User Management (Buster)

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At best, there's me, and one or two people I'm training, who actually have shell access.

So I make my user settings pretty global.

Users and Groups

Some of this stuff is discussed in various relevant sections as well.

addgroup --gid 70 wheel
addgroup --gid 72 hugepager
addgroup --gid 74 website
addgroup --gid 900 vmail
grpck -s
useradd -d /var/vmail -s /usr/sbin/nologin -g 900 -r -u 900 vmail
usermod -a -G adm,cdrom,audio,src,staff,games,users,wheel adminusernamehere
usermod -a -G wheel root

Adding wheel to root is necessary for later security measures.


I add:

# Enable completion
shopt -s globstar
shopt -s histappend
# There is a point at which either just typing it
# again or looking through the file is more productive...

Bash completion is provided through /etc/profile.d/ so no need to uncomment.


# Colors and aliasing
# Prefer to set this up as an 'include' instead. Easier to make
# alias changes that I may be using across a large number of accounts.
# Check for interactive bash
[ -z "$BASH_VERSION" -o -z "$PS1" ] && return
if [ -x /usr/bin/dircolors ]; then
    test -r ~/.dircolors && eval "$(dircolors -b ~/.dircolors)" || eval "$(dircolors -b)"
    alias ls='ls --color=auto -A'
    alias l='ls --color=auto -la'
    alias ls='ls -A'
    alias l='ls -la'

Default /etc/skel

mkdir /etc/skel/.ssh
mkdir /etc/skel/bin
touch /etc/skel/.ssh/authorized_keys /etc/skel/.toprc /etc/skel/.viminfo /etc/skel/.bash_history
chmod 640 /etc/skel/.bash_logout /etc/skel/.bashrc /etc/skel/.profile /etc/skel/.toprc /etc/skel/.ssh/authorized_keys /etc/skel/.viminfo /etc/skel/.bash_history
chmod 750 /etc/skel/.ssh/ /etc/skel/ /etc/skel/bin

I also add my own public key to authorized_keys here.


RCfile for "top with windows"           # shameless braggin'
Id:a, Mode_altscr=0, Mode_irixps=1, Delay_time=0.500, Curwin=2
        winflags=64808, sortindx=0, maxtasks=0
        summclr=1, msgsclr=1, headclr=3, taskclr=1
Job     fieldscur=ABcefgjlrstuvyzMKNHIWOPQDX
        winflags=64825, sortindx=0, maxtasks=0
        summclr=6, msgsclr=6, headclr=7, taskclr=1
Mem     fieldscur=ABGCNOPQRSTUVdefJlMyzWHIKX
        winflags=64808, sortindx=2, maxtasks=0
        summclr=2, msgsclr=1, headclr=6, taskclr=1
Usr     fieldscur=ABDECGfhijlopqrstuvyzMKNWX
        winflags=62777, sortindx=4, maxtasks=0
        summclr=3, msgsclr=3, headclr=2, taskclr=3

I am addicted to my personal top settings.


After removing unnecessary stuff it looks more like:

# ~/.bashrc: executed by bash(1) for non-login shells.
# see /usr/share/doc/bash/examples/startup-files (in the package bash-doc)
# for examples
# If not running interactively, don't do anything
case $- in
    *i*) ;;
      *) return;;
# Alias definitions.
# You may want to put all your additions into a separate file like
# ~/.bash_aliases, instead of adding them here directly.
# See /usr/share/doc/bash-doc/examples in the bash-doc package.
if [ -f ~/.bash_aliases ]; then
    . ~/.bash_aliases
# Get your fortune cookie!
# Place here so user can nuke/edit as desired.
# Probably should fix cowsay to handle line breaks better.
if [ -f /usr/games/fortune ]; then
  if [ -f /usr/games/cowsay ]; then
    /usr/games/fortune -a | /usr/games/cowsay -W 75 -p
    /usr/games/fortune -a


While I copy other skeleton files to root/admin users, a separate .bashrc file is nice even if some of the reason for it is legacy. The talking cow does get a bit annoying bouncing in and out of root all the time.

# ~/.bashrc: executed by bash(1) for non-login shells.
#When restarting mysql, the memlock value gets taken from root's limits, so if we
#are more restrictive, hugepage allocation will fail.
ulimit -l 134217728
ulimit -n 1048576
# If not running interactively, don't do anything further
case $- in
    *i*) ;;
      *) return;;
# Alias definitions.
# I like using nologin for most users, but this can make maintenance difficult, so...
alias sub="su -s /bin/bash"
# You may want to put all your additions into a separate file like
# ~/.bash_aliases, instead of adding them here directly.
# See /usr/share/doc/bash-doc/examples in the bash-doc package.
if [ -f ~/.bash_aliases ]; then
    . ~/.bash_aliases


A web skeleton file to help simplify site deployment.

cp -R /etc/skel /etc/webskel
mkdir /etc/webskel/pool
mkdir /etc/webskel/docs
mkdir /etc/webskel/priv
mkdir /etc/webskel/sock
chmod 750 /etc/webskel/pool /etc/webskel/docs /etc/webskel/priv /etc/webskel/sock
  • /etc/webskel/.ssh/authorized_keys
    • add no-agent-forwarding,no-port-forwarding,no-pty,no-user-rc,no-X11-forwarding before ssh-rsa for each key, as well as when you add user keys.
cp /etc/adduser.conf /etc/webuser.conf
  • /etc/webuser.conf:
    • DSHELL=/usr/sbin/nologin
    • SKEL=/etc/webskel

User adding scripts

Because it's all about typing fewer characters.


# This is for adding other administrative users, special
# accounts (e.g. for minecraft or git) and so on.
if [ $1 ] ; then
  /usr/sbin/adduser --gecos "" $1
  /bin/chmod 0750 /home/$1
  echo "Usage: username"


# This still doesn't do everything it should. Need to flesh it out more.
if [ $1 ] && [ $2 ] && [ $3 ] ; then
 export KEYFILE="/etc/certs/$2.key"
 export CSRFILE="/etc/certs/$2.csr"
 /usr/bin/openssl genrsa -out $KEYFILE 4096
 /bin/chmod 0600 $KEYFILE
 /bin/sed -e "s/DOMAIN/$2/g" /root/csr.cnf > /root/csr$2.cnf
 /usr/bin/openssl req -new -config /root/csr$2.cnf -key $KEYFILE -out $CSRFILE
 /usr/sbin/adduser --shell /usr/sbin/nologin --disabled-password --gecos "" --conf /etc/webuser.conf $1
 /usr/sbin/usermod -a -G website $1
 /usr/bin/mkdir /var/log/$2
 /bin/chmod 0750 /var/log/$2
 /bin/chown $1:$1 /var/log/$2
 /usr/bin/ln -sv /var/log/$2 /home/$1/logs
 /bin/sed "s/USERNAME/$1/g; s/DOMAIN/$2/g; s/IPADDRESS/$3/g" /root/fpmnginx.conf > /etc/nginx/sites/$1.conf
 /bin/sed "s/USERNAME/$1/" /root/fpmpool.conf > /home/$1/pool/$2.conf
 /bin/chmod 0751 /home/$1
 /bin/chown root /home/$1
 /bin/chown root /home/$1/.ssh
 /bin/chown root /home/$1/.ssh/authorized_keys
 /bin/chgrp www-data /home/$1/docs
 /bin/chgrp www-data /home/$1/sock
#  /usr/bin/systemctl restart php7.3-fpm
 echo "Usage: username domain ipaddress"

This makes use of the templates we make in other parts of the guide, applying them accordingly.

While the nginx config is connected to fpm properly, you still need to assign an IP address and call it.