VERITAS Volume Manager 3.5 Administrator's Guide (September 2002)

Chapter 2, Administering Disks
Rootability
71
volumes, and then loads this configuration into the VxVM kernel driver. At this point,
I/O can take place forthese temporaryroot and swap volumes by referencingthe device
number set up by the rootability code.
When the kernel has passed control to the initial user procedure, the VxVM configuration
daemon (vxconfigd) is started. vxconfigd reads the configuration of the volumes in
the rootdg disk group and loads them into the kernel. The temporary root and swap
volumes are then discarded. Further I/O for these volumesis performed using the VxVM
configuration objects that were loaded into the kernel.
Setting up a VxVM Root Disk and Mirror
Note These procedures should be carried out at init level 1.
To set up a VxVM root disk and a bootable mirror of this disk, use the vxcp_lvmroot
utility. This command initializes a specified physical disk as a VxVM root disk named
rootdisk## (where ## is the first number starting at 01 that creates a unique disk
name), copies the contents of the volumes on the LVM root disk to the new VxVM root
disk, optionallycreates a mirror ofthe VxVMroot disk onanother specifiedphysical disk,
and make the VxVM root disk and its mirror (if any) bootable by HP-UX.
The following example shows how to set up a VxVM root disk on the physical disk
c0t4d0:
# /etc/vx/bin/vxcp_lvmroot -b c0t4d0
Note The -b option tovxcp_lvmroot uses the setboot command to define c0t4d0 as
the primary bootdevice. Ifthis optionis notspecified, the primary boot device is not
changed.
If the destination VxVM root disk is not big enough to accommodate the contents of the
LVM root disk, you can use the -R option to specify a percentage by which to reduce the
size of the file systems on the target disk. (This takes advantage of the fact that most of
these file systems are usually nowhere near 100% full.) For example, to specify a size
reduction of 30%, the following command would be used:
# /etc/vx/bin/vxcp_lvmroot -R 30 -v -b c0t4d0
The verbose option, -v, is specified to give an indication of the progress of the operation.
Caution Only create a VxVM root disk if you also intend to mirror it. There is no benefit
in having a non-mirrored VxVM root disk for its own sake.