Kubernetes, also known as K8s, is an open-source system for automating deployment, scaling, and management of containerized applications.
Notice The initial blog post is here: blog post
- Prerequisites
- Git Terraform Code for the kubernetes cluster
- Control-Plane Node
- Ports on the control-plane node
- Firewall on the control-plane node
- Hosts file in the control-plane node
- No Swap on the control-plane node
- Kernel modules on the control-plane node
- NeedRestart on the control-plane node
- Installing a Container Runtime on the control-plane node
- Installing kubeadm, kubelet and kubectl on the control-plane node
- Initializing the control-plane node
- Create user access config to the k8s control-plane node
- Verify the control-plane node
- Install an overlay network provider on the control-plane node
- Verify CoreDNS is running on the control-plane node
- Worker Nodes
- Ports on the worker nodes
- Firewall on the worker nodes
- Hosts file in the worker node
- No Swap on the worker node
- Kernel modules on the worker node
- NeedRestart on the worker node
- Installing a Container Runtime on the worker node
- Installing kubeadm, kubelet and kubectl on the worker node
- Get Token from the control-plane node
- Get Certificate Hash from the control-plane node
- Join Workers to the kubernetes cluster
- Is the kubernetes cluster running ?
- Kubernetes Dashboard
- Nginx App
- That's it !
In this blog post, I'll try to share my personal notes on how to setup a kubernetes cluster with kubeadm on ubuntu 22.04 LTS Virtual Machines.
I am going to use three (3) Virtual Machines in my local lab. My home lab is based on libvirt Qemu/KVM (Kernel-based Virtual Machine) and I run Terraform as the infrastructure provision tool.
- at least 3 Virtual Machines of Ubuntu 22.04 (one for control-plane, two for worker nodes)
- 2GB (or more) of RAM on each Virtual Machine
- 2 CPUs (or more) on each Virtual Machine
- 20Gb of hard disk on each Virtual Machine
- No SWAP partition/image/file on each Virtual Machine
I prefer to have a reproducible infrastructure, so I can very fast create and destroy my test lab. My preferable way of doing things is testing on each step, so I pretty much destroy everything, coping and pasting commands and keep on. I use terraform for the create the infrastructure. You can find the code for the entire kubernetes cluster here: k8s cluster - Terraform code.
If you do not use terraform, skip this step!
You can git clone the repo to review and edit it according to your needs.
git clone https://github.com/ebal/k8s_cluster.git
cd tf_libvirt
You will need to make appropriate changes. Open Variables.tf for that. The most important option to change, is the User option. Change it to your github username and it will download and setup the VMs with your public key, instead of mine!
But pretty much, everything else should work out of the box. Change the vmem and vcpu settings to your needs.
Init terraform before running the below shell script. This action will download in your local directory all the required teffarorm providers or modules.
terraform init
Before going forward with spawning the VMs, we need to have the ubuntu 22.04 image on our system, or change the code to get it from the internet.
In Variables.tf terraform file, you will notice the below entries
# The image source of the VM
# cloud_image = "https://cloud-images.ubuntu.com/jammy/current/focal-server-cloudimg-amd64.img"
cloud_image = "../jammy-server-cloudimg-amd64.img"
If you do not want to download the Ubuntu 22.04 cloud server image then make the below change
# The image source of the VM
cloud_image = "https://cloud-images.ubuntu.com/jammy/current/focal-server-cloudimg-amd64.img"
#cloud_image = "../jammy-server-cloudimg-amd64.img"
otherwise you need to download it, in the upper directory, to speed things up
cd ../
curl -sLO https://cloud-images.ubuntu.com/jammy/current/jammy-server-cloudimg-amd64.img
cd -
ls -l ../jammy-server-cloudimg-amd64.img
We are ready to spawn our 3 VMs by running terraform plan & terraform apply
./start.sh
output should be something like:
...
Apply complete! Resources: 16 added, 0 changed, 0 destroyed.
Outputs:
VMs = [
"192.168.122.169 k8scpnode",
"192.168.122.40 k8wrknode1",
"192.168.122.8 k8wrknode2",
]
Verify that you have ssh access to the VMs
eg.
ssh -l ubuntu 192.168.122.169
replace the IP with what the output gave you.
DISCLAIMER if something failed, destroy everything with ./destroy.sh to remove any garbages before run ./start.sh again !!!
Let's us now start the configure of the k8s control-plane node.
Kubernetes runs a few services that needs to be accessable from the worker nodes.
| Protocol | Direction | Port Range | Purpose | Used By |
|---|---|---|---|---|
| TCP | Inbound | 6443 | Kubernetes API server | All |
| TCP | Inbound | 2379-2380 | etcd server client API | kube-apiserver, etcd |
| TCP | Inbound | 10250 | Kubelet API | Self, Control plane |
| TCP | Inbound | 10259 | kube-scheduler | Self |
| TCP | Inbound | 10257 | kube-controller-manager | Self |
Although etcd ports are included in control plane section, you can also host your own etcd cluster externally or on custom ports.
We need to open the necessary ports on the CP's (control-plane node) firewall.
sudo ufw allow 6443/tcp
sudo ufw allow 2379:2380/tcp
sudo ufw allow 10250/tcp
sudo ufw allow 10259/tcp
sudo ufw allow 10257/tcp
#sudo ufw disable
sudo ufw status
the output should be
To Action From
-- ------ ----
22/tcp ALLOW Anywhere
6443/tcp ALLOW Anywhere
2379:2380/tcp ALLOW Anywhere
10250/tcp ALLOW Anywhere
10259/tcp ALLOW Anywhere
10257/tcp ALLOW Anywhere
22/tcp (v6) ALLOW Anywhere (v6)
6443/tcp (v6) ALLOW Anywhere (v6)
2379:2380/tcp (v6) ALLOW Anywhere (v6)
10250/tcp (v6) ALLOW Anywhere (v6)
10259/tcp (v6) ALLOW Anywhere (v6)
10257/tcp (v6) ALLOW Anywhere (v6)
We need to update the /etc/hosts with the internal IP and hostname.
This will help when it is time to join the worker nodes.
echo $(hostname -I) $(hostname) | sudo tee -a /etc/hosts
Just a reminder: we need to update the hosts file to all the VMs. To include all the VMs' IPs and hostnames.
If you already know them, then your /etc/hosts file should look like this:
192.168.122.169 k8scpnode
192.168.122.40 k8wrknode1
192.168.122.8 k8wrknode2
replace the IPs to yours.
if you already the IPs of your VMs, run the below script to ALL 3 VMs
sudo tee -a /etc/hosts <<EOF
192.168.122.169 k8scpnode
192.168.122.40 k8wrknode1
192.168.122.8 k8wrknode2
EOF
Be sure that SWAP is disabled in all virtual machines!
sudo swapoff -a
and the fstab file should not have any swap entry.
The below command should return nothing.
sudo grep -i swap /etc/fstab
If not, edit the /etc/fstab and remove the swap entry.
If you follow my terraform k8s code example from the above github repo, you will notice that there isn't any swap entry in the cloud init (user-data) file.
Nevertheless it is always a good thing to douple check.
We need to load the below kernel modules on all k8s nodes, so k8s can create some network magic!
- overlay
- br_netfilter
Run the below bash snippet that will do that, and also will enable the forwarding features of the network.
sudo tee /etc/modules-load.d/kubernetes.conf <<EOF
overlay
br_netfilter
EOF
sudo modprobe overlay
sudo modprobe br_netfilter
sudo lsmod | grep netfilter
sudo tee /etc/sysctl.d/kubernetes.conf <<EOF
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_forward = 1
EOF
sudo sysctl --system
Before installing any software, we need to make a tiny change to needrestart program. This will help with the automation of installing packages and will stop asking -via dialog- if we would like to restart the services!
export -p NEEDRESTART_MODE="a"
a more permanent way, is to update the configuration file
echo "\$nrconf{restart} = 'a';" | sudo tee -a /etc/needrestart/needrestart.conf
It is time to choose which container runtime we are going to use on our k8s cluster. There are a few container runtimes for k8s and in the past docker were used to. Nowadays the most common runtime is the containerd that can also uses the cgroup v2 kernel features. There is also a docker-engine runtime via CRI. Read here for more details on the subject.
curl -sL https://download.docker.com/linux/ubuntu/gpg | sudo gpg --dearmor -o /etc/apt/trusted.gpg.d/docker-keyring.gpg
sudo apt-add-repository -y "deb https://download.docker.com/linux/ubuntu jammy stable"
sleep 5
sudo apt -y install containerd.io
containerd config default \
| sed 's/SystemdCgroup = false/SystemdCgroup = true/' \
| sudo tee /etc/containerd/config.toml
sudo systemctl restart containerd.service
We have also enabled the
systemd cgroup driver
so the control-plane node can use the cgroup v2 features.
Install the kubernetes packages (kubedam, kubelet and kubectl) by first adding the k8s repository on our virtual machine. To speed up the next step, we will also download the configuration container images.
sudo curl -sLo /etc/apt/trusted.gpg.d/kubernetes-keyring.gpg https://packages.cloud.google.com/apt/doc/apt-key.gpg
sudo apt-add-repository -y "deb http://apt.kubernetes.io/ kubernetes-xenial main"
sleep 5
sudo apt install -y kubelet kubeadm kubectl
sudo kubeadm config images pull
We can now initialize our control-plane node for our kubernetes cluster.
There are a few things we need to be careful about:
- We can specify the control-plane-endpoint if we are planning to have a high available k8s cluster. (we will skip this for now),
- Choose a Pod network add-on (next section) but be aware that CoreDNS (DNS and Service Discovery) will not run till then (later),
- define where is our container runtime socket (we will skip it)
- advertise the API server (we will skip it)
But we will define our Pod Network CIDR to the default value of the Pod network add-on so everything will go smoothly later on.
sudo kubeadm init --pod-network-cidr=10.244.0.0/16
Keep the output in a notepad.
Our k8s control-plane node is running, so we need to have credentials to access it.
The kubectl reads a configuration file (that has the token), so we copying this from k8s admin.
rm -rf $HOME/.kube
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config
ls -la $HOME/.kube/config
alias k="kubectl"
Verify that the kubernets is running.
That means we have a k8s cluster - but only the control-plane node is running.
kubectl cluster-info
#kubectl cluster-info dump
k get nodes -o wide; k get pods -A -o wide
As I mentioned above, in order to use the DNS and Service Discovery services in the kubernetes (CoreDNS) we need to install a Container Network Interface (CNI) based Pod network add-on so that your Pods can communicate with each other.
We will use flannel as the simplest of them.
k apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
Verify that the control-plane node is Up & Running and the control-plane pods (as coredns pods) are also running
k get nodes -o wide
NAME STATUS ROLES AGE VERSION INTERNAL-IP EXTERNAL-IP OS-IMAGE KERNEL-VERSION CONTAINER-RUNTIME
k8scpnode Ready control-plane 54s v1.25.0 192.168.122.169 <none> Ubuntu 22.04.1 LTS 5.15.0-46-generic containerd://1.6.8
k get pods -A -o wide
NAMESPACE NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
kube-flannel kube-flannel-ds-zqv2b 1/1 Running 0 36s 192.168.122.169 k8scpnode <none> <none>
kube-system coredns-565d847f94-lg54q 1/1 Running 0 38s 10.244.0.2 k8scpnode <none> <none>
kube-system coredns-565d847f94-ms8zk 1/1 Running 0 38s 10.244.0.3 k8scpnode <none> <none>
kube-system etcd-k8scpnode 1/1 Running 0 50s 192.168.122.169 k8scpnode <none> <none>
kube-system kube-apiserver-k8scpnode 1/1 Running 0 50s 192.168.122.169 k8scpnode <none> <none>
kube-system kube-controller-manager-k8scpnode 1/1 Running 0 50s 192.168.122.169 k8scpnode <none> <none>
kube-system kube-proxy-pv7tj 1/1 Running 0 39s 192.168.122.169 k8scpnode <none> <none>
kube-system kube-scheduler-k8scpnode 1/1 Running 0 50s 192.168.122.169 k8scpnode <none> <none>
That's it with the control-plane node !
The below instructions works pretty much the same on both worker nodes.
I will document the steps for the worker1 node but do the same for the worker2 node.
As we learned above on the control-plane section, kubernetes runs a few services
| Protocol | Direction | Port Range | Purpose | Used By |
|---|---|---|---|---|
| TCP | Inbound | 10250 | Kubelet API | Self, Control plane |
| TCP | Inbound | 30000-32767 | NodePort Services | All |
so we need to open the necessary ports on the worker nodes too.
sudo ufw allow 10250/tcp
sudo ufw allow 30000:32767/tcp
sudo ufw status
output should look like
To Action From
-- ------ ----
22/tcp ALLOW Anywhere
10250/tcp ALLOW Anywhere
30000:32767/tcp ALLOW Anywhere
22/tcp (v6) ALLOW Anywhere (v6)
10250/tcp (v6) ALLOW Anywhere (v6)
30000:32767/tcp (v6) ALLOW Anywhere (v6)
The next few steps are pretty much exactly the same as in the control-plane node. In order to keep this documentation short, I'll just copy/paste the commands.
Update the /etc/hosts file to include the IPs and hostname of all VMs.
192.168.122.169 k8scpnode
192.168.122.40 k8wrknode1
192.168.122.8 k8wrknode2
sudo swapoff -a
sudo tee /etc/modules-load.d/kubernetes.conf <<EOF
overlay
br_netfilter
EOF
sudo modprobe overlay
sudo modprobe br_netfilter
sudo lsmod | grep netfilter
sudo tee /etc/sysctl.d/kubernetes.conf <<EOF
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_forward = 1
EOF
sudo sysctl --system
export -p NEEDRESTART_MODE="a"
curl -sL https://download.docker.com/linux/ubuntu/gpg | sudo gpg --dearmor -o /etc/apt/trusted.gpg.d/docker-keyring.gpg
sudo apt-add-repository -y "deb https://download.docker.com/linux/ubuntu jammy stable"
sleep 5
sudo apt -y install containerd.io
containerd config default \
| sed 's/SystemdCgroup = false/SystemdCgroup = true/' \
| sudo tee /etc/containerd/config.toml
sudo systemctl restart containerd.service
sudo curl -sLo /etc/apt/trusted.gpg.d/kubernetes-keyring.gpg https://packages.cloud.google.com/apt/doc/apt-key.gpg
sudo apt-add-repository -y "deb http://apt.kubernetes.io/ kubernetes-xenial main"
sleep 5
sudo apt install -y kubelet kubeadm kubectl
To join nodes to the kubernetes cluster, we need to have a couple of things.
- a token from control-plane node
- the CA certificate hash from the contol-plane node.
If you didnt keep the output the initialization of the control-plane node, that's okay.
Run the below command in the control-plane node.
sudo kubeadm token list
and we will get the initial token that expires after 24hours.
TOKEN TTL EXPIRES USAGES DESCRIPTION EXTRA GROUPS
zt36bp.uht4cziweef1jo1h 23h 2022-08-31T18:38:16Z authentication,signing The default bootstrap token generated by 'kubeadm init'. system:bootstrappers:kubeadm:default-node-token
In this case is the
zt36bp.uht4cziweef1jo1h
To get the CA certificate hash from the control-plane-node, we need to run a complicated command:
openssl x509 -pubkey -in /etc/kubernetes/pki/ca.crt | openssl rsa -pubin -outform der 2>/dev/null | openssl dgst -sha256 -hex | sed 's/^.* //'
and in my k8s cluster is:
a4833f8c82953370610efaa5ed93b791337232c3a948b710b2435d747889c085So now, we can Join our worker nodes to the kubernetes cluster. Run the below command on both worker nodes:
sudo kubeadm join 192.168.122.169:6443 \
--token zt36bp.uht4cziweef1jo1h \
--discovery-token-ca-cert-hash sha256:a4833f8c82953370610efaa5ed93b791337232c3a948b710b2435d747889c085
we get this message
Run 'kubectl get nodes' on the control-plane to see this node join the cluster.
We can verify that
kubectl get nodes -o wide
kubectl get pods -A -o wide
NAME STATUS ROLES AGE VERSION INTERNAL-IP EXTERNAL-IP OS-IMAGE KERNEL-VERSION CONTAINER-RUNTIME
k8scpnode Ready control-plane 64m v1.25.0 192.168.122.169 <none> Ubuntu 22.04.1 LTS 5.15.0-46-generic containerd://1.6.8
k8wrknode1 Ready <none> 2m32s v1.25.0 192.168.122.40 <none> Ubuntu 22.04.1 LTS 5.15.0-46-generic containerd://1.6.8
k8wrknode2 Ready <none> 2m28s v1.25.0 192.168.122.8 <none> Ubuntu 22.04.1 LTS 5.15.0-46-generic containerd://1.6.8NAMESPACE NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
kube-flannel kube-flannel-ds-52g92 1/1 Running 0 2m32s 192.168.122.40 k8wrknode1 <none> <none>
kube-flannel kube-flannel-ds-7qlm7 1/1 Running 0 2m28s 192.168.122.8 k8wrknode2 <none> <none>
kube-flannel kube-flannel-ds-zqv2b 1/1 Running 0 64m 192.168.122.169 k8scpnode <none> <none>
kube-system coredns-565d847f94-lg54q 1/1 Running 0 64m 10.244.0.2 k8scpnode <none> <none>
kube-system coredns-565d847f94-ms8zk 1/1 Running 0 64m 10.244.0.3 k8scpnode <none> <none>
kube-system etcd-k8scpnode 1/1 Running 0 64m 192.168.122.169 k8scpnode <none> <none>
kube-system kube-apiserver-k8scpnode 1/1 Running 0 64m 192.168.122.169 k8scpnode <none> <none>
kube-system kube-controller-manager-k8scpnode 1/1 Running 1 (12m ago) 64m 192.168.122.169 k8scpnode <none> <none>
kube-system kube-proxy-4khw6 1/1 Running 0 2m32s 192.168.122.40 k8wrknode1 <none> <none>
kube-system kube-proxy-gm27l 1/1 Running 0 2m28s 192.168.122.8 k8wrknode2 <none> <none>
kube-system kube-proxy-pv7tj 1/1 Running 0 64m 192.168.122.169 k8scpnode <none> <none>
kube-system kube-scheduler-k8scpnode 1/1 Running 1 (12m ago) 64m 192.168.122.169 k8scpnode <none> <none>
That's it !
Our k8s cluster is running.
is a general purpose, web-based UI for Kubernetes clusters. It allows users to manage applications running in the cluster and troubleshoot them, as well as manage the cluster itself.
We can proceed by installing a k8s dashboard to our k8s cluster.
One simple way to install the kubernetes-dashboard, is by applying the latest (as of this writing) yaml configuration file.
kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/v2.6.1/aio/deploy/recommended.yaml
the output of the above command should be something like
namespace/kubernetes-dashboard created
serviceaccount/kubernetes-dashboard created
service/kubernetes-dashboard created
secret/kubernetes-dashboard-certs created
secret/kubernetes-dashboard-csrf created
secret/kubernetes-dashboard-key-holder created
configmap/kubernetes-dashboard-settings created
role.rbac.authorization.k8s.io/kubernetes-dashboard created
clusterrole.rbac.authorization.k8s.io/kubernetes-dashboard created
rolebinding.rbac.authorization.k8s.io/kubernetes-dashboard created
clusterrolebinding.rbac.authorization.k8s.io/kubernetes-dashboard created
deployment.apps/kubernetes-dashboard created
service/dashboard-metrics-scraper created
deployment.apps/dashboard-metrics-scraper created
Verify the installation
kubectl get all -n kubernetes-dashboard
NAME READY STATUS RESTARTS AGE
pod/dashboard-metrics-scraper-64bcc67c9c-kvll7 1/1 Running 0 2m16s
pod/kubernetes-dashboard-66c887f759-rr4gn 1/1 Running 0 2m16s
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/dashboard-metrics-scraper ClusterIP 10.110.25.61 <none> 8000/TCP 2m16s
service/kubernetes-dashboard ClusterIP 10.100.65.122 <none> 443/TCP 2m16s
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/dashboard-metrics-scraper 1/1 1 1 2m16s
deployment.apps/kubernetes-dashboard 1/1 1 1 2m16s
NAME DESIRED CURRENT READY AGE
replicaset.apps/dashboard-metrics-scraper-64bcc67c9c 1 1 1 2m16s
replicaset.apps/kubernetes-dashboard-66c887f759 1 1 1 2m16s
Kubernetes Dashboard by default runs on a internal 10.x.x.x IP.
To access the dashboard we need to have a NodePort in the kubernetes-dashboard service.
We can either Patch the service or edit the yaml file.
Choose one of these two ways, do not run both of them (unnecessary - not harmful)
This is one way to add a NodePort.
kubectl --namespace kubernetes-dashboard patch svc kubernetes-dashboard -p '{"spec": {"type": "NodePort"}}'
output
service/kubernetes-dashboard patched
verify the service
kubectl get svc -n kubernetes-dashboard
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
dashboard-metrics-scraper ClusterIP 10.110.25.61 <none> 8000/TCP 11m
kubernetes-dashboard NodePort 10.100.65.122 <none> 443:32709/TCP 11m
we can see the 30480 in the kubernetes-dashboard.
This is an alternative way to add a NodePort.
kubectl edit svc -n kubernetes-dashboard kubernetes-dashboard
and chaning the service type from
type: ClusterIPto
type: NodePortThe kubernetes-dashboard has two (2) pods, one (1) for metrics, one (2) for the dashboard.
To access the dashboard, first we need to identify in which Node is running.
kubectl get pods -n kubernetes-dashboard -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
dashboard-metrics-scraper-64bcc67c9c-fs7pt 1/1 Running 0 2m43s 10.244.1.9 k8wrknode1 <none> <none>
kubernetes-dashboard-66c887f759-pzt4z 1/1 Running 0 2m44s 10.244.2.9 k8wrknode2 <none> <none>
In my setup the dashboard pod is running on the worker node 2 and from the /etc/hosts is on the 192.168.122.8 IP.
The NodePort is 32709
k get svc -n kubernetes-dashboard -o wide
So, we can open a new tab on our browser and type:
https://192.168.122.8:32709
and accept the self-signed certificate!
Last step for the kubernetes-dashboard is to create an authentication token.
Create a new yaml file, with kind: ServiceAccount that has access to kubernetes-dashboard namespace and has name: admin-user.
cat > kubernetes-dashboard.ServiceAccount.yaml <<EOF
apiVersion: v1
kind: ServiceAccount
metadata:
name: admin-user
namespace: kubernetes-dashboard
EOF
add this service account to the k8s cluster
kubectl apply -f kubernetes-dashboard.ServiceAccount.yaml
output
serviceaccount/admin-user createdWe need to bind the Service Account with the kubernetes-dashboard via Role-based access control.
cat > kubernetes-dashboard.ClusterRoleBinding.yaml <<EOF
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
name: admin-user
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: cluster-admin
subjects:
- kind: ServiceAccount
name: admin-user
namespace: kubernetes-dashboard
EOF
apply this yaml file
kubectl apply -f kubernetes-dashboard.ClusterRoleBinding.yaml
clusterrolebinding.rbac.authorization.k8s.io/admin-user created
That means, our Service Account User has all the necessary roles to access the kubernetes-dashboard.
Final step is to create/get a token for our user.
kubectl -n kubernetes-dashboard create token admin-user
eyJhbGciOiJSUzI1NiIsImtpZCI6Im04M2JOY2k1Yk1hbFBhLVN2cjA4X1pkdktXNldqWkR4bjB6MGpTdFgtVHcifQ.eyJhdWQiOlsiaHR0cHM6Ly9rdWJlcm5ldGVzLmRlZmF1bHQuc3ZjLmNsdXN0ZXIubG9jYWwiXSwiZXhwIjoxNjYxOTU2NDQ1LCJpYXQiOjE2NjE5NTI4NDUsImlzcyI6Imh0dHBzOi8va3ViZXJuZXRlcy5kZWZhdWx0LnN2Yy5jbHVzdGVyLmxvY2FsIiwia3ViZXJuZXRlcy5pbyI6eyJuYW1lc3BhY2UiOiJrdWJlcm5ldGVzLWRhc2hib2FyZCIsInNlcnZpY2VhY2NvdW50Ijp7Im5hbWUiOiJhZG1pbi11c2VyIiwidWlkIjoiN2M4OWIyZDktMGIwYS00ZDg4LTk2Y2EtZDU3NjhjOWU2ZGYxIn19LCJuYmYiOjE2NjE5NTI4NDUsInN1YiI6InN5c3RlbTpzZXJ2aWNlYWNjb3VudDprdWJlcm5ldGVzLWRhc2hib2FyZDphZG1pbi11c2VyIn0.RMRQkZZhcoC5vCvck6hKfqXJ4dfN4JoQyAaClHZvOMI6JgQZEfB2-_Qsh5MfFApJUEit-0TX9r3CzW3JqvB7dmpTPxUQvHK68r82WGveBVp1wF37UyXu_IzxiCQzpCWYr3GcVGAGZVBbhhqNYm765FV02ZA_khHrW3WpB80ikhm_TNLkOS6Llq2UiLFZyHHmjl5pwvGzT7YXZe8s-llZSgc0UenEwPG-82eE279oOy6r4_NltoV1HB3uu0YjUJPlkqAPnHuSfAA7-8A3XAAVHhRQvFPea1qZLc4-oD24AcU0FjWqDMILEyE8zaD2ci8zEQBMoxcf2qmj0wn9cfbZwQ
Add this token to the previous login page
eg. Cluster --> Nodes
Before finishing this blog post, I would also like to share how to install a simple nginx-app as it is customary to do such thing in every new k8s cluster.
But plz excuse me, I will not get into much details. You should be able to understand the below k8s commands.
kubectl create deployment nginx-app --image=nginx --replicas=2
deployment.apps/nginx-app createdkubectl get deployment nginx-app -o wideNAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR
nginx-app 2/2 2 2 64s nginx nginx app=nginx-appkubectl expose deployment nginx-app --type=NodePort --port=80
service/nginx-app exposedkubectl get svc nginx-app -o wide
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
nginx-app NodePort 10.98.170.185 <none> 80:31761/TCP 27s app=nginx-app
kubectl describe svc nginx-app
Name: nginx-app
Namespace: default
Labels: app=nginx-app
Annotations: <none>
Selector: app=nginx-app
Type: NodePort
IP Family Policy: SingleStack
IP Families: IPv4
IP: 10.98.170.185
IPs: 10.98.170.185
Port: <unset> 80/TCP
TargetPort: 80/TCP
NodePort: <unset> 31761/TCP
Endpoints: 10.244.1.10:80,10.244.2.10:80
Session Affinity: None
External Traffic Policy: Cluster
Events: <none>
curl http://192.168.122.8:31761
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
html { color-scheme: light dark; }
body { width: 35em; margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif; }
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>
<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>
<p><em>Thank you for using nginx.</em></p>
</body>
</html>
I hope you enjoyed this blog post.
-ebal
./destroy.sh...
libvirt_domain.domain-ubuntu["k8wrknode1"]: Destroying... [id=446cae2a-ce14-488f-b8e9-f44839091bce]
libvirt_domain.domain-ubuntu["k8scpnode"]: Destroying... [id=51e12abb-b14b-4ab8-b098-c1ce0b4073e3]
time_sleep.wait_for_cloud_init: Destroying... [id=2022-08-30T18:02:06Z]
libvirt_domain.domain-ubuntu["k8wrknode2"]: Destroying... [id=0767fb62-4600-4bc8-a94a-8e10c222b92e]
time_sleep.wait_for_cloud_init: Destruction complete after 0s
libvirt_domain.domain-ubuntu["k8wrknode1"]: Destruction complete after 1s
libvirt_domain.domain-ubuntu["k8scpnode"]: Destruction complete after 1s
libvirt_domain.domain-ubuntu["k8wrknode2"]: Destruction complete after 1s
libvirt_cloudinit_disk.cloud-init["k8wrknode1"]: Destroying... [id=/var/lib/libvirt/images/Jpw2Sg_cloud-init.iso;b8ddfa73-a770-46de-ad16-b0a5a08c8550]
libvirt_cloudinit_disk.cloud-init["k8wrknode2"]: Destroying... [id=/var/lib/libvirt/images/VdUklQ_cloud-init.iso;5511ed7f-a864-4d3f-985a-c4ac07eac233]
libvirt_volume.ubuntu-base["k8scpnode"]: Destroying... [id=/var/lib/libvirt/images/l5Rr1w_ubuntu-base]
libvirt_volume.ubuntu-base["k8wrknode2"]: Destroying... [id=/var/lib/libvirt/images/VdUklQ_ubuntu-base]
libvirt_cloudinit_disk.cloud-init["k8scpnode"]: Destroying... [id=/var/lib/libvirt/images/l5Rr1w_cloud-init.iso;11ef6bb7-a688-4c15-ae33-10690500705f]
libvirt_volume.ubuntu-base["k8wrknode1"]: Destroying... [id=/var/lib/libvirt/images/Jpw2Sg_ubuntu-base]
libvirt_cloudinit_disk.cloud-init["k8wrknode1"]: Destruction complete after 1s
libvirt_volume.ubuntu-base["k8wrknode2"]: Destruction complete after 1s
libvirt_cloudinit_disk.cloud-init["k8scpnode"]: Destruction complete after 1s
libvirt_cloudinit_disk.cloud-init["k8wrknode2"]: Destruction complete after 1s
libvirt_volume.ubuntu-base["k8wrknode1"]: Destruction complete after 1s
libvirt_volume.ubuntu-base["k8scpnode"]: Destruction complete after 2s
libvirt_volume.ubuntu-vol["k8wrknode1"]: Destroying... [id=/var/lib/libvirt/images/Jpw2Sg_ubuntu-vol]
libvirt_volume.ubuntu-vol["k8scpnode"]: Destroying... [id=/var/lib/libvirt/images/l5Rr1w_ubuntu-vol]
libvirt_volume.ubuntu-vol["k8wrknode2"]: Destroying... [id=/var/lib/libvirt/images/VdUklQ_ubuntu-vol]
libvirt_volume.ubuntu-vol["k8scpnode"]: Destruction complete after 0s
libvirt_volume.ubuntu-vol["k8wrknode2"]: Destruction complete after 0s
libvirt_volume.ubuntu-vol["k8wrknode1"]: Destruction complete after 0s
random_id.id["k8scpnode"]: Destroying... [id=l5Rr1w]
random_id.id["k8wrknode2"]: Destroying... [id=VdUklQ]
random_id.id["k8wrknode1"]: Destroying... [id=Jpw2Sg]
random_id.id["k8wrknode2"]: Destruction complete after 0s
random_id.id["k8scpnode"]: Destruction complete after 0s
random_id.id["k8wrknode1"]: Destruction complete after 0s
Destroy complete! Resources: 16 destroyed.