Linux commands - eitan-j/tech-journal GitHub Wiki

whoami shows current user
sudo -i to become root
sudo [executable] to run [executable] as root
passwd [user] to change password of [user]
- leave blank for current user
useradd [user] to create new [user]
userdel [user] to delete [user]
- add -r to delete user dir also
groupadd [group] to create [group]
groupdel [group] to delete [group]
usermod -aG [group] [user] to add [user] to group]
- -aG for append Group
chgrp [group] [file] to change [file] to [group]
chown [user]:[group] [file] to change [file] ownership to [user]
- [group] is optional
chmod [who][what][which] [dir]
- The [who][what][which] can be repeated with a comma in between
- [who] is who you will apply this to
  - Options are u for user (owner), g for group, o for other, and a for all
    - Multiple can be used at once
- [what] is what to do
  - - to remove, + to add, = to overwrite
- [which] is which permissions to change
  - r for read, w for write, x for execute
    - Multiple can be used at once
- [who][what][which] can be replaced with [owner][group][other]
  - Each of these is a single digit base 10 representation of a three digit base 2 number
    - The first bit is for read, second is for write, third is for execute

apt install [program] installs [program] (Debian based)
- adding -y to the end auto accepts any prompt

ftp addr
option -i "Turns off interactive prompting during multiple file transfers."
- Not sure if this is relevant
put [file] to put [file]
ls lists files and folders
get [file] to get [file]
passive to enter passive mode
- passive mode makes all inbound traffic to port 21