HP OpenVMS 8.x Or more blocks. For example, $ DUMP/HEADER/BLOCK=END=0 SYS$SYSDEVICE000000GPT.SYS

NOTE: If the target OpenVMS I64 system disk has an incorrectly-placed [000000]GPT.SYS file, the disk cannot be used reliably as an OpenVMS I64 system disk. Typically, the file gets incorrectly placed due to the use of an older version of BACKUP/IMAGE, a file-based BACKUP disk restoration, or an errant disk defragmentation tool (the file is set with /NOMOVE to disable move operations; defragmentation tools that do not honor this setting will corrupt the file). A correctly-located GPT.SYS file will have at least two file extents, the first beginning at LBN 0 and the last at the disk capacity minus the size of the last extent (an extent is one or more adjacent clusters allocated to a file). The size of each of the two extents varies according to the disk cluster factor on the target disk. The first extent size is currently 34 or more blocks, and the last extent

33 or more blocks. For example:

$ DUMP/HEADER/BLOCK=END=0 SYS$SYSDEVICE:[000000]GPT.SYS ...

Map area

Retrieval pointers:

Count: 36 LBN: 0

Count: 36 LBN: 71132925

This example is from a disk with 71132960 blocks. The placement of the final extent is 71132924, which is calculated by subtracting 36 (the size of the last extent) from the disk capacity (71132960).

You may be able to temporarily recover from this condition and attempt to bootstrap the target OpenVMS I64 system disk by renaming GPT.SYS to GPT.BAD, and then entering the SET BOOTBLOCK command. To correctly recover from this condition, you must INITIALIZE the target disk and then reload the disk contents using a file-based BACKUP restoration or a file-based COPY operation. No supported means exists for adding a GPT.SYS file onto an existing disk nor for adding the file during a BACKUP/IMAGE restoration operation.

To write the boot block structures onto an OpenVMS I64 system disk, enter the SET BOOTBLOCK command using the following format:

$ SET BOOTBLOCK [/PRESERVE=SIGNATURES] [/I64] [boot-partition-name]

You can specify the file name for the boot partition (boot-partition-name). If you do not specify a file or device name, the command defaults to the following file for the boot partition:

SYS$SYSDEVICE:[VMS$COMMON.SYS$LDR]SYS$EFI.SYS

The command also assumes the current architecture. To specify OpenVMS I64, include /I64 in the command line.

Use the /PRESERVE=SIGNATURES qualifier to preserve the existing GUID disk signature value and the associated root aliases. Note that using the OpenVMS Backup utility creates a new disk signature when restoring a bootable disk image.

If you reset the boot block structures, you might need to remove any EFI boot aliases that reference the disk, and then add them back again. You can use the EFI alias command to remove and add aliases; HP recommends using the OpenVMS I64 Boot Manager utility (SYS$MANAGER:BOOT_OPTIONS.COM) to maintain EFI console boot aliases.

NOTE: The boot partition file must be contiguous and movefile operations on the file must be disabled. If the file is not contiguous, use the DCL command COPY/CONTIGUOUS (or equivalent) to re-create a contiguous version of the file. To disable movefile operations, use the DCL command SET FILE/NOMOVE. This prevents bootstrap failures that could result from the normal and expected operations of disk defragmentation tools.

Alternatively, you can write a boot block by entering the following command:

$ RUN SYS$SYSTEM:SYS$SETBOOT

The utility prompts you for the required input (in a way similar to the operation of the OpenVMS Alpha Writeboot utility).

A.5 Configuring and Managing OpenVMS Booting on Integrity Servers 171