Hey there! Here you will find this cheat sheet which I prepared to show, all linux commands which I use to day a day, in my actual role as System Engineer.

Table content

More coming soon! Stay tuned…

Help

Help commands

  • man manual page (wide)
  • whatis short description
  • apropos related help

⇧ back to top

Users👤

Change and info

  • whoami current user
  • su switch to user [root]
  • visudo edit sudoers [vi+sudo]

System users

  • useradd create/update user
    • adduser friendly add user
  • userdel delete user
    • deluser friendly del user
  • usermod modify user account
  • groups group members
  • passwd change password
  • Islogins show known users

Logged users

  • who current logged users
    • w current logged users & data
  • users current logged users
  • last last logged users & reboots
  • lastb last bad logins
  • lastlog recent login users

⇧ back to top

Network🌐

Net configuration

  • ifconfig config ip/net features
    • ip new ifconfig tool
  • dhclient DHCP client

DNS and domains

  • ping send ICMP to hosts
  • nslookup query DNS lookup
    • dig DNS lookup utility
  • whois whois domain name or ip

Trace route

  • traceroute print route packets
  • tracepath trace path
    • mtr network diagnostic tool

Network tools

  • nmap network security scanner
  • nc cat via network connection
  • ss show sockets statistics

Network monitoring

  • bmon bandwidth monitor
  • iftop interface network monitor
  • nethogs net monitor by process
  • wondershaper bandwidth limit
  • Iptraf-ng network monitor
  • tcpdump network activity dump
  • netstat print network statistics

Mac address

  • arp show mac/ip address cache
  • arping ping mac address

Firewall

  • iptables ip packet filter & NAT

    • shorewall firewall for iptables
    • ufw firewall for iptables

    ⇧ back to top

Files-Folders

Folders (Directories)

  • mkdir create dir
    • -p all dirs
  • pwd current dir
  • ls list files & dirs
    • -l long data
    • -h human
    • -R recursive
  • cd change to dir
  • pushd / popd directory stack
  • autojump smart jump to dirs
  • tree list files in tree format

File handling

  • file show file type
  • touch update/create
  • mv move/rename files
    • -f force
    • -u update
  • cp copy files
    • -f force
    • -r recursive
  • rm remove files
  • ln make link to file
  • stat filesytem stats

Fine files

  • type display command type

  • Find search files in a dir

    • locate search files in database
    • updatedb update file database

  • whereis locate binary/manpage

  • which get binary file pathname

    ⇧ back to top

Remote

  • telnet telnet connection
  • ftp file transfer connect
    • ssh remote connection
  • sftp connect ftp via ssh
  • sshfs connect disk via ssh

SCP/SSH SYNTAX

scp user@ip:/folder remote

⇧ back to top

More coming soon! Stay tuned…