Administering virtual disks

Converting filesystems to virtual disks

A traditional filesystem exists as a physical disk division. Because virtual disks provide more flexible storage than divisions, consider converting all your filesystem divisions to virtual disks. Once you have converted a division to a virtual disk, it will no longer be accessible via the divisions device nodes. It will be accessible via the virtual disk device nodes.

To migrate from a system based on divisions to virtual disks, unmount the filesystems on the division that you wish to convert, then create a simple virtual disk for each division using the Virtual Disk Manager, as described in ``Adding virtual disks''. Allocate the division to the virtual disk, as described in ``Allocating or modifying disk pieces''. The division will be deleted automatically once the virtual disk is assigned to it.

When the filesystem is in a simple virtual disk configuration, migration to other array configurations can be done without taking the disk offline. The division should not be accessed while it is migrated.

For your existing divisions:

  1. Unmount the filesystems on the divisions that you want to convert.

  2. For each division, select New from the Disk menu, add a simple one-piece virtual disk as described in ``Adding virtual disks'', and allocate the division to the virtual disk. This overlays each division with a simple virtual disk.

  3. For each division, select Modify from the Disk menu, and migrate the simple virtual disk to the desired RAID type. For example, if you want to create a mirrored filesystem, select Mirror and allocate a spare disk piece to the parity piece. If migrating to a disk array, you must have spare disk space for temporary storage.

  4. Use the Filesystem Manager to update the information about mounted filesystems. Replace the filesystems' divvy device nodes with their virtual disk ones. For example, if you have replaced the /u filesystem with a mirror vdisk4, mount /dev/dsk/vdisk4 instead of /dev/u on the /u mount point.

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© 2003 Caldera International, Inc. All rights reserved.
SCO OpenServer Release 5.0.7 -- 11 February 2003