Deploying Kubernetes with RKE on Red Hat: A Guide for Medium-Sized Enterprises”
Rancher Kubernetes Engine (RKE) is a lightweight Kubernetes installer that simplifies the deployment and management of Kubernetes clusters. To install RKE on Red Hat Linux for a medium-sized cluster, you can follow these steps:
Note: This guide assumes that you have a Red Hat Linux server set up and ready to use.
Prerequisites for RKE All Nodes.
System OS Requirement and root privilege account.
- Redhat 8.5 (5 Nodes Based on your requirements).
- Root or sudo access on the server.
DNS mapping in k8s all hosts.
cat <<EOF | sudo tee -a /etc/hosts
192.168.200.10 master-01 master-01.example.com
192.168.200.11 master-02 master-02.example.com
192.168.200.12 master-03 master-03.example.com
192.168.200.30 worker-01 worker-01.example.com
192.168.200.31 worker-02 worker-02.example.com
EOF
Firewall allow following ports for each nodes.
[root@master01 ~]# firewall-cmd — add-port={22/tcp,80/tcp,2376/tcp,2379/tcp,2380/tcp,8472/tcp,9099/tcp,10250/tcp,6443/tcp,10254/tcp,30000–32767/tcp,30000–32767/udp} — permanent
success
[root@master01 ~]# firewall-cmd — reload
success
Selinux permissive mode for each nodes
sudo sed -i ‘s/SELINUX=enforcing/SELINUX=permissive/’ /etc/selinux/config
Configure required modules for each nodes
cat <<EOF | sudo tee /etc/modules-load.d/containerd.conf
overlay
br_netfilter
EOF
sudo modprobe overlay
sudo modprobe br_netfilter
sudo sed -i ‘s/^net.ipv4.ip_forward/#&/’ /etc/sysctl.d/*
cat <<EOF | sudo tee /etc/sysctl.d/99-kubernetes-cri.conf
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_forward = 1
net.bridge.bridge-nf-call-ip6tables = 1
net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1
EOF
sudo sysctl -p /etc/sysctl.d/99-kubernetes-cri.conf
Disable Swap for each nodes
sudo swapoff -a
sudo sed -i ‘s/^[^#]*swap/#&/’ /etc/fstab
Install Docker Engine (CE) for each nodes
sudo dnf install -y yum-utils device-mapper-persistent-data lvm2 iscsi-initiator-utils vim wget chrony
sudo dnf config-manager — add-repo=https://download.docker.com/linux/centos/docker-ce.repo
sudo dnf remove -y podman buildah
sudo dnf install -y docker-ce docker-ce-cli containerd.io
sudo usermod -a -G docker $USER
sudo systemctl enable docker — now
docker –version
sudo mkdir -p /etc/containerd
sudo containerd config default | sudo tee /etc/containerd/config.toml
sudo systemctl enable containerd –now
SSH setting for RKE mandatory requirement for each nodes
cat <<EOF | sudo tee -a /etc/ssh/sshd_config
AllowStreamLocalForwarding yes
PermitTunnel yes
EOF
sudo systemctl restart sshd
SSH Keygen generate and ssh-copy-id
- Login to the master nodes with ssh client.
ssh-keygen
ssh-copy-id k8s@master-01.example.com
ssh-copy-id k8s@master-02.example.com
ssh-copy-id k8s@master-03.example.com
ssh-copy-id k8s@worker-01.example.com
ssh-copy-id k8s@worker-02.example.com
Download the RKE on master node
wget https://github.com/rancher/rke/releases/download/v1.17.5/rke_linux-amd64
sudo install -o root -g root -m 0755 rke_linux-amd64 /usr/bin/rke
rke — version
Download the kubectl on master node
curl -LO “https://dl.k8s.io/release/$(curl -L -s https://dl.k8s.io/release/stable.txt)/bin/linux/amd64/kubectl"
sudo install -o root -g root -m 0755 kubectl /usr/bin/kubectl
kubectl version — client –short
SSH tunnel testing on k8s Nodes
ssh -i ~/.ssh/id_rsa k8s@master-01 docker version
ssh -i ~/.ssh/id_rsa k8s@master-02 docker version
ssh -i ~/.ssh/id_rsa k8s@master-03 docker version
ssh -i ~/.ssh/id_rsa k8s@worker-01 docker version
ssh -i ~/.ssh/id_rsa k8s@worker-02 docker version
Building the RKE cluster
rke config
[rke@master01 ~]$ rke config
[+] Cluster Level SSH Private Key Path [~/.ssh/id_rsa]: /home/k8s/.ssh/id_rsa
[+] Number of Hosts [1]: 5
[+] SSH Address of host (1) [none]: master01
[+] SSH Port of host (1) [22]:
[+] SSH Private Key Path of host (master01) [none]: /home/k8s/.ssh/id_rsa
[+] SSH User of host (master01) [redhat]: k8s
[+] Is host (master01) a Control Plane host (y/n)? [y]:
[+] Is host (master01) a Worker host (y/n)? [n]:
[+] Is host (master01) an etcd host (y/n)? [n]: y
[+] Override Hostname of host (master01) [none]:
[+] Internal IP of host (master01) [none]:
[+] Docker socket path on host (master01) [/var/run/docker.sock]:
[+] SSH Address of host (2) [none]: master02
[+] SSH Port of host (2) [22]:
[+] SSH Private Key Path of host (master02) [none]: /home/k8s/.ssh/id_rsa
[+] SSH User of host (master02) [redhat]: k8s
[+] Is host (master02) a Control Plane host (y/n)? [y]: y
[+] Is host (master02) a Wok8sr host (y/n)? [n]: n
[+] Is host (master02) an etcd host (y/n)? [n]: y
[+] Override Hostname of host (master02) [none]:
[+] Internal IP of host (master02) [none]:
[+] Docker socket path on host (master02) [/var/run/docker.sock]:
[+] SSH Address of host (3) [none]: master03
[+] SSH Port of host (3) [22]:
[+] SSH Private Key Path of host (master03) [none]: /home/k8s/.ssh/id_rsa
[+] SSH User of host (master03) [redhat]: k8s
[+] Is host (master03) a Control Plane host (y/n)? [y]: y
[+] Is host (master03) a Wok8sr host (y/n)? [n]: n
[+] Is host (master03) an etcd host (y/n)? [n]: y
[+] Override Hostname of host (master03) [none]:
[+] Internal IP of host (master03) [none]:
[+] Docker socket path on host (master03) [/var/run/docker.sock]:
[+] SSH Address of host (4) [none]: worker01
[+] SSH Port of host (4) [22]:
[+] SSH Private Key Path of host (worker01) [none]: /home/k8s/.ssh/id_rsa
[+] SSH User of host (worker01) [redhat]: k8s
[+] Is host (worker01) a Control Plane host (y/n)? [y]: n
[+] Is host (worker01) a Wok8sr host (y/n)? [n]: y
[+] Is host (worker01) an etcd host (y/n)? [n]: n
[+] Override Hostname of host (worker01) [none]:
[+] Internal IP of host (worker01) [none]:
[+] Docker socket path on host (worker01) [/var/run/docker.sock]:
[+] SSH Address of host (5) [none]: worker02
[+] SSH Port of host (5) [22]:
[+] SSH Private Key Path of host (worker02) [none]: /home/k8s/.ssh/id_rsa
[+] SSH User of host (worker02) [redhat]: k8s
[+] Is host (worker02) a Control Plane host (y/n)? [y]: n
[+] Is host (worker02) a Wok8sr host (y/n)? [n]: y
[+] Is host (worker02) an etcd host (y/n)? [n]: n
[+] Override Hostname of host (worker02) [none]:
[+] Internal IP of host (worker02) [none]:
[+] Docker socket path on host (worker02) [/var/run/docker.sock]:
[+] Network Plugin Type (flannel, calico, weave, canal) [calico]:
[+] Authentication Strategy [x509]:
[+] Authorization Mode (rbac, none) [rbac]:
[+] Kubernetes Docker image [rancher/hyperkube:v1.17.5-rancher1]:
[+] Cluster domain [cluster.local]:
[+] Service Cluster IP Range [10.43.0.0/16]:
[+] Enable PodSecurityPolicy [n]:
[+] Cluster Network CIDR [10.42.0.0/16]:
[+] Cluster DNS Service IP [10.43.0.10]:
[+] Add addon manifest URLs or YAML files [no]:rke up
[rke@master01 ~]$ rke up
INFO[0000] Running RKE version: v1.0.8
INFO[0000] Initiating Kubernetes cluster
INFO[0000] [dialer] Setup tunnel for host [master01]
INFO[0000] [dialer] Setup tunnel for host [master02]
INFO[0000] [dialer] Setup tunnel for host [master03]
INFO[0000] [dialer] Setup tunnel for host [worker01]
INFO[0000] [dialer] Setup tunnel for host [worker02]
...
INFO[0379] [ingress] Setting up nginx ingress controller
INFO[0379] [addons] Saving ConfigMap for addon rke-ingress-controller to Kubernetes
INFO[0379] [addons] Successfully saved ConfigMap for addon rke-ingress-controller to Kubernetes
INFO[0379] [addons] Executing deploy job rke-ingress-controller
INFO[0384] [ingress] ingress controller nginx deployed successfully
INFO[0384] [addons] Setting up user addons
INFO[0384] [addons] no user addons defined
INFO[0384] Finished building Kubernetes cluster successfullyKube config setting up
mkdir ~/.kube
cp kube_config_cluster.yml ~/.kube/config
Kube config setting up
kubectl labels nodes master-01.example.com node=master-01
kubectl labels nodes master-02.example.com node=master-02
kubectl labels nodes master-03.example.com node=master-03
kubectl labels nodes worker-01.example.com node=worker-01
kubectl labels nodes worker-02.example.com node=worker-02
kubectl get nodes
NAME STATUS ROLES AGE VERSION
master01 Ready controlplane,etcd. 5m34s v1.17.5
master02 Ready controlplane,etcd. 5m34s v1.17.5
master03 Ready controlplane,etcd. 5m34s v1.17.5
worker01 Ready worker 5m34s v1.17.5
worker02 Ready worker 5m34s v1.17.5Will be continue for K8s components in next series.
