Disk availability
The following information lists the possible values of disk availability, and what they mean.
A disk's availability determines whether GPFS is able to read and write to the disk.
There are four possible values for availability:
- up
- The disk is available to GPFS for normal read and write operations.
- down
- No read and write operations can be performed on the disk.
- recovering
- An intermediate state for disks coming up, during which GPFS verifies and corrects data. A write operation can be performed while a disk is in this state, but a read operation cannot, because data on the disk being recovered might be stale until the mmchdisk start command completes.
- unrecovered
- The disk was not successfully brought up.
Disk availability is automatically changed from up to down when GPFS detects repeated I/O errors. You can also change the availability of a disk by issuing the mmchdisk command.