating new space.
Resume a disk only when you’ve suspended it and decided not to delete or replace it. If the disk is
currently in a stopped state, it remains stopped until you specify the start option. Otherwise,
normal read and write access to the disk resumes.
stop Instructs GPFS to stop any attempts to access the specified disk. Use this option to inform GPFS
that a disk has failed or is currently inaccessible because of maintenance. A disk’s availability
remains down until it is explicitly started with the start option.
start Informs GPFS that a disk previously stopped is now accessible. GPFS does this by first changing
the disk availability from down to recovering. The file system metadata is then scanned and any
missing updates (replicated data that was changed while the disk was down) are repaired. If this
operation is successful, the availability is then changed to up.
If the metadata scan fails, availability is set to unrecovered. This could occur if other disks remain
in recovering or an I/O error has occurred. Repair all disks and paths to disks. See mmfsck. The
metadata scan can then be re-initiated at a later time by issuing the mmchdisk start command
again.
32 GPFS: Administration and Programming Reference