Lägg till:

spec:
containers:
- args:
- --secure-port=4443
- --cert-dir=/tmp
command:
- /metrics-server
- --kubelet-insecure-tls
- --kubelet-preferred-address-types=InternalIP,ExternalIP,Hostname
- --kubelet-use-node-status-port
- --metric-resolution=15s
image: k8s.gcr.io/metrics-server/metrics-server:v0.6.1
imagePullPolicy: IfNotPresent

1. Denna guide har en utmärkt beskrivning på hur en Elasticsearch, Fluentd och Kibana installeras på Kubernetes kluster. https://kamrul.dev/deploy-efk-stack-with-helm-3-in-kubernetes/

1. Spinn upp tre Linux servrar t.ex. som Virtual Machines på VirtualBox. Kör på Ubuntu 18.04.6 LTS (Bionic Beaver). Om möjligt kör på 4 vCPU, 8 GiB RAM, 30 GiB HDD på varje VM.
2. Uppdatera Ubuntu servrarna: sudo apt update –y && sudo apt upgrade –y
3. Installera vim och curl: sudo apt install vim curl –y
4. Installera docker:

    sudo apt install docker.io -y
    sudo systemctl enable docker.service
    sudo usermod -aG docker $USER
   

5. Fixa cgroups problem >1.22

   sudo cat << EOF | sudo tee /etc/docker/daemon.json
   {
   "exec-opts": ["native.cgroupdriver=systemd"],
   "log-driver": "json-file",
   "log-opts": {
   "max-size": "100m"
   },
   "storage-driver": "overlay2"
   }
   EOF
   

6. Lägg till repot för Kubernetes:

   echo 'deb [signed-by=/usr/share/keyrings/kubernetes-archive-keyring.gpg] https://apt.kubernetes.io/ kubernetes-xenial main' | sudo tee -a /etc/apt/sources.list.d/kubernetes.list

7. Ladda ned Google Cloud publika nyckel:

   sudo curl -fsSLo /usr/share/keyrings/kubernetes-archive-keyring.gpg https://packages.cloud.google.com/apt/doc/apt-key.gpg

8. Installera kubernetes:

   sudo apt update –y
   sudo apt installkubeadm=1.21.1-00 kubelet=1.21.1-00 kubectl=1.21.1-00 –y
   sudo apt-mark hold kubelet kubeadm kubectl
   

9. Inaktivera swap temporärt:

   sudo swapoff –a

10. Lägg till ip och hostname i filen /etc/hosts

<ip-till-nod> <hostname> t.ex. 10.128.0.3 k8scp

1. Skapa en kubeadm-config.yaml fil och lägg till följande i filen:

   apiVersion: kubeadm.k8s.io/v1beta2
   kind: ClusterConfiguration
   kubernetesVersion: 1.21.1   #<-- Use the word stable for newest version
   controlPlaneEndpoint: "k8scp:6443"   #<-- Use the node alias not the IP
   networking:
     podSubnet: 192.168.0.0/16   #<-- Match the IP range from the Calico config file 

Delete all files:

find /var/log -type f -delete

Delete all .gz and rotated file

find /var/log -type f -regex ".*\.gz$" find /var/log -type f -regex ".*\.[0-9]$"

Try run command without “-delete”, to test it.

By default there is no authentication in MongoDB. It means that it comes with empty authentication. So we should create users and roles manually. There are lots of ways to create MongoDB docker-compose with authentication. The most popular one of them is to write a bash script with user and roles then use it in docker-compose and another way is to create an init-mongodb.js file with users and roles and use it in docker-compose. But in this post, I will show you how you could create MongoDB docker-compose and then add users and roles manually. Lets start…

Run MongoDB docker-compose without authentication First of all we should run MongoDB docker-compose without auth. Using docker-compose up -d we could run it.

Connect MongoDB without auth inside container For doing that firstly we should run docker exec -it mongodb bash and enter inside the container. Then simply run mongo command to connect to mongodb.

Create user and roles for our MongoDB Firstly we will create admin user with username root and password root in admin database.

Then we need to create other user. Here I will create a demo user within demo database for our MongoDB:

Now we are ready to run MongoDB with auth.

Enable MongoDB auth in docker-compose In order to enable auth in MongoDB we will use --auth flag in docker-compose. After that we could use docker-compose up -d command again, to run MongoDB container.

Connect MongoDB with defined authentication In this step we can connect our db with defined authentication. Firstly again we need to run docker exec -it mongodb bash command in order to enter inside the container. Now we are in so we can connect our db. Here I write 2 command one of them is to connect admin db and another one is to connect demo db.

mongo -u root -p root --authenticationDatabase admin

mongo -u demo -p demo12345 --authenticationDatabase demo

Run the following commands:

docker run --rm --privileged multiarch/qemu-user-static --reset -p yes
docker buildx rm builder
docker buildx create --name builder --driver docker-container --use
docker buildx inspect --bootstrap

Inspect the builder by using the command:

docker buildx ls

Remove builder: docker buildx rm builder

Download git-sync repo git clone https://github.com/kubernetes/git-sync.git

Make sure you have buildx installed. If not, use the following steps:

export DOCKER_BUILDKIT=1
docker build --platform=local -o . git://github.com/docker/buildx
mkdir -p ~/.docker/cli-plugins
mv buildx ~/.docker/cli-plugins/docker-buildx

Make sure you have a multiarch bulder. Follow the guide 2020-11-11-Create-multiarch-docker-buildx-builder.

Go to the git-sync folder. Type the following to start the build process. make container REGISTRY=registry VERSION=tag GOOS=linux GOARCH=arm

Connect to your router via ssh, delete your /jffs/.le folder and execute service restart_letsencrypt command. Allow a minute for the task to complete.

Looks like the same problem described in this thread: Lets Encrypt not updating, or? (https://www.snbforums.com/threads/lets-encrypt-not-updating-or.59524/)

Reference: https://www.thegeekdiary.com/centos-rhel-7-how-to-make-custom-script-to-run-automatically-during-boot/

In RHEL 5 and 6, we were using automatic startup feature of RHEL through /etc/rc.d/init.d to run any script at system boot. Starting with RHEL 7 init is replaced by systemd and the prior method is now deprecated. There is another way in RHEL 7 to do the same.

Creating the custom script

1. Let us first create a sample custom script to be run at system boot automatically.

   vi /var/tmp/test_script.sh

    #!/bin/bash
    echo "This is a sample script to test auto run during boot" > /var/tmp/script.out
    echo "The time the script run was -->  `date`" >> /var/tmp/script.out
   

2. Check and verify the file permission.

   ls -lrt /usr/local/sbin/myscript.sh

3. Add execute permission(if it’s not already set).

   chmod +x /var/tmp/test_script.sh

Creating new systemd service unit

Create a new service unit file at /etc/systemd/system/sample.service with below content. The name of the service unit is user defined and can be any name of your choice.

`vi /etc/systemd/system/sample.service`


[Unit]
Description=Description for sample script goes here
After=network.target

[Service]
Type=simple
ExecStart=/var/tmp/test_script.sh
TimeoutStartSec=0

[Install]
WantedBy=default.target

After= : If the script needs any other system facilities (networking, etc), modify the [Unit] section to include appropriate After=, Wants=, or Requires= directives. Type= : Switch Type=simple for Type=idle in the [Service] section to delay execution of the script until all other jobs are dispatched WantedBy= : target to run the sample script in

Enable the systemd service unit

1. Reload the systemd process to consider newly created sample.service OR every time when sample.service gets modified.

   systemctl daemon-reload

2. Enable this service to start after reboot automatically.

   systemctl enable sample.service

3. Start the service.

   systemctl start sample.service

4. Reboot the host to verify whether the scripts are starting as expected during system boot.

   systemctl reboot

Deployment on Windows platform

• https://github.com/dotnet-architecture/eShopOnContainers
• https://github.com/dotnet-architecture/eShopOnContainers/wiki/Windows-setup

Resolve issue on login related to CORS rules

Use url http://docker.for.win.localhost:5100/ instead of http://localhost:5100

• https://github.com/dotnet-architecture/eShopOnContainers/issues/673