Veritas Volume Manager 5.1 SP1 Administrator"s Guide (5900-1506, April 2011)

Warning: If you mirror only selected volumes on the root disk and use spanning
or striping to enhance performance, these mirrors are not bootable.
See “Setting up a VxVM root disk and mirror” on page 119.
Booting root volumes
Note: At boot time, the system firmware provides you with a short time period
during which you can manually override the automatic boot process and select
an alternate boot device. For information on how to boot your system from a
device other than the primary or alternate boot devices, and how to change the
primary and alternate boot devices.
See the HP-UX documentation.
See the boot(1M) manual page.
See the pdc(1M) manual page.
See the isl(1M) manual page.
Before the kernel mounts the root file system, it determines if the boot disk is a
rootable VxVM disk. If it is such a disk, the kernel passes control to its VxVM
rootability code. This code extracts the starting block number and length of the
root and swap volumes from the LIF LABEL record, builds temporary volume and
disk configuration objects for these volumes, and then loads this configuration
into the VxVM kernel driver. At this point, I/O can take place for these temporary
root and swap volumes by referencing the 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 bootdg disk group and loads them into the kernel. The
temporary root and swap volumes are then discarded. Further I/O for these
volumes is performed using the VxVM configuration objects that were loaded into
the kernel.
Setting up a VxVM root disk and mirror
To set up a VxVM root disk and a bootable mirror of this disk, use the
vxcp_lvmrootutility. 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
119Administering disks
Rootability