l3h dec23

#### on Centos
https://learning.oreilly.com/course/linux-essentials-for/9780137935611/[student@localhost linuxin3hours]$ history
    1  ls
    2  useradd bob
    3  sudo useradd bob
    4  sudo su
    5  sudo -i
    6  nano counter
    7  ls
    8  history
    9  cat countdown
   10  id student
   11  su -
   12  cat countdown
   13  ls -l countdown
   14  chmod +x countdown
   15  ls -l countdown
   16  countdown
   17  echo $PATH
   18  pwd
   19  ./countdown 1
   20  cp countdown /usr/local/bin/
   21  sudo cp countdown /usr/local/bin/
   22  countdown 1
   23  cat countdown
   24  history
   25  sudo dnf install git
   26  git clone https://github.com/sandervanvugt/linuxin3hours
   27  cd linuxin3hours/
   28  ls
   29  which git
   30  history
   31  cat /etc/os-release
   32  ls /home/$USER
   33  ls /home
   34  ls /tmp
   35  ls /usr/bin
   36  ls /usr/bin | wc -l
   37  ls /usr/sbin
   38  ls /etc
   39  cat /etc/os-release
   40  cat /etc/passwd
   41  history
   42  find / -name "hosts"
   43  find / -name "hosts" 2> /dev/null
   44  find / -name "*hosts*" 2> /dev/null
   45  cat /etc/passwd
   46  grep bob /etc/passwd
   47  grep bob *
   48  grep bob /etc/* 2>/dev/null
   49  which countdown
   50  find / -name "countdown" 2>/dev/null
   51  man hier
   52  sudo find / -name "passwd"
   53  sudo find / -name "passwd" 2> /dev/null
   54  history
   55  man -k sander
   56  man -k user
   57  sudo mandb
   58  man -k user
   59  man -k user | wc -l
   60  man -k user | grep create
   61  useradd --help
   62  useradd --help | less
   63  history
   64  man unminimize
   65  man grep
   66  grep --help
   67  grep --help | grep case
   68  countdown 10
   69  ssh student@192.168.29.139
   70  lsblk
   71  sudo umount /dev/sdb1
   72  lsblk
   73  sudo mount /dev/sdb1 /mnt
   74  ls /mnt
   75  echo helloagain > /mnt/helloagain
   76  sudo cp /etc/hosts /mnt/
   77  lsblk
   78  touch /run/media/student/SanDisk/hellofolks
   79  ls -l /run/media/student/SanDisk/
   80  history
   81  umount /dev/sdc1
   82  history

###on Ubuntustudent@student-virtual-machine:~$ history
    1  ps aux
    2  ps aux | grep ssh
    3  sudo apt install openssh-server
    4  ps aux | grep ssh
    5  top
    6  systemctl status sshd
    7  sudo systemctl stop sshd
    8  systemctl status sshd
    9  sudo systemctl start sshd
   10  systemctl status sshd
   11  sudo systemctl disable --now sshd
   12  sudo systemctl status sshd
   13  sudo systemctl status ssh
   14  sudo systemctl stop ssh
   15  sudo systemctl list-unit-files
   16  #sudo systemctl list-unit-files
   17  ps aux | grep ssh
   18  sudo systemctl enable --now ssh
   19  ps aux | grep ssh
   20  pidof sshd
   21  sudo kill $(pidof sshd)
   22  sudo systemctl status ssh
   23  sudo systemctl start ssh
   24  ps aux | grep ssh
   25  sudo top
   26  ip addr show
   27  ifconfig
   28  sudo ufw status
   29  history