vxvmconvert - convert LVM volume groups to VxVM disk groups

vxvmconvert

vxvmconvert is a menu-driven program to convert an IBM Logical Volume Manger (LVM) configuration to a Veritas Volume Manager configuration. Refer to the Veritas Foundation Suite Migration Guide for a detailed description of how to use the conversion procedure.

The vxvmconvert script is interactive and prompts you for responses, supplying defaults where appropriate. There is a Help facility at every prompt. Enter a question mark (?) at a prompt to display a context-sensitive help message.

With vxvmconvert you can identify LVM volume groups, list disks, analyze volume groups for conversion and complete the conversion of LVM volume groups to VxVM disk groups.

LVM configurations are converted at the volume group level. All disks used in a volume group are converted together. You cannot use vxvmconvert to convert unused LVM disks (those not part of an LVM volume group) to VxVM disks. To convert unused LVM disks, use reducevg to take the disk out of LVM control, and then use vxdiskadm to initialize the disk for VxVM use (see reducevg(1M) and vxdiskadm(1M) for more information).

vxvmconvert changes disks within LVM volume groups to VxVM disks by replacing areas of the disks used for LVM configuration information with the equivalent VxVM volume configuration information. Portions of the disks used for user data, such as file systems and databases, are not affected by the conversion.

The conversion process changes the names by which your system refers to the logical storage, so must be done offline. No applications can access data in the volume groups undergoing conversion. You must unmount file systems using those volumes and shut down any applications, such as databases, that might use the volumes directly.

Analyze LVM Volume Groups for Conversion
	Use this operation to analyze one or more LVM volume groups for conversion to use by VxVM. The analysis checks for problems that can prevent the conversion from completing successfully. It calculates the space required to add volume group disks to a Volume Manager disk group. More than one volume group may be entered at the prompt. A grep-like pattern may be used to select multiple volume groups.
	See ‘‘Volume Group Conversion Limitations’’ in the Veritas Foundation Suite Migration Guide for more information.
Convert LVM Volume Groups to VxVM
	Converts one or more LVM volume groups to one or more VxVM disk groups. This adds the disks to a VxVM disk group and replaces existing LVM volumes with VxVM volumes.
	vxvmconvert prompts you to name the VxVM disk group that replaces the LVM volume group being converted. A default is suggested at the prompt. For example, if you are converting a volume group vg08, vxvmconvert renames it as dg08.
	See ‘‘Planning for new VxVM logical volume names’’ and ‘‘Tailoring your VxVM Configuration’’ in the Veritas Foundation Suite Migration Guide for more information.
Rollback from VxVM to LVM
	Rollback reverts VxVM disk groups to LVM volume groups. vxvmconvert provides a limited snapshot capability for the LVM metadata in a converted volume group. A snapshot is a simple protection method to use during conversion.
	Caution: Do not use this operation if you modified the VxVM disk group since the conversion.
	See ‘‘Restoring the LVM Volume Group Configuration’’ in the Veritas Foundation Suite Migration Guide for more information.
Set path for saving VGRA records
	Use this option to set the location for storing VGRA records.
To allow for rollback, certain LVM metadata records must be saved. The largest of these records is the VGRA record for each physical volume in an LVM volume group. The default location for this record is in /etc/vx/reconfig.d/disk.d, which is generally on the root file system. For small records, this is no problem. However, when converting LVM volume groups with large VGDAs, the size of the VGRA for each physical volume may be over 64MB. For example, the space required to store the VGRAs for a 128-disk volume group could be over 8 gigabytes. As it is unlikely that a system has this much spare disk space in its root file system, this operation allows you to specify an alternative location.
List Disk Information
	Displays information about the disks on a system. You can obtain detailed information about a disk by entering a specific disk device address.
List LVM Volume Group Information
	The lsvg command displays a list of LVM volume groups. You can obtain detailed information about an LVM volume group at a specific disk device address.

lsvg(1M), reducevg(1M), vxdisk(1M), vxdiskadd(1M), vxdiskadm(1M), vxintro(1M)

Veritas Foundation Suite Migration Guide