Install vim:

apt install -y vim

customize ~/.vimrc for root und administrator (or main user). To paste via PuTTY into a ViM window, you have to add set mouse-=a first.

syntax on
set laststatus=2
set nobackup
colorscheme elflord
set hlsearch
set mouse-=a
"auto jump to the line where closed
if has("autocmd")
  au BufReadPost * if line("'\"") > 0 && line("'\"") <= line("$")
    \| exe "normal! g'\"" | endif
endif

~/.bashrc (root)

PS1='\[\e[1;31m\]\u@\h:\[\e[0;33m\]\w\$\[\e[0;37m\] '
export LC_COLLATE="C"
export LS_OPTIONS='--color=auto --group-directories-first'
eval "`dircolors`"
alias ls='ls $LS_OPTIONS'
alias ll='ls $LS_OPTIONS -l'
alias l='ls $LS_OPTIONS -lA'
alias grep='grep --color'

Administrator .bashrc, uncomment:

force_color_prompt=yes

Add at the end at " some more ls aliases"

export LC_COLLATE="C"
export LS_OPTIONS='--color=auto --group-directories-first'
eval "`dircolors`"
alias ls='ls $LS_OPTIONS' 
alias ll='ls $LS_OPTIONS -l'
alias l='ls $LS_OPTIONS -lA'

Install/configure some stuff

apt install -y zip bash-completion
dpkg-reconfigure keyboard-configuration

Enable bash-completion /etc/bash.bashrc (uncomment)

# enable bash completion in interactive shells
if ! shopt -oq posix; then
  if [ -f /usr/share/bash-completion/bash_completion ]; then
    . /usr/share/bash-completion/bash_completion
  elif [ -f /etc/bash_completion ]; then
    . /etc/bash_completion
  fi
fi

Install secure-delete and use srm

apt install secure-delete
srm file.txt

If you want to RSYNC through SSH and there are probably a lot of data, then use following steps:

Install screen, so you can exit your SSH session during rsyncing.

Open scren:

screen

Start a rsync from remote to your local dir:

rsync -av -e ssh username@ipadressordns:/remote/his/folder /home/my/folder/ > rsync.log 2>&1

after you started this, use CTRL+Z and with the command bg you make sure, the command is running in the background.
now you can use tail, to stalk the progress of the sync

tail -f rsync.log




If you have a different SSH port use this

rsync -av -e "ssh -p 2121" username@ipadressordns:/remote/his/folder /home/my/folder/

you can leave the screen with CTRL+A then D and you can exit the SSH connection and go having a beer.
The next day you can look at your syncing with:

#resume screen from day before
screen -r

#put sync command in foreground (if it is still running)
fg

#check sync file
vim rsync.log

#start another sync like above, to make sure, everything was synced correctly

helpful: http://troy.jdmz.net/rsync/index.html

Source: https://unix.stackexchange.com/a/194058/223965

Two days back:

journalctl --vacuum-time=2d

Retain only the past 500 MB:

journalctl --vacuum-size=500M

To get the checksum of a string, use this.

echo -n "yourstring" |md5sum
echo -n "yourstring" |sha1sum
echo -n "yourstring" |sha256sum

source Stackoverflow