[Kubernetes] RedHat7 에서 Kubernetes설치하기

이번엔 쿠버네티스를 RedHat7에서 설치하는 법을 다룬다.
참고로 나는 RedHat7.9에서 처음 설치를 진행하다 안되서 RedHat7.7로 변경했다.

근데 7.9도 될거다.

우선 나의 VM 환경은 아래와 같다.

HOSTNAME	IP	ROLE	RESOURCE	Host OS
master	192.168.10.20	control-panel, master	Hard Disk(30G), 4GB RAM	Redhat7.7
worker1	192.168.10.21	worker1	Hard Disk(30G), 4GB RAM	Redhat7.7
worker2	192.168.10.22	worker2	Hard Disk(30G), 4GB RAM	Redhat7.7

ISO IMAGE

md5 : faa7d8dd79085ecae05b94e6180d9cbd

1. 환경 설정

# selinux 비활성화
setenforce 0
sed -i 's/^SELINUX=enforcing$/SELINUX=disabled/' /etc/selinux/config

# swap 비활성화
swapoff -a
sed -i '/ swap / s/^\(.*\)$/#\1/g' /etc/fstab

# firewalld 비활성화
systemctl disable firewalld
systemctl stop firewalld

# iptables 커널 설정
cat <<EOF>> /etc/modules-load.d/k8s.conf
br_netfilter
EOF

cat <<EOF>> /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF

sysctl --system

# hosts 설정
# hostnamectl set-hostname k8s-master
cat <<EOF >> /etc/hosts
192.168.10.20 master
192.168.10.21 worker1
192.168.10.22 worker2
EOF

yum update -y

2. Docker 설치

yum install -y http://mirror.centos.org/centos/7/extras/x86_64/Packages/slirp4netns-0.4.3-4.el7_8.x86_64.rpm
yum install -y http://mirror.centos.org/centos/7/extras/x86_64/Packages/fuse3-libs-3.6.1-4.el7.x86_64.rpm
yum install -y http://mirror.centos.org/centos/7/extras/x86_64/Packages/fuse3-devel-3.6.1-4.el7.x86_64.rpm
yum install -y http://mirror.centos.org/centos/7/extras/x86_64/Packages/fuse3-3.6.1-4.el7.x86_64.rpm
yum install -y http://mirror.centos.org/centos/7/extras/x86_64/Packages/fuse-overlayfs-0.7.2-6.el7_8.x86_64.rpm
yum install -y http://mirror.centos.org/centos/7/extras/x86_64/Packages/fuse-overlayfs-0.7.2-6.el7_8.x86_64.rpm
yum install -y http://mirror.centos.org/centos/7/extras/x86_64/Packages/container-selinux-2.119.2-1.911c772.el7_8.noarch.rpm
yum install -y lvm2 device-mapper device-mapper-persistent-data device-mapper-event device-mapper-libs device-mapper-event-libs
yum install -y wget
wget https://download.docker.com/linux/centos/docker-ce.repo -O /etc/yum.repos.d/docker-ce.repo

yum -y install docker-ce
systemctl start docker
systemctl enable docker

개인적으로 Docker 설치 부분에서 잘 안됬는데 삽질 끝에 결국 됬다.
이렇게 했는데도 안되는 경우는 특정 라이브러리가 설치되지 않아서 그럴거다.
그러면 저거 한줄한줄 설치해주고 안되면 그냥 RedHat 버전을 올리는게... ㅎㅎ

3. docker daemon.json 편집

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

service docker restart

4. Kubernetes 패키지 설치

yum install -y kubelet kubeadm kubectl --disableexcludes=kubernetes

4-1. Kubernetes Config

sed -i '/"cri"/ s/^/#/' /etc/containerd/config.toml
systemctl restart containerd

kubeadm init
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config

4-2. Kublet 실행

systemctl enable kubelet
systemctl start kubelet

5. 확인

kubeadm version -o short
kubectl version --short
kubelet --version

후기
설치하는데 삽질하고 싶진 않았는데.. ㅠㅠ
우분투가 편하긴 하더라고요..