2.What is BIOS?
Basic Input/Output System
In computing, BIOS is firmware used to perform hardware initialization during the booting process, and to provide runtime services for operating systems and programs.
The BIOS firmware comes pre-installed on a personal computer’s system board, and it is the first software to run when powered on.
Storage Attachment
Computers access disk storage in two ways. One way is via I/O ports (or host-attached storage);
this is common on small system. The other way is via a remote host in a distributed file system;
this is reffered to as network-attached storage.
What is RAID?
RAID stands for Redundant Array of Inexpensive Disks. That means that RAID is a way of logically putting multiple disks together into a single array. The idea then is that these disks working together will have the speed and/or reliability of a more expensive disk. It allows us to store data across multiple hard drives.
The purpose of RAID is to achieve data redundancy to reduce data loss and, in a lot of cases, improve performance.
GNU GRUB : GRUB is extremely easy to install and setup, often requiring only two standard commands. This Linux bootloader is very much filesystem aware and can detect kernel files even without a specified logical sector. GRUB has in-built support for UEFI mainboards, secondary hard-disk drives, most Windows systems, and multiboot. It supports numerous filesystems including but not limited to ext2, ext3, ext4, btrfs, zfs, minix, iso9660, xfs, NTFS, and FAT32.
rEFInd : rEFInd comes with default support for launching legacy BIOS boot loaders on UEFI machines with CSM support. This bootloader allows users to customize the fonts, icons, and backgrounds of their themes as they like. It provides users the ability to set OS-specific boost options and includes ready-made drivers for the Linux ReiserFS and ext2 filesystems. rEFInd is written using the C programming language and is immensely lightweight at only 4 MB.
Clover Bootloader : Clover comes with native support for widescreen GUI and allows users to run EFI commands from the GUI directly. It features stunning themes and icons alongside the ability to customize each component based on the user’s taste. Clover Bootloader offers a wide range of convenient keyboard shortcuts, which makes it extremely easy to administer. Users can directly boot using UEFI firmware or via the CloverEFI firmware emulation.
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Bootloaders
A bootloader is a specific piece of code that will always run whenever an operating system is being started.
Every operating system will have a set of bootloaders specific for it that will always run before the operating system is allowed to run.
It will usually contain several ways in which the operating system kernel can be booted and commands to debug and modify the kernel environment.
Difference Between UEFI and BIOS?
UEFI enables users to handle drives that are larger than 2 TB, while the old legacy BIOS couldn’t handle large storage drives.
UEFI supports more than 4 primary partitions with a GUID Partition Table.
What is a firmware?
Firmware is the low-level software operating the hardware of a microprocessor- or microcontroller-based device. It enables components to interact with each other and implements communications protocols, among other tasks.
Firmware, which is added at the time of manufacturing, is used to run user programs on the device and can be thought of as the software that allows hardware to run.
Examples of firmware include:
Systemd provides a standard process for controlling what programs run when a Linux system boots up. While systemd is compatible with SysV and Linux Standard Base (LSB) init scripts, systemd is meant to be a drop-in replacement for these older ways of getting a Linux system running.