Add languages to PHP Docker Container

Recently I have noticed that the output of the following code shows the month in the wrong language (English instead of German):

setlocale(LC_ALL, 'de_DE.utf8');
$date_now = date('Y-m-d');
echo strftime('%B %Y', strtotime($date_now));

This can be solved by installing the required language in the docker container. Unfortunately there is a bug which prevents that the languages can be easy activated by locale-gen <lang-code>. So you have to enable them in /etc/locale.gen first and then generate them with locale-gen. This code solves the problem:

FROM php:7-apache


# install localisation
RUN apt-get update && \
    # locales
    apt-get install -y locales

# enable localisation and generates localisation files
RUN sed -i -e 's/# de_DE ISO-8859-1/de_DE ISO-8859-1/' /etc/locale.gen && \ # to uncomment the lange
    sed -i -e 's/# <your lang code from locale.gen>/<your lang code from locale.gen again>/' /etc/locale.gen && \


Or you could install all available languages:

FROM php:7-apache


# install localisation
RUN apt-get update && \
    # locales
    apt-get install -y locales locales-all


If you perform a dry run in the container, you must restart Apache for see the changes.

Preparing a Root-Server and install Docker-CE

This is my personal note list for preparing a root server. The list is not complete and may contain errors.

Network setup

  • Install OS as usual or use image from Control Panel

Network setup

  • Set/check fixed ip
  • Set the “Reverse DNS” entry in Control Panel
  • Add local user
    useradd <username>
    usermod -aG sudo <username>
  • Set hostname
    sudo hostnamectl set-hostname <hostname>
  • Edit the /etc/hosts file
  • Edit the /etc/cloud/cloud.cfg file if exists (preserve_hostname: false to true)


  • Add pubkey to ~/.ssh/authorized_keys
  • Disable SSH login with password and permit root login in /etc/ssh/sshd_config file
PasswordAuthentication no
PubkeyAuthentication yes
PermitRootLogin prohibit-password
  • Restart SSH Daemon
    service sshd restart


  • VIM Color open ~/.vimrc and add
    colo desert
    syntax on


  • Install docker-cd here
  • Install docker-compose here
  • Install docker-compose command completion here
  • add username to docker group (source)
    sudo usermod -aG docker $USER

Logrotate for Docker

  • Create Logrotate config file for Docker containers under /etc/logrotate.d/docker-container with the following content:
/var/lib/docker/containers/*/*.log {
  rotate 8
  • Test it with: logrotate -fv /etc/logrotate.d/docker-container

Docker after dist upgrade

  • Re-enable repo
    sudo add-apt-repository "deb [arch=amd64] <replace with lsb_release> stable"
  • update the package database with the Docker packages from the newly added repo:
    sudo apt-get update
  • Make sure you are install from the Docker repo instead of the default Ubuntu repo:
    apt-cache policy docker-ce
  • upgrade packes
    sudo apt-get install docker-ce docker-ce-cli
  • reboot


  • TBD


  • Update repos and upgrade system
    sudo apt-get update
    sudo apt-get upgrade
  • Install fail2ban with sudo apt-get install fail2ban
  • Create config file /etc/fail2ban/jail.local and add a jail for the SSH Deamon
enabled = true
port = <ssh port>
filter = sshd
logpath = /var/log/auth.log
maxretry = 3