Deploy kubernetes cluster on 2 or more servers ; k8s on-premise

DRAFT

https://dzone.com/articles/kubespray-10-simple-steps-for-installing-a-product

get all yamls backup kubectl get po,deployment,rc,rs,ds,no,job -o yaml?

all actions under root.

make servers able to communicate cvia ssh with keys ,m like:

on master as root

ssh-keygen -t rsa -b 4096
ssh-copy-id root@<slaveIP>

on slave as root

ssh-keygen -t rsa -b 4096 
ssh-copy-id root@<masterIP>

on master rememebr to add /root/.ssh/id_rsa.pub content into /root/.ssh/authorized_keys

this will allow to connect master on himself, yeah this need if we start ansible from master 

master+slabve: yum upgrade disable selinux:

 setenforce 0
 sed -i --follow-symlinks 's/SELINUX=enforcing/SELINUX=disabled/g' /etc/sysconfig/selinux

stop and disable firewaal

systemctl stop firewalld
systemctl disable firewalld

ON master:

 #modprobe br_netfilter
 #echo '1' > /proc/sys/net/bridge/bridge-nf-call-iptables
 #sysctl -w net.ipv4.ip_forward=1

On Slave:

# echo '1' > /proc/sys/net/bridge/bridge-nf-call-iptables
# sysctl -w net.ipv4.ip_forward=1

next slave and master again:

 sudo yum install epel-release
 sudo yum install ansible

  dnf install python3

//// easy_install pip

pip3 install jinja2 --upgrade

on master install kubespay

git clone https://github.com/kubernetes-incubator/kubespray.git

cd kubespray
sudo pip install -r requirements.txt

Copy inventory/sample as inventory/ndicluster (change “ndisluter” to any name you want for the cluster)

cp -avr inventory/sample  inventory/ndicluster

Update the Ansible inventory file with inventory builder

declare -a IPS=( 213.108.199.13* 213.108.199.14*)
CONFIG_FILE=inventory/ndicluster/hosts.ini python3 contrib/inventory_builder/inventory.py ${IPS[@]}

check the hosts.ini ... it may be generation in differ variants but I;'ve put my to the next view:

[all]
node 1 ansible_host=213.108.199.13*  ip=213.108.199.13*  
node2 ansible_host=213.108.199.14*  ip=213.108.199.14*  

[kube-master]
node1 

[kube-node]
node1#should not be there!??
node2 

[etcd]
node1 

[k8s-cluster:children]
kube-master
kube-node 

[calico-rr]

[vault] #probably add!??
node1
node2

BETTER USE CENTOS7 !

ansible-playbook -i inventory/mycluster/hosts.ini cluster.yml

check

kubectl get pods -A

NOTE: if you like to reinstall you cluster you may do it with reset.yaml:

ansible-playbook -i inventory/ndicluster/hosts.ini reset.yml 

and install back after

---dashoboard----

references: #https://github.com/kubernetes/dashboard/blob/master/docs/user/access-control/creating-sample-user.md

           #https://kubernetes.io/docs/tasks/access-application-cluster/web-ui-dashboard/

Insecure way but will allow you to access dashboard quickly w/o proxy: allow dashboard access

kubectl create clusterrolebinding cluster-system-anonymous --clusterrole=cluster-admin --user=system:anonymous

create user

cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: ServiceAccount
metadata:
  name: admin-user
  namespace: kube-system
EOF

apply permissions

cat <<EOF | kubectl apply -f -
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: kube-system
EOF

get token:

kubectl -n kube-system describe secret $(kubectl -n kube-system get secret | grep admin-user | awk '{print $1}')

Login with token:

https://213.108.19*.*:6443/api/v1/namespaces/kube-system/services/https:kubernetes-dashboard:/proxy/#/overview?namespace=default

---HELM---

we will install helm exactly on our master node; but you may easily confifgure the kubectl and helm work from your PC

curl -fsSL -o get_helm.sh https://raw.githubusercontent.com/helm/helm/master/scripts/get-helm-3
chmod 700 get_helm.sh
./get_helm.sh

Init

helm init

Example install elasticsearch:

helm repo add elastic https://Helm.elastic.co
"elastic" has been added to your repositories

#optional: you may donwload helm chart and modify iot before apply or apply default from repo. whatever
#curl -O https://raw.githubusercontent.com/elastic/Helm-charts/master/elasticsearch/examples/minikube/values.yaml
#helm install --name elasticsearch elastic/elasticsearch -f ./values.yaml 

helm install --name elasticsearch elastic/elasticsearch