Install and make GNU GCC 10 default in Ubuntu 20.04 Focal

The best way to install and use GNU GCC 10 is to install first, build-essential package, which will pull in the GNU GCC 9.2, and then install the GNU GCC 10. In fact, it is possible to install only GNU GCC 10 packages, but build-essential brings with it many additional packages, which are mandatory for the configuration and compiling stages.
GNU GCC is included in the official Ubuntu Focal repository! It just needs to be installed and made to be the default compiler.

Install build-essential ensures all generic packages to be installed, which are involved in the building process of a software product.

There are three steps to install and use GNU GCC 10 under Ubuntu 20.04:

  1. Install build-essential package.
  2. Install gcc-10 packages (g++, too).
  3. Make GNU GCC 10 default compiler – use update-alternatives to point the GNU GCC 10 as the default compiler

Four simple lines and the third is a little bit more complex:

apt update -y
apt upgrade -y
apt install -y build-essential
apt install -y gcc-10 g++-10 cpp-10
update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-10 100 --slave /usr/bin/g++ g++ /usr/bin/g++-10 --slave /usr/bin/gcov gcov /usr/bin/gcov-10

Always update and upgrade before installing new software. Use sudo before each command, if installation is performed by a user other than root:

sudo apt update -y
sudo apt upgrade -y
sudo apt install -y build-essential
sudo apt install -y gcc-10 g++-10 cpp-10
sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-10 100 --slave /usr/bin/g++ g++ /usr/bin/g++-10 --slave /usr/bin/gcov gcov /usr/bin/gcov-10

It is a good idea to install cmake package, in addition to the above, because cmake is not included in build-essential:

apt install -y cmake

The apt output of installing GNU GCC 10

Many additional packages like multiple perl modules, libraries and make are installed.
Keep on reading!

Chromium browser in Ubuntu 20.04 LTS without snap to use in docker container

Ubuntu team has its own vision for the snap ( service and that’s why they have moved the really big and difficult to maintain Chromium browser package in the snap package. Unfortunately, the snap has many issues with docker containers and in short, it is way difficult to run snap in a docker container. The user may just want not to mess with snap packages (despite this is the future according to the Ubuntu team) or like most developers they all need a browser for their tests executed in a container.
Whether you are a developer or an ordinary user this article is for you, who wants Chromium browser installed not from the snap service under Ubuntu 20.04 LTS!
There are multiple options, which could end up with a Chromium browser installed on the system, not from the snap service:

  1. Using Debian package and Debian repository. The problem here is that using simultaneously Ubuntu and Debian repository on one machine is not a good idea! Despite the hack, Debian packages are with low priority –
  2. Using Google Chrome It is just a single Debian package, which provides Chromium-like browser and all dependencies requesting the Chromium browser package are fulfilled.
  3. Using Chromium team dev or beta PPA ( for the nearest version if still missing Ubuntu packages for Focal (Ubuntu 20.04 LTS).
  4. more options available?

This article will show how to use Ubuntu 18 (Bionic) Chromium browser package from Chromium team beta PPA under Ubuntu 20.04 LTS (Focal). Bionic package from the very same repository of Ubuntu Chromium team may be used, too.

All dependencies will be downloaded from the Ubuntu 20.04 and just several Chromium-* packages will be downloaded from the Chromium team PPA Ubuntu 19 repository. The chances to break something are really small compared to the options 1 above, which uses the Debian packages and repositories. Hope, soon we are going to have focal (Ubuntu 20.04 LTS) packages in the Ubuntu Chromium team PPA!


An example of a Dockerfile installing Chromium (and python3 selenium for automating web browser interactions)

RUN apt-key adv --fetch-keys "" \
&& echo 'deb bionic main ' >> /etc/apt/sources.list.d/chromium-team-beta.list \
&& apt update
RUN export DEBIAN_FRONTEND=noninteractive \
&& apt-get -y install chromium-browser
RUN apt-get -y install python3-selenium

First command adds the repository key and the repository to the Ubuntu source lists. Note we are adding the “bionic main”, not “focal main”.
From the all dependencies of the Bionic chromium-browser only three packages are pulled from the Bionic repository and all other are from the Ubuntu 20 (Focal):

Get:1 bionic/main amd64 chromium-codecs-ffmpeg-extra amd64 84.0.4147.38-0ubuntu0.18.04.1 [1174 kB]
Get:5 bionic/main amd64 chromium-browser amd64 84.0.4147.38-0ubuntu0.18.04.1 [67.8 MB]
Get:187 bionic/main amd64 chromium-browser-l10n all 84.0.4147.38-0ubuntu0.18.04.1 [3429 kB]

Here is the whole Dockerfile sample file:

#   Docker file for the image "chromium brower without snap"
FROM ubuntu:20.04

#chromium browser
#original PPA repository, use if our local fails
RUN echo "tzdata tzdata/Areas select Etc" | debconf-set-selections && echo "tzdata tzdata/Zones/Etc select UTC" | debconf-set-selections
RUN export DEBIAN_FRONTEND=noninteractive && export DEBCONF_NONINTERACTIVE_SEEN=true
RUN apt-get -y update && apt-get -y upgrade
RUN apt-get -y install gnupg2 apt-utils wget
#RUN wget -O /root/ "" && apt-key add /root/
RUN apt-key adv --fetch-keys "" && echo 'deb bionic main ' >> /etc/apt/sources.list.d/chromium-team-beta.list && apt update
RUN export DEBIAN_FRONTEND=noninteractive && export DEBCONF_NONINTERACTIVE_SEEN=true && apt-get -y install chromium-browser
RUN apt-get -y install python3-selenium

Desktop install

The desktop installation is almost the same as the Dockerfile above. Just execute the following lines:
Keep on reading!

Software and technical overview of Ubuntu 20.04 LTS server edition

Ubuntu 20.04 LTS server edition offers the following software and versions:


  • linux kernel – 5.4.0 – 5.4.0-29-generic
  • System
    • linux-firmware – 1.187
    • libc – 2.31 – 2.31-0ubuntu9
    • GNU GCC – multiple versions available – 7.5.0, 8.4.0, 9.3.0 and 10-20200411. The exact versions – 7.5.0-6ubuntu2, 8.4.0-3ubuntu2, 9.3.0-10ubuntu2 and 10-20200411-0ubuntu1
    • OpenSSL – 1.1.1f – 1.1.1f-1ubuntu2
    • coreutils – 8.308.30-3ubuntu2
    • apt – 2.0.2ubuntu0.1
    • rsyslog – 8.2001.0 – 8.2001.0-1ubuntu1
  • Servers
    • Apache – 2.4.41 – 2.4.41-4ubuntu3
    • Nginx – 1.17.10 – 1.17.10-0ubuntu1
    • MySQL server –
    • MariaDB server – 10.3.22 – 10.3.22-1ubuntu1
    • PostgreSQL – 12.2-4
  • Programming
      LTS the user may install

    • PHP – 7.4 – 7.4.3-4ubuntu1.1
    • python – 3.8.2 (3.8.2-0ubuntu2) and also includes 2.7.17 (2.7.17-2ubuntu4)
    • perl – 5.30.0 and also includes perl 6 6.d-2
    • ruby – 2.7 – 2.7+1
    • OpenJDK – includes multiple versions – 8, 11, 13 and 14. The exact versions are 8u252-b09-1ubuntu1, 11.0.7+10-3ubuntu1, 13.0.3+3-1ubuntu2 and 14.0.1+7-1ubuntu1
    • Go lang – multiple versions – 1.13.8 and 1.14.2. The exact versions – 1.13.8-1ubuntu1 and 1.14.2-1ubuntu1
    • Rust – 1.41.0 – 1.41.0+dfsg1+llvm-0ubuntu2
    • Subversion – 1.13.0 – 1.13.0-3
    • Git – 2.25.1 – 2.25.1-1ubuntu3
    • llvm – multiple versions – 6, 7, 8, 9 and 10. The exact versions – 6.0.1-14, 7.0.1-12, 8.0.1-9, 9.0.1-12, 10.0-50~exp1
  • Graphical User Interface
    • Xorg X server – 1.20.8 – 1.20.8-2ubuntu2
    • GNOME (the GUI) – 3.36.x – Gnome Shell – 3.36.1

Note: Not all of the above software comes installed by default. The versions above are valid for the intial release so in fact, these are the minimal versions you get with Ubuntu 20 LTS and installing and updating it after the initial date may update some of the above packages with new versions. Installed packages are 582 occupying 11G space.

During the installation wizard you may want to install the following snap software environments. Of course, this software is available after the installation setup, too.

The test server is equipped with “Threadripper 1950X AMD“, which is 16 cores CPU.
Check out Minimal installation of Ubuntu server 20.04 LTS, too.

Keep on reading!

Minimal installation of Ubuntu server 20.04 LTS

This tutorial will show you the simple steps of installing a modern Linux Distribution – Ubuntu server 20.04 LTS edition. Following most of the default options during the setup configuration for simplicity.

Here are some basic data from the default installation setup settings:

  1. Installed packages – ~582 occupying 11G of space.
  2. 3 partitions when using automatic patition layout – boot efi, swap and root.
  3. ext4 used for the root parition.

We used the following ISO for the installation process – Ubuntu 20.04 LTS (Focal Fossa):

It is a LIVE image so you can try it before installing it. The easiest way is just to download the image and burn it to a DVD disk and then follow the installation below:

SCREENSHOT 1) Boot from the disk or USB – whatever you made after downloading the ISO file from Ubuntu official source.

On the image here the DVD is used to boot in UEFI mode installation.

main menu
boot uefi dvd

Keep on reading!

Mirror a PPA repositories using aptly – PHP (ppa:ondrej/php)

This is a simple example of how to mirror a PPA repository to a local server. The Ubuntu PPA to mirror is ppa:ondrej/php, which offers the user different PHP version generally not available in the Ubuntu installation. Of course, the user should be very careful about adding PPA repositories, because they are exactly what the abbreviation stands for Personal Package Archives.

If you want to know how to install and a brief description of what is aptly you may want to read our previous article – Install aptly under Ubuntu 18 LTS with Nginx serving the packages and the first steps

What we are going to do – this is what you need to have a mirror of an external application repository:

  1. Install aptly in Ubuntu 18 LTS
  2. Create a mirror in aptly
  3. Create a snapshot of the mirror created before
  4. Publish the snapshot to be used in other servers.

and at the last step there is an example how to use the mirror in your local machines.

STEP 1) Install aptly in Ubuntu 18.04 LTS.

As mentioned already you may follow our article on the subject – Install aptly under Ubuntu 18 LTS with Nginx serving the packages and the first steps. The following steps are based on this installation!
The aptly home directory is in “/srv/aptly”. We use the “aptly” user and change to it to manipulate the aptly installation.
Change the user to aptly, because under this user the mirror process will happen.

root@srv ~ # su - aptly

STEP 2) Create a mirror in aptly.

Prepare the keys (aptly needs to have the Ubuntu keys in its trustedkeys keyring):

aptly@srv:~$ gpg --no-default-keyring --keyring trustedkeys.gpg --keyserver --recv-keys 4F4EA0AAE5267A6C
gpg: requesting key E5267A6C from hkp server
gpg: key E5267A6C: public key "Launchpad PPA for Ond\xc5\x99ej Sur´┐Ż" imported
gpg: Total number processed: 1
gpg:               imported: 1  (RSA: 1)

Here we’ve used the method to obtain the key from a GPG KEY server, but the key can be downloaded directrly from the original repository as suggested in the error message below.
If you are not sure where to download the key you could always just try to create the mirror ( in fact, this is in STEP 3) ) and get the error for missing key and how to obtain the key:
Keep on reading!

Debug Ubuntu preseed failure – select and install software

Preparing the preseed for unattended installation sometimes could be challenging. This article presents the right way to analyze an installation failure in one of the main steps – “select and install software”.
There is a ubuntu installation preseed file for our Bionic unattended installation, which uses the “pkgsel” to install first packages in the new system:

d-i pkgsel/include string openssh-server wget vim git python gpg ntp
d-i pkgsel/upgrade select full-upgrade
d-i pkgsel/update-policy select unattended-upgrades

When an installation step in the preseed of a unattended installation fails the setup stops with a “Continue” confirmation.

main menu
“select and install software” – step failed

Here is what you can do to check what exactly fails in step “select and install software”:

  1. Start a shell in the current installation boot. Press “Ctrl+Alt+F2” to start the shell. You may use “Ctrl+Alt+F3” and “Ctrl+Alt+F4” for two more consoles and “Ctrl+Alt+F1” to return to the installation wizard.
  2. Check the /var/log/syslog, in which file the debconf writes the logging information.
  3. Find the lines where the step “select and install software” starts and look for errors after that. In this file, you can see all the step titles during, which the setup passes and they are named the same way the windows’ titles during the installation wizard.

Here is the real world output

Presing the “CTRL+ALT+F2” to start the BusyBox built-in shell, which is ash not bash!

Be careful there are some difference between ash and bash.

main menu
Installation wizard – BusyBox built-in shell (ash)

Last 20 lines shows the problem – pkgsel failed to install packages in step “select and install software”.

The installation wizard stops.

main menu
debconf logging using syslog – pkgsel

The problem is in the package “ntp”, the setup cannot install the “ntp” package because of unmet dependencies.

Because it is not so important to install ntp at this stage we added the package to the script executed in “preseed/late_command” and removed the package from the pkgsel line in the preseed file. In general, our problem was because we set local repositories for the bionic packages, but the setup cannot update list of available packages when the you set Bionic mirror to be unofficial local repository.

main menu
Package because of unmet dependencies

Install aptly under Ubuntu 18 LTS with nginx serving the packages and the first steps

This article is how to install aptly software, which offers easy Debian repository management.
First, few words for aptly and what tasks are really simple to do:

  • Mirror an existing (remote) repository. Make a local copy of Debian or Ubuntu repostories for all your internal infrastructure.
  • Create your own repositories
  • Create snapshots of repositories and mirrors.
  • Merge repositories
  • Make diff between repositories (in fact snapshots of repositories, but you may make a mirror of an repository and then make a snapshot and then make a diff with some other snapshot to see the changes between the different repositories or the time the snapshots are made).
  • Remove or add individual packages from official mirrored repositories.
  • Use api calls to manage the repositories. HTTP REST API is still in development, but a big part of it works.

For more information you may visit the official documentation page –

We are going to install the aptly and despite it could be used to serve the repository files we will use the Nginx web server for this work. Nginx is a more fast and reliable web server with easy installation of SSL certificates for our repositories.
The aptly is included in official Ubuntu repositories in the component universe, but at present, it is 2 to 3 versions behind the stable one from the aptly site, so we are going to use their repository to install aptly. Still, if you do not want to use
Keep on reading!

Install OpenStack swift client only

To manage files in the OpenStack cloud you need the swift client. This is not so tiny python tool (a lot of dependencies), which offers by means of files (as files are objects for the OpenStack):

  • delete – Delete files, directories and sub-directories. Be careful with a simple command you can delete all your files at once. “Delete a container or objects within a container.”
  • download – Download files to your local storage. “Download objects from containers.”
  • list – List all files in the main directory (i.e. the container), cannot be listed files in sub-directories. The output will be a file with path per line or you can enable extended output to show file size, time modified, the type of the file and the full file path. “Lists the containers for the account or the objects for a container.”
  • post – Creates containers and updates metadata, could create seurity keys for temporary urls – “Updates meta information for the account, container, or object; creates containers if not present.”
  • copy – Copy files to a new place within a container or to a different container. “Copies object, optionally adds meta”
  • stat – Display information for files, container and your account. No information is available per directory. Most typically you will read the file length, the type and modifcation date. “Displays information for the account, container, or object”
  • upload – uploads files and whole directories in a container – “Uploads files or directories to the given container.” You can read our article here – Upload files and directories with swift in OpenStack
  • capabilities – List the configuration options of your account like file size limits, file amount limits , limit requests per seconds and so on and which additional middleware your instance supports like bulk_delete, bulk_upload (the name are self-explainatory) – “List cluster capabilities.”
  • tempurl – Generate a temporary url for a file protected with time validity and a key – “Create a temporary URL.”
  • auth – Show your authentication token and storage url – “Display auth related environment variables.”

The text in the hyphens is from the swift help command. If you do not know what is a container with simple words these are the main sub-directories in your account if you use the list command without any argument (not adding a name after “list”):

myuser@myserver:~$ swift --os-username myusr --os-tenant-name myusr --os-password mypass --os-auth-url list

The best way is to install the swift client from the package system of your Linux Distribution. The package system ensures the programs you install and upgrade are consistent within dependencies upgrades.

When you install this package “python-swiftclient” it depends on multiple python packages, which might be upgraded later, too, but the package system of a Linux distribution ensure the programs of python-swiftclient will work with them

. On the contrary, if you install it manually even with “pip” as it is offered in OpenStack site it is unsure what will happen and even your client program from “python-swiftclient” could stop working because of an upgraded dependancy library. Of course, the packages from the official package system could be a little bit older (but probably more stable) than the manual installs from the OpenStack official site. Still if you would like to install it with “pip” here you can check how you can do it:
Keep on reading!

Ubuntu with PHP 7.2 and mcrypt module

As mentioned in our previous article PHP 7.2 or PHP 7.3 with mcrypt – manual build the PHP versions 7.2 and 7.3 do not include PHP mcrypt module. The mcrypt module was part of PHP 5 till 7.1, in which it was deprecated and removed in 7.2.
In this article we show how to build mcrypt module for Ubuntu based on our previous article showed above. Because of the great popularity of Ubuntu and it has no PHP mcrypt package in Ubuntu package system unlike other Linux distributions (like Gentoo, which created a package) we decided to make this article.

For our purpose we use Ubuntu 18.04.2 LTS and here is what the steps to have the mcrypt PHP module:

STEP 1) Update and install mcrypt library and header development packet

sudo apt update -y
sudo apt install -y libmcrypt-dev

STEP 2) Install the GNU GCC build utility and the PHP dev packet

This is the compiler to build the module.

sudo apt install -y build-essential
sudo apt install -y php7.2-dev

STEP 3) Download the PHP mcrypt module and build it.

mkdir mcrypt-php-module-manual
cd mcrypt-php-module-manual
tar xzf mcrypt-1.0.2.tgz
cd mcrypt-1.0.2
libtoolize --force
sudo make install

STEP 4) Load the module in the PHP configuration (we use PHP-FPM and PHP-CLI) and block future PHP versions to be installed when apt update is used.

Because we compile the PHP mcrypt module for the specific currently installed PHP we do not want to upgrade our PHP when there is an update and the mcrypt module to fail to load. Each change of the PHP version (upgrade) would require a recompile against the current PHP version. To see more for holding and unholding Ubuntu packages – apt-mark – upgrade with the exception of certain packages Of course, if there is an update for PHP you must install it just recompile the mcrypt package, too!

echo "" > 20-mcrypt.ini
sudo cp 20-mcrypt.ini /etc/php/7.2/cli/conf.d/20-mcrypt.ini
sudo cp 20-mcrypt.ini /etc/php/7.2/fpm/conf.d/20-mcrypt.ini
sudo apt-mark hold php-cli php7.2-cli php-fpm php7.2-fpm

Keep on reading!

Ubuntu apt – InRelease is not valid yet (invalid for another 151d 18h 5min 59s)

Invalid time could cause your server (or probably your virtual server or docker instance) to be unable to use Ubuntu’s packaging system apt. It is a typical thing if your virtual or docker instance does not use automatic time synchronization.

It is really important even small installation and virtualized environments to have automatic time synchronization or the service they provide could become error prone with time!

The “apt” just reports the repositories are not valid yet:

myuser@my-server-pc:~$ sudo su
root@my-server-pc:/home/myuser# apt update
Hit:1 bionic InRelease
Get:2 bionic-updates InRelease [88.7 kB]
Get:3 bionic-backports InRelease [74.6 kB]
Get:4 bionic-security InRelease [88.7 kB]
Reading package lists... Done                                 
E: Release file for is not valid yet (invalid for another 151d 18h 5min 59s). Updates for this repository will not be applied.
E: Release file for is not valid yet (invalid for another 151d 17h 16min 26s). Updates for this repository will not be applied.
E: Release file for is not valid yet (invalid for another 151d 17h 15min 3s). Updates for this repository will not be applied.
root@my-server-pc:/home/myuser# date
Thu Jan 17 15:11:56 UTC 2019

The clock shows 17 January 2019, but now is 18 June 2019! This is a Ubuntu virtual server with the minimal installation.

The solution is to synchronize your clock manually or use a service (the better way)!

Keep on reading!