Category Archives: Linux

Linux Fundamentals Notes

Here are some more notes as you prepare for the latest version of the Linux+ exam.

Controlling Hardware in Linux 

  • Linux actually refers to the kernel (core OS component)
  • The BIOS/UEFI starts the boot loader which starts the operating system kernel of Linux
  • The kernel coordinates actions between the hardware and the software
  • It runs in ring zero or often called kernel space
  • The user space tends to refer to everything out of the kernel space
  • The Linux kernel is tasked with driving the hardware in use
  • It exports data about the detected hardware using the /sys and /proc virtual file systems
  • Applications often access devices using the files created in /dev; specific files represent specific devices, for example: 
    • Disk drive – /dev/sda
    • Partition – /dev/sda1
    • Mice – /dev/input/mouse0
    • Keyboards – /dev/input/event0
    • Sound card – /dev/snd/*
    • Serial ports – /dev/ttyS*
  • You can tell which type of file you have (block versus character) when you list the files – note the use of the b or c character in the ls output

CompTIA Linux+ XK0-005 Study Notes 1.1 FHS

Hello everyone – CompTIA was gracious with an exam voucher for my Linux+ exam so I am sharing my study notes here for all. Enjoy!

1.0 System Management

1.1 File Hierarchy Standard (FHS)

/boot – boot loader files

/proc – virtual filesystem for processes and kernel information as files

/sys – information about devices, drivers, and kernel features

/var -variable files that will change; e.g. logs

/usr – read-only user data

/lib – libraries that are essential to bin directory binaries 

/ dev – device files

/etc – host specific system-wide configuration files

/opt – add-on app software packages

/bin – essential command binaries ; e.g. Is

/sbin – essential system binaries; eg. init

/home – users home directories

/media – mount points for removable media

/mnt – temporarily mounted filesystems

/root – home directory for the root user

/tmp – directory for temporary files