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Manual: Volume Manager 4.1 Migration Manager   

Existing Features in LVM not supported in VxVM

Some of the existing features in LVM are not supported in the current release of VxVM. Given below is a table with the unsupported LVM features, and possible workarounds in VxVM.

LVM features and VxVM equivalents

LVM Feature VxVM Equivalent

Physical volume groups

VxVM has no equivalent feature. The disk group feature of VxVM combines the logical volume group (VG) and physical volume group (PVG) of LVM.

Powerfail timeout feature: Automatically re-enable a disk or a path to a disk, after temporary error condition (resulting in

EPOWERF error on I/Os) disappears on that disk or path.

Powerfail timeout feature: After the EPOWERF error condition disappears, the reconfiguration command must be run manually to re-enable the paths and the disks which were disabled due to EPOWERF error. See the pfto feature in the vxdctl(1M) manual page for more information.

Logical Volume Timeout (LVTO). If LVTO on a logical volume is set to zero, which is the default, an I/O is retried forever.

VxVM does not support the LVTO feature. However, VxVM supports the powerfail timeout feature to handle transient error conditions. VxVM tries an I/O only on active paths to a disk; hence, it never retries indefinitely. See the powerfail timeout feature and also refer to the pfto feature in the vxpfto manual pages for more details.

Bad media block relocation.

VxVM relocates whole subdisks. Smaller granularity relocation is not supported. The bad block reallocation feature does not exist in VxVM because the vectoring of bad blocks is now done by most hardware.

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Product: Volume Manager Guides  
Manual: Volume Manager 4.1 Migration Manager  
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