Physical Storage
The smallest physical storage unit on a disk platter, typically 512 bytes for HDDs.
What is a sector?
The storage area between the end of a file and the end of its last allocated cluster.
What is slack space?
The software process that verifies computer hardware works properly during startup.
What is POST (Power-on Self-Test)?
The legacy version of the bootloader that was replaced by GRUB 2.
What is GRUB (Legacy)?
A computer program that runs as a background process, often named with a trailing 'd'.
What is a daemon?
The concentric circles on platters where data is magnetically recorded.
What are tracks?
The smallest logical storage unit on a hard disk, also known as an allocation unit.
What is a cluster?
The partitioning scheme used by UEFI that supports up to 128 partitions.
What is GPT (GUID Partition Table)?
The full path to the main file used for customizing GRUB2 settings.
What is /etc/default/grub?
The command used to prevent a service from starting entirely.
What is systemctl mask?
A non-volatile storage device that uses NAND flash memory and has no moving parts.
What is a Solid-State Drive (SSD)?
This 512-byte sector is the very first sector ("sector zero") of a data storage device.
What is the Master Boot Record (MBR)?
The initial RAM-based filesystem used to mount the real root filesystem.
What is initramfs?
The command used to regenerate the GRUB configuration file after changes are made.
What is grub2-mkconfig?
The specific systemd target that is equivalent to legacy runlevel 5 (Workstation).
What is graphical.target?
The formula for calculating disk capacity using Cylinders, Heads, and Sectors.
What is Cylinders * Heads * Sectors * 512 bytes?
This data structure in the boot sector describes the physical layout of a volume, like heads and track size.
What is the BIOS Parameter Block (BPB)?
The first process started when booting Linux, serving as the ancestor of all other processes.
What is init?
The directory where scripts for operating system boot menus are stored.
What is /etc/grub.d/?
The systemctl command used to switch to a different target on a running system.
What is systemctl isolate?
The data recording method where tracks are combined into zones based on center distance.
What is Zoned Bit Recording (ZMR)?
FAT file system errors where clusters are marked as used but not linked to any file.
What are lost clusters?
The specific 2-byte signature located at the end of the MBR required by BIOS.
What is the Disk Signature (or Magic Number)?
This script/file is executed at boot time to actually load the Linux kernel.
What is grub.cfg?
The specific runlevel number used by legacy init daemons to reboot a system.
What is Runlevel 6?