Linux commands

command -parameter+argument

touch --> creates a file(touch afile)

echo linux > afile --> type a text to target file

cat -->shows the content of the mentioned file(cat afile)

echo dontoverwrite >> afile (> overwrites, >> does not overwrite)

head --> first 8 rows

tail --> last 8 rows

more --> read line by line by pressing enter(press Ctrl+C to break more)

pwd --> where I am exactly?

ls --> shows the content of the folder you are in

ls - ln --> shows the content of the entire directory with the permission rights

cd --> jump upper level

cd +arg --> jump to folder arg


mkdir +arg --> creates a new folder named arg


rmdir +arg --> deletes the folder arg(same as command: rm)

cp --> copy a file(cp sourceFile targetFileWithNewName)
cp -r --> copy a folder(cp -r sourceFolder targetFolderWithNewName)

mv --> cut a file(mv file targetFolder)
mv --> addition of cur functionality, also changes the name of a file(mv file newName)

find --> search function. (find Folder)

locate  --> same as find command.

man --> manual for the commands(man grep)

help --> similar with the man.(grep --help)

grep --> find for a spesific pattern in a file
touch grepsample
echo test > grepsample
echo test2 >> grepsample
cat grepsample
cat grepsample | grep 2


useradd -m -g groupname -G othergroupnames -s shell username --> add new user
useradd -m -g users -G audio, video -s /bin/bash lorem

cat /etc/group --> shows user groups


ls - ln --> shows the content of the entire directory with the permission rights

chmod -7 fileName  --> Removes the rights for the current user
chmod -77 fileName --> Removes the rights for the current user group
chmod -777 fileName --> Removes the rights for the others

chmod +7 fileName  --> Gives rights for the current user
chmod +77 fileName --> Gives rights for the current user group

chmod +777 fileName --> Gives rights for the others

1 = execute, 2 = write, 4 = read, 7 total

ps aux --> whole active processes
ps -au(userName) --> active processes for the userName

ps -aux | grep processName --> active processes list which contaion processName

kill -9 processId --> kills process 

killall processName --> kills all processes 

.deb packages

dpkg -i packageName --> install package
dpkg -r packageName --> remove package
dpkg -l --> show installed packages


apt installer

apt update --> updates the package list from repositories
apt apgrade --> upgrades whole packages in your local
apt search packageName --> searchs a package from repository
apt install packageName --> installs a package

apt remove packageName --> removes a package

add apt repository repName --> adds a repository


*---

df --> displays harddisk configurations
fdisk -arg --> harddisk configurations

free --> ram
cat /proc/meminfo --> ram snapshot

vmstat --> CPU
top --> CPU with more details


*---

netstat

netstat -t --> list of tcp connections
netstat -u --> list of udp connections
netstat --route --> route table, gateway, genmask
netstat -s --> network statistics

ifconfig --> network details, ip address, mac, etc.