SCF Reference Manual for the Storage Subsystem (G06.27+, H06.04+)

Managing Magnetic Disks
SCF Reference Manual for the Storage Subsystem—529937-008
7-2
Managing Disks
Managing Disks
When managing disks, review these special considerations:
•
Managing the System Disk on page 7-2
•
Recovering From the Loss of a Path to a Disk on page 7-2
•
Troubleshooting Disks on page 7-2
Managing the System Disk
You cannot stop access to the system disk because important processes have their
object files and swap files on it. Therefore, you cannot stop the last path to the system
disk. You must take special precautions when performing some procedures:
•
If you have to replace the disk bootstrap program on the system disk, make sure it
is mirrored. See Changing Two Nonmirrored Disks Into a Mirrored Volume on
page 6-14.
•
Do not issue a STOPOPENS Command (page 14-135) on the system disk.
Recovering From the Loss of a Path to a Disk
If the X fabric or Y fabric fails, internal disk paths using the failed fabric go down. After
repairing a fabric failure, these failed disk paths are not automatically restarted. They
remain HARDDOWN until you restart the disk process. The storage subsystem never
attempts to use the failed path, which creates a potential single point of failure.
To restore the paths to all disks that use the repaired fabric, see Resetting a Group of
Magnetic Disks on page 7-13.
Troubleshooting Disks
For more information about troubleshooting disk drives, see the Service and Support
Library of the NonStop Technical Library (NTL).