Introduction To Linux Flashcards
What does Unix refer to?
Linux and “Linux-like” operating systems
Why are Linux systems the most common target for attackers
96.3% of the top one million web servers are running Linux
What is FOSS
Free Open Source Software
What is a Distribution (Distro)
Special-purpose variants of the operating system
Who is the Ubuntu distro geared towards
General-purpose users
Who is the Kali Linux distro geared towards
Specifically designed for security professionals
Command-line only machines are called
Headless servers
Which distro is best suited for a Central Data Server
Fedora and CentOS
Which distro is best suited for a Public Web Server
Ubuntu and Fedora
Which distro is best suited for an IT Audit Workstation
Kali Linux
Which distro is best suited for a User Workstation
Ubuntu
What is SELinux
SELinux has a built-in file permission security enhancement developed by the NSA
CentOS and Fedora have it implemented by default
Which version of Ubuntu Servers do you choose if you are looking for a version that will remain stable over time?
LTS version
‘Long Term Support’s
The LTS version will remain stable and only change appropriately once a year
What is the Linux directory that contains every other folder
/ (root)
What is the directory that contains the user’s private files
/home
(Users should not be able to save files elsewhere)
What directory contains configuration files
/etc (pronounced ‘etsy’)
Configuration files, define how a machine runs and who can use it
Which directory contains main Binary or Program files?
/bin and /sbin
Bin for user programs
Sbin for admin programs
What directory contains files that change over time
/var
Which directory contains files that are only needed for a short period of time
/tmp
What is a Process
A running program is called a process
When a program runs, it must process data and potentially make changes to the file system. This is why a running program is called a process
When these programs process, save and modify data, they consume a computer’s resources.
What is Memory
The space used by a process to save and manipulate data
What 2 forms does memory come in?
1) RAM (Random Access Memory) : Used to run the program’s code. RAM is only used while the program is running.
The more work a process does, the more RAM it needs.
2) Disk Space: used to save data permanently
Files saved to a disk persist even after a process ends
What is the role of the CPU?
The Central Processing Unit acts as the brain of the system, determining how much work a process has to do, and how difficult that work is.
What is a DoS attack doing?
Denial of Service Attacks - attackers perform a DoS attack by launching processes that eat up memory on a target machine.
This can slow down or crash the machine, making it unavailable to the users, thus denying them service
