Boot disk structure on Integrity servers
The boot disk/disks of every Integrity server are divided into three partitions:
- EFI Partition: Contains the necessary tools and files to find and load the appropriate kernel. Here resides for example the hpux.efi utility.
- OS Partition: In the case of HP-UX contains the LVM or VxVM structure, the kernel and any filesystem that play a role during the boot process.
- HP Service Partition (HPSP).
The Extensible Firmware Interface (EFI) partition is subdivided into three main areas:
- MBR: The Master Boot Record, located at the top of the disk, a legacy Intel structure ignored by EFI.
- GPT: Every EFI partition is assigned a unique identifier known as GUID (Globally Unique Identifier). The locations of the GUID s are stored in the EFI GUID Partition Table or GPT. This very critical structure is replicated at the top and the bottom of the disk.
- EFI System Partition: This partition contains the OS loader responsible of loading the operative system during the boot process. On HP-UX disks the OS loader is the famous \efi\hpux\hpux.efi file. Here is contained also the \efi\hpux\auto file which stores the system boot string and some utilities as well.
The OS Partition obviously contains the Operative System that runs on the server. An HP-UX partition contains a LIF area, private region and public region.
The Logical Interchange Format (LIF) boot area stores the following files:
- ISL. Not used on Integrity.
- AUTO. Not used on Integrity.
- HPUX. Not used on Integrity.
- LABEL. A binary file that contains the records of the locations of /stand and the primary swap.
The private region contains LVM and VxVM configuration information.
And the public region contains the corresponding volumes for:
- stand: /stand filesystem including the HP-UX kernel.
- swap: Primary swap space.
- root: The root filesystem that includes /, /etc, /dev and /sbin.
HP Service Partition
The HP Service Partition, or HPSP, is a FAT-32 filesystem that contains several offline diagnostic utilities to be used on unbootable systems.