Partitioning of Disk on an Appliance

A firmware is a low-level software that is responsible to initialize the hardware components of a system during the boot process. It is required to initialize the boot process. It provides runtime services for the operating system and the programs on the system. There are two types of boot modes in the system setup, Basic Input/Output System (BIOS) and Unified Extensible Firmware Interface (UEFI).

BIOS is amongst the oldest systems used as a boot loader to perform the initialization of the hardware. UEFI is a comparatively newer system that defines a software interface between the operating system and the platform firmware. The UEFI is more advanced than the BIOS and most of the systems are built with support for UEFI and BIOS.

Disk Partitioning is a method of dividing the hard drive into logical partitions. When a new hard drive is installed on a system, the disk is segregated into partitions. These partitions are utilized to store data, which the operating system reads in a logical format. The information about these partitions is stored in the partition table.

There are two types of partition tables, the Master Boot Record (MBR) and the GUID Partition Table (GPT). These form a special boot section in the drive that provides information about the various disk partitions. They help in reading the partition in a logical manner.

The following table lists the differences between the GPT and the MBR.

GUID Partition Table (GPT)Master Boot Record (MBR)
Supported on UEFI.Supported on BIOS. Can also be compatible with UEFI.
Supports partitions up to 9 ZB.Supports partitions up to 2 TB.
Number of primary partitions can be extended to 128.Maximum number of primary partitions is 4.
Runs in 32-bit and 64-bit OS.Runs in 16-bit OS.
Provides discrete driver support in the form of executable.Stores the drive support in its ROM, therefore, updating the BIOS firmware is difficult.
Offers features such as Secure Boot to limit the initialization of boot process using unauthorized applications.Boots in the normal mode
Has a faster boot time.Has a standard boot time.

Depending on the requirements, you can extend the size of the partitions in a physical volume to accommodate all the logs and other appliance related data. You can utilize the Logical Volume Manager (LVM) to increase the partitions in the physical volume. Using LVM, you can manage hard disk storage to allocate, mirror, or resize volumes.

In an appliance, the physical volume is divided into the following three logical volume groups:

PartitionDescription
BootContains the boot information.
PTYVGContains the files and information about OS and logs.
Data Volume GroupContains the data that is in the /opt directory.