Seagate ST34572WC Spezifikationen PDF herunterladen (Seite 20)

You can select a particular target disk or disks, if desired. For example, to move all the physical

extents from c0t5d0 to the physical volume c0t2d0, enter the following command:

# pvmove /dev/dsk/c0t5d0 /dev/dsk/c0t2d0

The pvmove command succeeds only if there is enough space on the destination physical volumes to

hold all the allocated extents of the source physical volume. Before you move the extents with the

pvmove command, check the “Total PE” field in the pvdisplay source_pv_path command

output, and the “Free PE” field output in the pvdisplay dest_pv_path command output.

You can choose to move only the extents belonging to a particular logical volume. Use this option if

only certain sectors on the disk are readable, or if you want to move only unmirrored logical volumes.

For example, to move all physical extents of lvol4 that are located on physical volume c0t5d0 to

c1t2d0, enter the following command:

# pvmove -n /dev/vg01/lvol4 /dev/dsk/c0t5d0 /dev/dsk/c1t2d0

Note that pvmove is not an atomic operation, and moves data extent by extent. If pvmove is

abnormally terminated by a system crash or kill -9, the volume group can be left in an inconsistent

configuration showing an additional pseudo mirror copy for the extents being moved. You can

remove the extra mirror copy using the lvreduce command with the –m option on each of the

affected logical volumes; there is no need to specify a disk.

Removing the Disk from the Volume Group

After the disk no longer holds any physical extents, you can use the vgreduce command to remove

the physical volume from the volume group so it is not inadvertently used again. Check for alternate

links before removing the disk, since you must remove all the paths to a multipathed disk. Use the

pvdisplay command as follows:

# pvdisplay /dev/dsk/c0t5d0 --- Physical volumes ---

PV Name /dev/dsk/c0t5d0

PV Name /dev/dsk/c1t6d0 Alternate Link

VG Name /dev/vg01

PV Status available

Allocatable yes

VGDA 2

Cur LV 0

PE Size (Mbytes) 4

Total PE 1023

Free PE 1023

Allocated PE 0

Stale PE 0

IO Timeout (Seconds) default

Autoswitch On

In this example, there are two entries for PV Name. Use the vgreduce command to reduce each

path as follows:

# vgreduce vgname /dev/dsk/c0t5d0

# vgreduce vgname /dev/dsk/c1t6d0

If the disk is unavailable, the vgreduce command fails. You can still forcibly reduce it, but you must

then rebuild the lvmtab, which has two side effects. First, any deactivated volume groups are left out

of the lvmtab, so you must manually vgimport them later. Second, if any multipathed disks have

their link order reset, and if you arranged your pvlinks to implement load-balancing, you might have

to arrange them again.

Starting with the HP-UX 11i v3 release, there is a new feature introduced in the mass storage

subsystem that also supports multiple paths to a device and allows access to the multiple paths

simultaneously. If the new multi-path behavior is enabled on the system, and the imported volume

1 2 ... 15 16 17 18 19 20 21 22 23 24 25 ... 66 67

Kommentare zu diesen Handbüchern

Keine Kommentare

Seagate ST34572WC Spezifikationen Seite 20

Kommentare zu diesen Handbüchern

Verwandte Produkte und Handbücher für Software Seagate ST34572WC