Kahoots - LINUX
Contains everything needed for the boot process
/boot
Contains special or devices files
/dev
Host-specific system configuration files
/etc
Where are all system cron jobs stored
/etc/crontab or /etc/cron.d
What file is referenced by default during Name Resolution
/etc/hosts
Location of startup scripts (sysV)
/etc/init.d
What file is referenced to determine host name resolution method
/etc/nsswitch.conf
File that sets the PATH variable
/etc/profile
What file is reference when setting default dns server ip addresses
/etc/resolv.conf
What is the primary log configuration file in SysV
/etc/rsyslog.conf
Which file stores a list of available shells
/etc/shells
Essential shared libraries and kernel modules
/lib
Kernel and process information virtual filesystem
/proc
What number is associated with /dev/stdin
/proc/self/fd/0
What number corresponds to /dev/stdout
/proc/self/fd/1
What number corresponds to /dev/stderr
/proc/self/fd/2
Essential system administration binaries
/sbin
Contains binaries, libraries, documentation, and source-code
/usr
Administrative files such as log and spool files
/var
Which is a typical location for logs
/var/log
Contains information on failed login attempts
/var/log/btmp
Maintains the logs of all logs of all logged in and logged out users (in the past)
/var/log/wtmp
Contains information about users who are currently logged onto the system
/var/run/utmp
If you copied a files from a Linux machine to a Windows machine, what would be true?
The files hashes will be the same
Which is a reason that root wouldn't be able to delete, move, or change a file
The immutable attribute bit is set on the file
What is the output for : echo "one two three four" | sed 's/one/two/'
two two three four
Command that indicates how a command will be interpreted at the command line
type
What does the ctime timestamp most accurately monitor
when file contents were modified or permissions were changed
A daemon process
will always be an orphan
This type of variable is only available to the process in which it was defined
Local
Interactive shell created when authenticating into machine
Login Shell
Contains the primary bootloader, partition table and MBR validity check
MBR
What type of socket is used when utilizing a packet sniffing program
raw sockets
Text, image, binary, compressed, shared libraries, etc...(file-type)
regular file
Expands to the process ID of the shell
$$
Identify the correct Arithmetic Expansion Syntax
$((4+5))
Identify the correct Command Substitution Syntax
$(echo Hello)
Expands to the current option flags as specified upon invocation
$-
Expands to the name of the shell or shell script
$0
Expands to the exit status of the most recently executed foreground pipeline
$?
What is the correct syntax to prevent the substitutions from happening
'$(cat $AFILE)'
Running as root, what would this output: echo $EUID
0
What is the output of: A=1; B=1; echo $A + $B + $(($A+$B))
1 + 2 + 3
What is the output of: A=1; B=2; echo $A + $B + $(($A+$B))
1+2+3
How many bytes are in an MD5 hash?
16
How many bytes are in each partition [in the MBR]
16
What is the syntax to redirect STDERR
2>
How many characters are in an MD5 hash?
32
How many primary partitions are there in the MBR
4
When is this cron job running: 12 4 * * * /usr/bin/backup
4:12AM
Number of bytes in the MBR
512
What generates Authentication logs
All attempts at accessing the system via configured login
What generates System logs
Any actions taken by the Kernel
A software generated event creates a ___ log
Application
What commands will get you help
Apropos Help Man
Reads and executes the first sector on the boot disk (MRB) to load the bootloader to memory
BIOS
What is the correct order for the Linux Boot Process
BIOS, MBR, GRUB, Kernel, Init, Runlevel
What type of socket requires root privilege to be created
Both Raw sockets and regular sockets < 1024
What is this called, and what is its output: echo {a..e}
Brace Expansion: a b c d e
What is this called, and what is its output: {a..e}
Brace Expansion; a b c d e
Defines the access rights for a process
Effective User ID (EUID)
What does the BIOS do during the Linux boot process
Executes the boot loader program and POST
True or False: Hashes from two different files can never match?
FALSE
syslog/rsyslog messages are labeled with what, and assigned a what?
Facility Code.Severity Level
Boolean result of: true XOR true
False
Commands like 'nslookup' check the /etc/hosts file before checking DNS
False
journald's log is persistent by default
False
Configurable Bootloader sets default OS and kernel parameters
GRUB
This type of variable will be available to all children of the process in which it was defined
Global
What is it called when hashes from two different files are exactly the same
Hash collision
Configures the environment for the system / runs startup scripts
INIT
What attributes are being set on the file: chatter +ia file.txt
Immutable and Append only
Reads commands from user input on a terminal
Interactive Shell
Establishes Memory, Management, Drivers, Mounts Filesystem
Kernel
What does the mtime timestamp monitor
Last time the file contents were modified
What is 'iptables'
Linux Firewall
What is SAMBA
Linux program to provide shares to Windows systems
What will the REGEX [0-9]{1,3} do?
Match any digit 1 to 3 times
What will the REGEX [a-zA-Z] do?
Matches a single character of any case
What is mtime? (file timestamp)
Modify time
Shell not requiring the start of /etc/profile because no remote authentication is completed
Non-Login Shell
Type of shell used when a script is run
Non-interactive Shell
What are the two methods to change Linux file permissions
Octal and Relative
Defines which user can kill and send signals to a process
Real User ID (RUID)
Which type of socket requires root privileges and obeys the Protocol stack
Regular Sockets < 1024
Determines mode that the OS will run in (GUI, Command Line Only, etc..)
Runlevel
Single user mode is what runlevel
Runlevel 1
Multiuser, without networking is what runlevel
Runlevel 2
Full multiuser mode with networking is what runlevel
Runlevel 3
X11 (GUI), is what runlevel
Runlevel 5
Syslog and rsyslog are pertaining to which system
SysV
True or False: grep -E will give you the same results as egrep
TRUE
What is notable about raw sockets
They bypass the kernel networking stack to access the NIC
What is the output for Var=15; echo VAR
VAR
Returns the pathname of the file(link) that would be executed in the current environment
Which
What identifies a kernel mode process on a 'ps' output
[brackets] or PPID of 2 (kthreads)
A zombie process is
a completed child process waiting on its parent
A zombie process is also known as
a defunct process
What is atime? (file timestamp)
access time
An orphan process is
adopted by init after its parent dies
A good/bad login attempt creates a ___ log
authentication
Provide buffered access to system hardware components (file-type)
block device file
Which command would NOT take you to your home directory
cd /usr
What is ctime? (file timestamp)
change time
What command is used to change file permissions
chmod
What does exec 3<>/dev/tcp/google/80 do?
creates a TCP socket
Edits user's crontab contents
crontab -e -u [user]
Displays the user's crontab contents
crontab -l -u [user]
Removes the user's crontab contents
crontab -r -u [user]
Sets the user'swhat command is used crontab file to the contents of a listed file
crontab -u [user] file
Displays the working environment variables
env
Replaces current process with new program's process
exec Open Paren/Close Paren
What is the Kernel's job during the Linux boot process
execute /sbin/init
Command that determines file type
file
Copies a parent process before making a child process for a new program
fork ()
Which is NOT a DNS troubleshooting command
grep
Displays previous commands and their locations
hash
Config File for /sbin/init (sysV)
inittab
Append a rule to iptables
iptables -A INPUT -j ACCEPT -s 192.168.0.23
Delete rule from iptables
iptables -D OUTPUT 2
Insert a rulet to iptables
iptables -I INPUT -j ACCEPT -s 192.168.0.23
Display current iptables rules
iptables -L -v
What are some features of BASH
job control, command history, tab completion
Which systemD command concerns logs
journalctl
Which command will read the binary file
last -f /var/log/btmp
What does the atime timestamp monitor
last time the file contents were displayed
Reference to another file on the system (file-type)
link file
What is a partition
logical subdivision of physical media
Which command is related to automatically managing logs
logrotate
Which is true concerning log formats
logs can be in ASCII or binary formats
What command shows a file's attributes
lsattr
What command will list all the open files on the system
lsof
Built in reference materials for commands and functions
man
Config File for GRUB (sysV)
menu.lst
What does the 'grep' command do
prints lines containing a matching pattern
What is this cron job doing? 15 * * * 0 /user/bin/backup
running every hour on the 15 minute mark on Sunday
What is the ancestor process of all user mode processes
sbin/init
Changes the value of a shell option or display the names and values of shell variables
set
Which is not a Linux logging category
shutdown
Provide a means of interprocess communication (file-type)
socket or pipe file
What is NOT a feature of BASH
spell check
Which command establishes an ssh connection
ssh [email protected] , exec 7<>/dev/tcp/localhost/ssh , nc localhost 22
A kernel generated event creates a ___ log
system
What command is used by SystemD to configure units
systemctl
An alias has to be the first word in the command and in an interactive shell, true or false
true
Boolean Result of true XOR false
true
Boolean Result of: true AND true
true
Boolean Result of: true OR false
true
File that usually sets persistent aliases for a specific user
~/.bashrc