ubuntu


Rough notes on setting up an Ubuntu server with docker

Static IP

First, we set up a static IP to our Ubuntu server using netplan. To do so, we created the following file:

/etc/netplan/01-netcfg.yaml

using the following command

sudo nano /etc/netplan/01-netcfg.yaml;

and added the following content to it:

# This file describes the network interfaces available on your system
# For more information, see netplan(5).
network:
  version: 2
  renderer: networkd
  ethernets:
    enp3s0f0:
      dhcp4: no
      addresses: [192.168.45.13/24]
      gateway4: 192.168.45.1
      nameservers:
          addresses: [1.1.1.1,8.8.8.8]

To apply the changes, we executed the following:

sudo netplan apply;

Update everything (the operating system and all packages)

Usually, it is a good idea to update your system before making significant changes to it:

sudo apt update -y; sudo apt upgrade -y; sudo apt autoremove -y;

Install docker

In this setup we did not use the docker version that is available on the Ubuntu repositories, we went for the official ones from docker.com. To install it, we used the following commands:

sudo apt-get install ca-certificates curl gnupg lsb-release;
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo gpg --dearmor -o /usr/share/keyrings/docker-archive-keyring.gpg;
echo   "deb [arch=$(dpkg --print-architecture) signed-by=/usr/share/keyrings/docker-archive-keyring.gpg] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable" | sudo tee /etc/apt/sources.list.d/docker.list > /dev/null;
sudo apt-get update;
sudo apt-get install docker-ce docker-ce-cli containerd.io;

Install docker-compose

Again, we installed the official docker-compose from github.com instead of the one available in the Ubuntu repositories. At the time that this post was created, version 1.29.2 was the recommended one:

sudo curl -L "https://github.com/docker/compose/releases/download/1.29.2/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose;
sudo chmod +x /usr/local/bin/docker-compose;

Increase network pool for docker daemon

To handle the following problem:

ERROR: could not find an available, non-overlapping IPv4 address pool among the defaults to assign to the network

We created the following file,

/etc/docker/daemon.json

using the command:

sudo nano /etc/docker/daemon.json;

and added the following content to it:

{
  "default-address-pools": [
    {
      "base": "172.80.0.0/16",
      "size": 24
    },
    {
      "base": "172.90.0.0/16",
      "size": 24
    }
  ]
}

We executed the following command to restart the docker daemon and get the network changes applied:

sudo systemctl restart docker;

Gave access to our user to manage docker

We added our user to the docker group so that we could manage the docker daemon without sudo rights.

sudo usermod -aG docker $USER;

Deploying

After we copied everything in place, we executed the following command to create our containers and start them with the appropriate networks and volumes:

export COMPOSE_HTTP_TIMEOUT=120;
docker-compose up -d --remove-orphans;

We had to increase the timeout as we were getting the following error:

ERROR: for container_a  UnixHTTPConnectionPool(host='localhost', port=None): Read timed out. (read timeout=60)
ERROR: An HTTP request took too long to complete. Retry with --verbose to obtain debug information.
If you encounter this issue regularly because of slow network conditions, consider setting COMPOSE_HTTP_TIMEOUT to a higher value (current value: 60).

Stopping all containers using a filter on the name

docker container stop $(docker container ls -q --filter name=_web);

The above command will find all containers whose names contain _web and stop them. That command is actually two commands where one is nested inside the other.

#This command finds all containers that their name contains _web, using the -q parameter, we only get back the container ID and not all information about them.
docker container ls -q --filter name=_web;
#The second command takes as input the output of the nested command and stops all containers that are returned.
docker container stop $(docker container ls -q --filter name=_web);

Docker: WARNING: Host is already in use by another container

We use docker to manage multiple instances of various tools on a server that we control. We have an Nginx server working as a reverse proxy that forwards all requests to the appropriate containers in the configuration. Sometimes, after updating the container images and recreating the containers, we get the error that ports 80 and 443 are already in use by another container. This problem can happen even if no other container asks for them.

The following excerpt demonstrates the problem as mentioned above.

tux@server:~/docker-compose$ docker-compose up -d --remove-orphans;
Recreating container_a ... 
Recreating container_a ... done
Recreating container_b   ... done
Recreating container_c          ... 
Recreating nginx_reverse_proxy        ... error
Recreating container_d          ... done
Recreating container_e       ... done
Recreating container_f  ... done
WARNING: Host is already in use by another container

ERROR: for nginx_reverse_proxy  Cannot start service nginx_reverse_proxy: driver failed programming external connectivity on endpoint nginx_reverse_proxy (5a790ed7e1b24aa36cb88cbd3f49d306efa8fe023bf5b3312655218319f23a35): Bind for 0.0.0.0:443 failed: port is already allocated

ERROR: for nginx_reverse_proxy  Cannot start service nginx_reverse_proxy: driver failed programming external connectivity on endpoint nginx_reverse_proxy (5a790ed7e1b24aa36cb88cbd3f49d306efa8fe023bf5b3312655218319f23a35): Bind for 0.0.0.0:443 failed: port is already allocated
ERROR: Encountered errors while bringing up the project.
tux@server:~/docker-compose$ sudo systemctl restart docker.socket docker.service;

To solve this issue, we had to restart two services using the systemctl command:

  • docker.socket
  • docker.service

Specifically, on an Ubuntu server, we used the following command:

sudo systemctl restart docker.socket docker.service;

Compiling ffmpeg with NVIDIA GPU Hardware Acceleration on Ubuntu 20.04LTS

Please note that the following commands were executed on a system that already had CUDA support so we might be missing a step or two to enable NVIDIA CUDA support.

Install necessary packages

sudo apt-get install build-essential yasm cmake libtool libc6 libc6-dev unzip wget libnuma1 libnuma-dev nvidia-cuda-toolkit;

Clone and install ffnvcodec

git clone https://git.videolan.org/git/ffmpeg/nv-codec-headers.git;
cd nv-codec-headers;
sudo make install;
cd -;

Clone and compile FFmpeg’s public GIT repository with NVIDIA GPU hardware acceleration

git clone https://git.ffmpeg.org/ffmpeg.git ffmpeg/;
cd ffmpeg;
./configure --enable-nonfree --enable-cuda-nvcc --enable-libnpp --extra-cflags=-I/usr/local/cuda/include --extra-ldflags=-L/usr/local/cuda/lib64 --disable-static --enable-shared;
make -j 8;
sudo make install;

SUCCESS!

After performing the above steps, we were able to process media using ffmpeg without stressing our CPU! The workload was transferred to the GPU!


Symfony 5 skeleton project on Ubuntu

This guide will present the steps we followed on a GNU/Linux Ubuntu 20.04LTS to create a new project out of the Symfony 5 website skeleton.

Install core dependecies

First of all, we need to install all dependencies that we will need for sure.

sudo apt install curl gzip git php-cli php-xml php-mbstring php-intl php-mysql p7zip-full;

We chose to install the php-cli package instead of the php as we do not need to install all the additional dependencies php has, like apache2. Since we are working on a development computer, we can skip the required packages for deployment.

We decided to use MySQL in our project, so we installed the php-mysql package that provides the PDO for that database technology.

php-intl and php-mbstring were installed to suppress the following warnings:

Optional recommendations to improve your setup
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

 * mb_strlen() should be available
   > Install and enable the mbstring extension.

 * intl extension should be available
   > Install and enable the intl extension (used for validators).

Downloading and installing symfony

Since Symfony version 5, there is a new support application for the development of Symfony projects. Using the following commands:

  • we downloaded it from the official website,
  • installed it to our home folder,
  • and then moved it to /user/local/bin/symfony to be accessible from any terminal without changing the path each time.
wget https://get.symfony.com/cli/installer -O - | bash;
sudo mv ~/.symfony/bin/symfony /usr/local/bin/symfony;

In case you do not want to move the binary to /usr/local/bin you can either use it as a local file:

~/.symfony/bin/symfony;

or add it to your $PATH variable:

export PATH="$HOME/.symfony/bin:$PATH";

Creating a new project and making sure dependencies are met

After the above steps are done, we can clone the Symfony 5 skeleton and then use the symfony support application to check that our system has all the needed features.

symfony new symfony_project;
cd symfony_project;
symfony check:req;

If everything is OK, you should get a message similar to the one below:

$ symfony check:req

Symfony Requirements Checker
~~~~~~~~~~~~~~~~~~~~~~~~~~~~

> PHP is using the following php.ini file:
/etc/php/7.4/cli/php.ini

> Checking Symfony requirements:

...................................

                                              
 [OK]                                         
 Your system is ready to run Symfony projects 
                                              

Note  The command console can use a different php.ini file
~~~~  than the one used by your web server.
      Please check that both the console and the web server
      are using the same PHP version and configuration.

Starting a minimal web server to see the skeleton application

Using PHP’s built-in server, we can execute the skeleton application and see the result in our browser:

php -S 127.0.0.1:8000 -t public/;

Starting the Symfony minimal web server to see the skeleton application

Another option to check out your application is using the Symfony built-in web server, which is richer in features than the PHP server but lighter than Apache or Nginx. Below we present how to start it as an application in a terminal and how to start it as a detached service (leaving your terminal free for other operations).

#If you start it as it as an application, you will need to press Ctrl + C to kill it.
symfony serve;

Starting Symfony server as a detached service:

symfony serve -d;
#To stop it, use the following
symfony server:stop;
#Please note that the command contains the word server and not serve like before.

Adding more features to our project

To make our project more dynamic and versatile, we need to install a few packages using composer. Composer is a PHP utility for managing dependencies. It allows you to indicate the libraries your project relies on, and it will take care of installing and updating them. To fast install it, open a terminal and type the following command:

curl -Ss getcomposer.org/installer | php;
# Moving the composer into the /usr/local/bin/ folder will allow us to access it from any folder later on as that folder is in the default PATH variable. You could again avoid this step but it makes the process more user friendly.
sudo mv composer.phar /usr/local/bin/composer;

Allowing code annotations in our PHP code

After the composer is successfully installed, we can install the annotations package, which among other features, will allow us to define routes inside our PHP controller files.

composer require annotations;

A code example of that is the following:

<?php


namespace App\Controller;

use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\Routing\Annotation\Route;

class QuestionController extends AbstractController
{
    /**
     * @Route("/", name="app_homepage")
     */
    public function homepage()
    {
        return new Response('Done');
    }

    /**
     * @Route("/questions/{slug}", name="app_question_show")
     */
    public function show($slug)
    {
        $answers = [
            'a',
            'b',
            'c'
        ];
        dump($this);

        return $this->render('question/show.html.twig', [
            'question' => ucwords(str_replace('-', ' ', $slug)),
            'answers' => $answers
        ]);
        #return new Response(sprintf("The question: %s", $slug));
    }
}

Installing the twig package that allows us to work better with HTML templates

To avoid embedding HTML code in our PHP code, we can install twig, which provides a framework of templates to build several sites quickly.

composer require template;

Enriching the development experience

To debug in a better way our applications, we install the following two groups of packages that provide several debugging features, including a logging mechanism.

composer require profiler --dev;
composer require debug;

Avoid hardcoding assets in the HTML DOM

To avoid hardcoding items in your DOM (and forcing yourself to remember to edit them depending on the deployment options you are using), you can use the asset package that will handle most of those issues.

composer require symfony/asset;

Serializing more items and objects to JSON and XML

To enrich the power of API calls that return JSON or XML objects (like the code below)

return $this->json(/*...*/);

we can install the following serializer:

composer require symfony/serializer;

and be used as follows:

$serializer->serialize(
  $myObject,
  'json'
);

Develop using HTTPS / SSL for free

Although we are not super happy about installing local Certificate Authorities on our machines, we used the following commands to install the Symfony Certifying Authority certificate and enable HTTPS/SSL development without accepting a non-verified certificate in the browser each time.

sudo apt install libnss3-tools;
symfony server:ca:install;

If you do not install libnss3-tools, you will get the following warning:

$ symfony server:ca:install
You might have to enter your root password to install the local Certificate Authority certificate
Sudo password:
The local CA is now installed in the system trust store!
WARNING "certutil" is not available, so the CA can't be automatically installed in Firefox and/or Chrome/Chromium!
Install "certutil" with "apt install libnss3-tools" and re-run the command
                                                                                                        
 [OK] The local Certificate Authority is installed and trusted                                          
                                                                      

After you install it, the message will change as follows:

$ symfony server:ca:install
The local CA is now installed in the Firefox and/or Chrome/Chromium trust store (requires browser restart)!
                                                                                                        
 [OK] The local Certificate Authority is installed and trusted

Install Webpack Encore for the assets

To install Webpack encore, we need yarn. To get yarn, we need npm. So we need the following installation steps:

sudo apt install npm;
sudo npm install --global yarn;

After these steps are successful, in the project folder, execute the following commands to allow the yarn to perform all necessary installations and then use encore to monitor the assets and rebuild its cache. The settings are depended on the file webpack.config.js.

yarn install;
yarn encore dev --watch;

Below, we present an example file of webpack.config.js.

var Encore = require('@symfony/webpack-encore');

// Manually configure the runtime environment if not already configured yet by the "encore" command.
// It's useful when you use tools that rely on webpack.config.js file.
if (!Encore.isRuntimeEnvironmentConfigured()) {
    Encore.configureRuntimeEnvironment(process.env.NODE_ENV || 'dev');
}

Encore
    // directory where compiled assets will be stored
    .setOutputPath('public/build/')
    // public path used by the web server to access the output path
    .setPublicPath('/build')
    // only needed for CDN's or sub-directory deploy
    //.setManifestKeyPrefix('build/')

    /*
     * ENTRY CONFIG
     *
     * Add 1 entry for each "page" of your app
     * (including one that's included on every page - e.g. "app")
     *
     * Each entry will result in one JavaScript file (e.g. app.js)
     * and one CSS file (e.g. app.css) if your JavaScript imports CSS.
     */
    .addEntry('app', './assets/js/app.js')
    //.addEntry('page1', './assets/js/page1.js')
    //.addEntry('page2', './assets/js/page2.js')

    // When enabled, Webpack "splits" your files into smaller pieces for greater optimization.
    .splitEntryChunks()

    // will require an extra script tag for runtime.js
    // but, you probably want this, unless you're building a single-page app
    .enableSingleRuntimeChunk()

    /*
     * FEATURE CONFIG
     *
     * Enable & configure other features below. For a full
     * list of features, see:
     * https://symfony.com/doc/current/frontend.html#adding-more-features
     */
    .cleanupOutputBeforeBuild()
    .enableBuildNotifications()
    .enableSourceMaps(!Encore.isProduction())
    // enables hashed filenames (e.g. app.abc123.css)
    .enableVersioning(Encore.isProduction())

    // enables @babel/preset-env polyfills
    .configureBabelPresetEnv((config) => {
        config.useBuiltIns = 'usage';
        config.corejs = 3;
    })

    // enables Sass/SCSS support
    //.enableSassLoader()

    // uncomment if you use TypeScript
    //.enableTypeScriptLoader()

    // uncomment to get integrity="..." attributes on your script & link tags
    // requires WebpackEncoreBundle 1.4 or higher
    //.enableIntegrityHashes(Encore.isProduction())

    // uncomment if you're having problems with a jQuery plugin
    //.autoProvidejQuery()

    // uncomment if you use API Platform Admin (composer req api-admin)
    //.enableReactPreset()
    //.addEntry('admin', './assets/js/admin.js')
;

module.exports = Encore.getWebpackConfig();

Some settings for PHPStorm by JetBrains

Since the IDE we are using for PHP development is PHPStorm, we installed the recommended plugins for Symfony to it. In the following image, we list the three plugins that we installed.

Specifically, we installed:

  • Symfony Support
  • PHP Annotations
  • PHP Toolbox

After installing the three plugins, we navigated to the Symfony Plugin settings (which you can find either using the search functionality or under the menu: Languages & Frameworks > PHP > Symfony).

From there, we clicked on the Enable Plugin for this Project and then changed the Web Directory from web to public.