Forem: Abdenour ALIANE

Install Linux 6.2 (and 6.3) on Google Cloud Compute Engine instance

Abdenour ALIANE — Mon, 20 Feb 2023 15:36:37 +0000

Update : Use the same trick to install Version 6.3 !
6.2 is here, here is what's new, but we will not focus on that, but how to try it on Google Cloud !

Be careful, this is an unsigned kernel, The system will fail to boot in a secure boot environment !

Before we start, I need you to do two important steps, so in case something goes wrong, you can always go back :

1- You need ton install the Ops Agent so you can see what happens inside your instance,
2- Create a backup or make a snapshot and create a disk from this snapshot.

Create a snapshot,

Covert it to disk to be attached to the instance

Now that you took care of the backup plan, let's dive in !

Here is what we do have with a default Ubuntu 18.04 installation (there is also 20.04 and 22.04 as LTS, but here, we want just to make a small demo) :

We need to add mainline package to our repos list so we can install it using apt

sudo add-apt-repository ppa:cappelikan/ppa

Then update the new repos by

sudo apt update

then we just install it using

sudo apt install -y mainline

To get all available kernels, we just make

mainline --list

Then, we choose what to install, by explicitly giving the version,

sudo mainline --install 6.2.0

or, if we want to get the latest stable kernel, we simply :

sudo mainline --install-latest

Restart, and voilà !

...

But here is an issue, how do we go back to old kernel ?

The problem here, is we are accessing using SSH, and kernel selection is done from Grub Menu, and SSH is not available at this stage, which means we need another way, here is how !

Here is what we have now as installed kernels, we can use one of this commands :

dpkg --list | grep -i linux-image

apt list --installed | grep -i linux-image

Now, let's change something in default grub loading, here is the trick, but before, we need to understand how Grub works :

Grub menu on a machine that we have physical access can be tuned to show a menu at restart, so we generally have two options (menu) : the default kernel, and advanced mode that have a submenu, and they are assigned by indexes starting with 0 :
1- first menu entry = 0
2- second menu entry = 1
and so on ...
and each menu has a submenu with index numbers, but to not complicate this, we will flatten this submenus to make it easier
Grub saves its file to /boot/grub/grub.cfg , but this file should never be modified manually, as it's a result of some scripts (that we will know shortly), so eachtime for example we do a kernel update, it will be erased a new one will be generated, so we need to modify this script that generates the file, and not the file itself :

The files that we need to modify for our case is /etc/default/grub

And as you can see, the first option is 0 which means take the first entry in the menu and validate it, we will change that, but first we need to :

flatten the menu to avoid submenus
get the index of the kernel version we need

Here is how it was with default values (with submenus):

Let's first add this entry to disable submenus :

GRUB_DISABLE_SUBMENU=y

Then let's validate the config by running the script to re-generate the /boot/grub/grub.cfg by running :

sudo update-grub

And it's flat now, no more submenus !

Now we need to understand the origin of other variables from other files, so when we do update-grub there is also a bunch of scripts that runs from /etc/grub.d/

On Google Cloud, there is another file, which is :

/etc/default/grub.d/50-cloudimg-settings.cfg

So let's change this value, it will override the global one ...

But to replace it with what ?

Well, let's enumerate the menus we got starting with zero

So now that we know that we need entry 2 let's replace it :

Restart, and voilà again !

Learn Kubernetes on your laptop with Minikube

Abdenour ALIANE — Mon, 28 Nov 2022 16:59:35 +0000

First, let's be clear; future is containers !

This is a long debate, but as we asked in the past "Does it work on Windows or Linux", we will just ask "Does it work on Kubernetes" !

Cloud is here, Multi Cloud is here, Hybrid Cloud is here, and to make everything works in a "perfect" way, there is Kubernetes, there are tons of tutorials, on Youtube, on Google ,

Kubernetes is what orchestrates containers on clusters, it uses config files (yaml) where everything is perfect and tries to mimic this perfect world (state).

The architecture of Kubernetes needs some time to be understood, but to make stuff run (make hands dirty, then learn what made them dirty !), we can use Minikube, and of course there are alternatives, and tutorials too for each of them !

But this article will try to make two hits with one shot; use Minikube while you already have installed gcloud SDK

The installation will be made in a headless server Ubuntu 22.04 fresh minimal installation, Ubuntu uses Debian family commands, you can replace them with simple transitions if you are on Redhat family (yum/dnf instead of apt)

You can follow the instruction directly from the link, or, use the ones here :

First, let's download the SDK :

curl -O https://dl.google.com/dl/cloudsdk/channels/rapid/downloads/google-cloud-cli-410.0.0-linux-x86_64.tar.gz

Then let's uncompress it

tar -xf google-cloud-cli-410.0.0-linux-x86_64.tar.gz

Then let's run the script :

./google-cloud-sdk/install.sh

And just follow the instructions by answering with one letter :

As you can see, we need to re-run .bashrc file to enable the new inserted path, it will insert those two lines :

# The next line updates PATH for the Google Cloud SDK.
if [ -f '/home/yourUserName/google-cloud-sdk/path.bash.inc' ]; then . '/home/yourUserName/google-cloud-sdk/path.bash.inc'; fi

# The next line enables shell command completion for gcloud.
if [ -f '/home/yourUserName/google-cloud-sdk/completion.bash.inc' ]; then . '/home/yourUserName/google-cloud-sdk/completion.bash.inc'; fi

Then, each time we need to install a component we just need to run

gcloud components install SomeThing

That we already got its name from

gcloud components list

So, let's install minikube ^_^

To make minikube (our mini kubernetes) run, we just run minikube start

But here is the catch; we need some hypervisor (Virtualbox, VMWare, KVM) or a container engine (Docker, Podman) to make it run, so we will install KVM as it's already available on Linux (think about Hyper-V on Windows)

The easiest way is to install Docker, but as we want to make something outside of Docker and make you discover 'new' stuff, let's make it differently

sudo apt update

sudo apt install qemu-kvm libvirt-daemon-system libvirt-clients

As you can see, we need to do some security commands, as we don't want to run sudo here, so the trick is to add the user to the two groups, kvm and libvirt

We need to restart to make it work.

And voilà !

*Hint : this is just a normal kvm virtual machine, this is the interface of Cockpit, the virt-manager alternative *

But as you see, the main kubectl command that we find in every tutorial is missing, to solve this, we just need to run :

minikube kubectl

And it will download it

Now, why we can't by default run kubectl, this is to not make conflict between the kubectl you install from the main Kubernetes installation, and minikube installation.

You can create an alias for this (you need to put the alias inside .bashrc to make it work eachtime you close the console):

But you can still install kubectl using gcloud components install kubectl as this will allow you to use GKE too, and it works with minikube

Here is a simple difference between both :

Oh, you want to know what is GKE ?

Now you can start practicing and creating what will be the future !

Update env variables in Windows 10 without Restarting/Logout

Abdenour ALIANE — Mon, 06 Jun 2022 12:38:37 +0000

Hi,
a quick post, I just installed WAMP and I needed to work with MySQL from the shell (Powershell or cmd or whatever :P ), I added the bin folder to the Environment Variables but without restarting, here is how to do it quickly :

1 - Install Chocolatey as an Admin using this command from PowerShell :
Set-ExecutionPolicy Bypass -Scope Process -Force; [System.Net.ServicePointManager]::SecurityProtocol = [System.Net.ServicePointManager]::SecurityProtocol -bor 3072; iex ((New-Object System.Net.WebClient).DownloadString('https://community.chocolatey.org/install.ps1'))

2 - Run this simple command : RefreshEnv.cmd (you can use Refre and type Tab like you do in Linux...right ? ^^ )

3 - Done

Use VMware Workstation with the latest Linux Kernel

Abdenour ALIANE — Fri, 06 May 2022 23:51:27 +0000

Azul,
This is my first article, this my Hello World in dev.to community, I am here to help people as I got and still get helped from those online articles, but, to encourage people from my community to write and share their knowledge !

I am Abdenour ALIANE, Aicignaw Consulting founder, and teacher (and of course a student), I will write about computer (sure, since I am here), focusing on Cloud Computing (Google Cloud and on-premise solutions) and Linux, and everything related to those two big topics, and I will always try to break the topic to something anyone could understand (I suppose that I am a newbie that comes and read this article because I searched for a keyword on Google, and of course we never stop learning, so I am still a newbie, that's the key to learn ! so sorry if my articles will seem basic, and if you dont understand, please let me know in the comments section)

Today, I will start with this simple way on how to use VMWare Workstation on Linux distribution with a new kernel (since hypervisors and virtualization is important to explain how cloud works), if you know the basics, just scroll down to the yawning cat picture ^_^

Well, first, let's break down what I said :

Linux is a Kernel, a kernel is that part who manages the electricity flaw (those 1 and 0 signals), so if we try to understand using what most of people use on Desktop: Microsoft Windows :

When we install a driver, we are installing some 'code' that will work with our hardware to tell them how to behave; so when we find a driver compatible with Windows 8.1, that means, it works with the Windows kernel of this version, so chances that it could work with Windows 10, but Windows XP drivers could break for Windows 10 even if it's the same architecture as the two kernels have lot of differences
When Windows starts, the kernel is the part that protects the hardware from being broken by something a user or a program could do, which means, a virus for example (which is a program but does something a user will not like ...) will not burn the hardware by sending too much electricity to it (we will see that concept a lot with virtualization in next articles),

Linux is named after the guy who made it, Linus Torvalds, you can even check his git repo, or download it from the official website, but you need then to compile it to your own distribution, you can Google for it, I will make a topic on this later.
So now that we understood what is a kernel, what we use are Distributions and there are a LOT !

The good part of using a Linux distribution, is its modularity; we can install Ubuntu for example, change its user interface, and update its kernel to try some new features and bring some new hardware compatibility, without even touching the distribution version !

Important notice :
In computer world, there are two kind of people :

Users who like to test and try new stuff, if it breaks, even if there is a loss, but there is time to repair,
Professionals using machines as servers, no time to lose :

Here, the most important is stability over new stuff, they only do security patches and important updates, that's why some distributions offer what is called an Long Term Support (LTS)
Those servers are headeless, that's why we avoid installing graphical interface on those Linux distributions, so, headeless keyword is also used in Linux to say they dont have GUI
* Headeless Linux means less security holes
That is said, DONT TRY THIS AT ... SERVER

So, since you decided to change the kernel to the latest stable version, here is what happens, and how to solve the problem :

For this, I will give you my own experience :

I use Pop!_OS 22.04 LTS, which is based on Ubuntu 22.04 LTS which is a Debian based distribution, I used this version because this is what I personally found good on my laptop with Nvidia Optimus

if you are an Arch user, and want something on top of KDE that supports Optimus, there is the amazing EndeavourOS but that's not our main topic, this is just for people who want to discover the Linux world

Let's begin :

This is how to get your Linux distribution version :
cat /etc/os-release
And this is how to get your kernel version :
uname -r

The result

When you run VMWare Workstation, it will ask you to compile some modules for this kernel

Then it will start building the modules vmmon and vmnet

And this where it messes and I got the error (unable to install all modules):

The log shows compilation error due to C libraries missing ...

So here is the solution that worked with me :

The solution is in this excellent repo, it is described :

This repository tracks patches needed to build VMware (Player and
Workstation) host modules against recent kernels. As it focuses on recent
kernels (older ones do not need patching), only vmmon and vmnet modules are
currently handled as the rest has been upstreamed for some time.

First, let's clone it to our machine
git clone https://github.com/mkubecek/vmware-host-modules.git

Git will create a new folder and name it the same name as the git repo, which is vmware-host-modules

cd vmware-host-modules

The repo appears almost empty, the files we need are in the branchs, we can check them with

git branch -r

We will find that it contains branchs for Player and Workstation, with their respective versions, I am using 16.2.4, to get the branch name, we can directly use :

If you use the latest Worsktation at the time of writing/editing this article, which is workstation-17.0.0 just replace the version number and you are all set !

git branch -r | grep -i 16.2.4

Then we switch to that branch depending on which version you need :

git checkout workstation-16.2.4

You can avoid all this by directly clone the branch (replace the VMWare version with the one you use) :
git clone -b workstation-16.2.4 https://github.com/mkubecek/vmware-host-modules.git

and then once we are there, we just need to compile our modules and install them with the famous :

make && sudo make install

it should not take time, and TADA !

Update : Nov 2022

After upgrading to kernel version 6.xx I got an issue, here is simply how to solve it :

... after doing make

tar -cf vmnet.tar vmnet-only

tar -cf vmmon.tar vmmon-only

sudo mv vmnet.tar /usr/lib/vmware/modules/source/

sudo mv vmmon.tar /usr/lib/vmware/modules/source/

sudo vmware-modconfig --console --install-all

And if you get issues with gcc as incompatible with the one you are using (gcc 11 vs gcc 12) just change the symlink to the newest one :

gcc --version

which gcc

Then :

sudo unlink /usr/bin/gcc

sudo ln /usr/bin/gcc-12 /usr/bin/gcc

And check again with

gcc --version