Data that is not critical for booting the system is only accessed by VxVM after the system is fully operational, so it does not have to be located in specific areas. VxVM can find it. However, boot-critical data must be placed in specific areas on the bootable disks for the boot process to find it.
On some systems, the controller-specific actions performed by the disk controller in the process and the system BIOS constrain the location of this critical data.
If a boot disk fails, one of the following procedures can be used to correct the problem:
If the errors are transient or correctable, re-use the same disk. This is known as re-adding a disk. In some cases, reformatting a failed disk or performing a surface analysis to rebuild the alternate-sector mappings are sufficient to make a disk usable for re-addition.