# Microk8s: installation and configuration in CentOS 8

**URL:** <https://discuss.kubernetes.io/t/microk8s-installation-and-configuration-in-centos-8/14462>\
**Category:** microk8s\
**Tags:** docs\
**Created:** [January 13, 2021, 9:34pm UTC](https://discuss.kubernetes.io/t/microk8s-installation-and-configuration-in-centos-8/14462 "2021-01-13T21:34:12Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![srinijalagam](https://avatars.discourse-cdn.com/v4/letter/s/e36b37/32.png) [@srinijalagam](https://discuss.kubernetes.io/u/srinijalagam)\
**Post date:** [January 13, 2021, 9:34pm UTC](https://discuss.kubernetes.io/t/microk8s-installation-and-configuration-in-centos-8/14462/1 "2021-01-13T21:34:12Z")

</div>

Hi all, I have documented below steps part of my learning , thought of sharing to all.

**Installation and configuration in CentOS8**

**Prerequisites**

1. CentOS 8 .x

2. Visit [microk8s.io](http://microk8s.io) and get basic idea.

3. Resources required: 8GB RAM, 8xCPU and 400 GB storage. If you have more services and/or high data volume, consider increasing RAM and CPU cores

**Proxy settings**

**Note:** Do proxy settings only if required, - this depends on network and location of the system. Below is the right proxy per environment required:

**System level proxy:**

Edit the /etc/environments file and add the proxy to it  
http\_proxy=http://x.x.x.x:port

https\_proxy= [http://x.x.x](http://x.x.x).:port

**Snap package manger proxy:**

These required only if you are behind a proxy.  
sudo snap install microk8s –classic  
error: unable to contact snap store , in this case the proxy settings are required

sudo snap set system proxy.http=http://x.x.x.x:8080  
sudo snap set system proxy.https=http://x.x.x.x:8080

**containers proxy:**

sudo vi /var/snap/microk8s/current/args/containerd-env  
un comment HTPP\_PROXY and update with correct proxy  
HTTP\_PROXY= [http://x.x.x.x:8080](http://x.x.x.x:8080)  
HTTPS\_PROXY=http://x.x.x.x:8080

**Docker Proxy :** vi /etc/systemd/system/docker.service.d/http-proxy.conf  
[Service]  
Environment="HTTP\_PROXY=http://x.x.x.x:8080

**Installation**

_ **Step 1:** _ sudo yum update  
_ **Step2:** _ sudo yum install epel-release  
_ **Step 3:** _ yum update  
_ **Step 4:** _ sudo yum install snapd

_ **Step 5:** _ sudo systemctl enable --now snapd.socket  
_ **Step 5:** _ sudo ln -s /var/lib/snapd/snap /snap  
_ **Step 6:** _ sudo snap install microk8s –-classic

```
 output

2020-09-14T14:51:21Z INFO Waiting for automatic snapd restart...

Warning: /var/lib/snapd/snap/bin was not found in your $PATH. If you've not

restarted your session since you installed snapd, try doing that. Please

see https://forum.snapcraft.io/t/9469 for more details.

microk8s v1.19.0 from Canonical✓ installed

```

_ **Step7:** _ sudo usermod -a -G microk8s $USER  
_ **Step 8:** _ sudo chown -f -R $USER ~/.kub  
_ **Step 9:** _ reboot the VM to make sure all the configurations taken effect  
**Step 10** : check the status of installed microk8s microk8s.status

```
output

microk8s is running
high-availability: no
datastore master nodes: 127.0.0.1:19001
datastore standby nodes: none
addons:
enabled:
ha-cluster # Configure high availability on the current node
disabled:
ambassador # Ambassador API Gateway and Ingress
cilium # SDN, fast with full network policy
dashboard # The Kubernetes dashboard
dns # CoreDNS
fluentd # Elasticsearch-Fluentd-Kibana logging and monitoring
gpu # Automatic enablement of Nvidia CUDA
helm # Helm 2 - the package manager for Kubernetes
helm3 # Helm 3 - Kubernetes package manager
host-access # Allow Pods connecting to Host services smoothly
ingress # Ingress controller for external access
istio # Core Istio service mesh services
jaeger # Kubernetes Jaeger operator with its simple config
knative # The Knative framework on Kubernetes.
kubeflow # Kubeflow for easy ML deployments
linkerd # Linkerd is a service mesh for Kubernetes and other frameworks
metallb # Loadbalancer for your Kubernetes cluster
metrics-server # K8s Metrics Server for API access to service metrics
multus # Multus CNI enables attaching multiple network interfaces to pods
prometheus # Prometheus operator for monitoring and logging
rbac # Role-Based Access Control for authorisation
registry # Private image registry exposed on localhost:32000

```

_ **Step 11:** _ execute microk8s.kubectl get nodes

```
Output

NAME STATUS ROLES AGE VERSION
mk8s-dev-as Ready <none> 3m32s v1.19.0-34+1a52fbf0753680

```

_ **Step 12:** _ execute microk8s enable rbac dns ingress storage helm  
_ **Step13 :** _ check status by executing microk8s.status

```
Output

microk8s is running
high-availability: no
datastore master nodes: 127.0.0.1:19001
datastore standby nodes: none
addons:
enabled:
dns # CoreDNS
ha-cluster # Configure high availability on the current node
registry # Private image registry exposed on localhost:32000
storage # Storage class; allocates storage from host directory
ingress# ingress controller
helm # helm

**Note: before going forward make sure all of the above are showing in enabled status.**

```

_ **Step 14:** _ Disable the selenium edit /etc/selinux/config

This file controls the state of SELinux on the system.

SELINUX= can take one of these three values:

enforcing - SELinux security policy is enforced.

permissive - SELinux prints warnings instead of enforcing.

disabled - No SELinux policy is loaded.

SELINUX=disabled

SELINUXTYPE= can take one of these three values:

targeted - Targeted processes are protected,

minimum - Modification of targeted policy. Only selected processes are protected.

mls - Multi Level Security protection.

SELINUXTYPE=targeted

_ **Step 15:** _ sudo iptables -P FORWARD ACCEPT

_ **Step16:** _ microk8s helm init  
_ **Step 17** _ : Install docker and make these changes to MK8S to use docker runtime.  
In case docket not installed , first follow steps here [Install Docker Engine on CentOS | Docker Documentation](https://docs.docker.com/engine/install/centos/)

Then execute below a & b.

a) vi /var/snap/microk8s/current/args/kubelet

#–container-runtime=remote

#–container-runtime-endpoint=${SNAP\_COMMON}/run/containerd.sock

**–container-runtime=docker**

b) Add the following lines to /etc/docker/daemon.json: and restart docker

```
{

"insecure-registries" : ["localhost:32000"]

}

```

_ **Step18:** _ _Execute below commands to enable tiller pod access for everyone._

```
kubectl create serviceaccount --namespace kube-system tiller

kubectl create clusterrolebinding tiller-cluster-rule --clusterrole=cluster-admin --serviceaccount=kube-system:tiller

kubectl patch deploy --namespace kube-system tiller-deploy -p '{"spec":{"template":{"spec":{"serviceAccount":"tiller"}}}}'

```

**Step19** : Stop/start microk8s after above changes using snap stop microk8s and snap start microk8s commands.

**Step20**  **:** MK8S health check, execute below three commands and see all running or ready status

```
microk8s status

microk8s kubectl get node

microk8s kubectl get pod -A

```

**FINALLY do the following to just use kubectl and helm instead of microk8s.kubectl and microk8s.helm How to remove/reduce the prefix microk8s to all k8S and helm commands**

```
**Solution 1** : create aliases by following below commands

cd /var/lib/snapd/snap/bin

ln -s microk8s.kubectl kubectl

ln -s microk8s.helm helm

ln -s microk8s M

**Solution 2:**

In home home directory e.g /home/centos

Create “./bash_aliases” file with below commands

alias kubectl="microk8s kubectl"

alias helm="microk8s helm"

alias M="microk8s"

Make you sure to add an entry in user home directory “.bashrc” file as show below

# .bashrc

# Source global definitions

if [-f /etc/bashrc]; then

. /etc/bashrc

fi

# User specific environment

PATH="$HOME/.local/bin:$HOME/bin:$PATH"

export PATH

# Uncomment the following line if you don't like systemctl's auto-paging feature:

# export SYSTEMD_PAGER=

# User specific aliases and functions

**if [-f ~/.bash_aliases]; then**

**. ~/.bash_aliases**

**fi**

```

You can run kubectl/helm as normal without prefix microk8s from here

**Tips & Tricks**  
**kubectl logs command shows gateway timeout error.**

**Solution** : `check /etc/environment has any proxies configured. Comment out all and stop and start microk8s.`

**Enabling RBAC is causing error when we are bring up the application, Error: configmaps is forbidden: User “system:serviceaccount:kube-system:default” cannot list resource “configmaps” in API group “” in the namespace "kube-system"**

**Solution** : execute below commands

```
kubectl create serviceaccount --namespace kube-system tiller

kubectl create clusterrolebinding tiller-cluster-rule --clusterrole=cluster-admin --serviceaccount=kube-system:tiller
```