kubernetes/Install hardway
[HARDWAY] 09.Bootstrapping the Kubernetes Worker Nodes
겸겸사
2020. 12. 2. 18:11
https://github.com/kelseyhightower/kubernetes-the-hard-way/blob/master/docs/09-bootstrapping-kubernetes-workers.md
### Provisioning a Kubernetes Worker Node
# Pre ENV
service firewalld stop
systemctl disable firewalld
iptables -L
yum install -y wget
yum install -y bind-utils
sed -i 's/SELINUX=enforcing/SELINUX=disabled/g' /etc/sysconfig/selinux
sed -i 's/SELINUX=enforcing/SELINUX=disabled/g' /etc/selinux/config
setenforce 0
# Install the OS dependencies:
yum -y install socat conntrack ipset
# Disable Swap
kubelet 은 swap 이 활설화 되어있는경우 동작하지 않음
swapon --show
swapoff -a
[root@worker01 ~]# cat /etc/fstab
#
# /etc/fstab
# Created by anaconda on Fri Nov 13 16:49:56 2020
#
# Accessible filesystems, by reference, are maintained under '/dev/disk'
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info
#
/dev/mapper/centos-root / xfs defaults 0 0
UUID=1e96ed00-419d-481d-baaf-b43b7ef7c3bb /boot xfs defaults 0 0
#/dev/mapper/centos-swap swap swap defaults 0 0
# /etc/fstab 을 수정해야한다. sed 로 해도 되지만 fstab 은 위험도가 높은 파일이니 손으로 주석처리 해주자
#/dev/mapper/centos-swap swap swap defaults 0 0
# Download and Install Worker Binaries
wget \
https://github.com/kubernetes-sigs/cri-tools/releases/download/v1.18.0/crictl-v1.18.0-linux-amd64.tar.gz \
https://github.com/opencontainers/runc/releases/download/v1.0.0-rc91/runc.amd64 \
https://github.com/containernetworking/plugins/releases/download/v0.8.6/cni-plugins-linux-amd64-v0.8.6.tgz \
https://github.com/containerd/containerd/releases/download/v1.3.6/containerd-1.3.6-linux-amd64.tar.gz \
https://storage.googleapis.com/kubernetes-release/release/v1.18.6/bin/linux/amd64/kubectl \
https://storage.googleapis.com/kubernetes-release/release/v1.18.6/bin/linux/amd64/kube-proxy \
https://storage.googleapis.com/kubernetes-release/release/v1.18.6/bin/linux/amd64/kubelet
sudo mkdir -p \
/etc/cni/net.d \
/opt/cni/bin \
/var/lib/kubelet \
/var/lib/kube-proxy \
/var/lib/kubernetes \
/var/run/kubernetes
mkdir containerd
tar -xvf crictl-v1.18.0-linux-amd64.tar.gz
tar -xvf containerd-1.3.6-linux-amd64.tar.gz -C containerd
tar -xvf cni-plugins-linux-amd64-v0.8.6.tgz -C /opt/cni/bin/
mv runc.amd64 runc
chmod +x crictl kubectl kube-proxy kubelet runc
mv crictl kubectl kube-proxy kubelet runc /usr/local/bin/
mv containerd/bin/* /bin/
### Configure CNI Networking
# Create the bridge network configuration file:
cat <<EOF | sudo tee /etc/cni/net.d/10-bridge.conf
{
"cniVersion": "0.3.1",
"name": "bridge",
"type": "bridge",
"bridge": "cnio0",
"isGateway": true,
"ipMasq": true,
"ipam": {
"type": "host-local",
"ranges": [
[{"subnet": "10.200.0.0/16"}]
],
"routes": [{"dst": "0.0.0.0/0"}]
}
}
EOF
# Create the loopback network configuration file:
cat <<EOF | sudo tee /etc/cni/net.d/99-loopback.conf
{
"cniVersion": "0.3.1",
"name": "lo",
"type": "loopback"
}
EOF
### Configure containerd
mkdir -p /etc/containerd/
cat << EOF | sudo tee /etc/containerd/config.toml
[plugins]
[plugins.cri.containerd]
snapshotter = "overlayfs"
[plugins.cri.containerd.default_runtime]
runtime_type = "io.containerd.runtime.v1.linux"
runtime_engine = "/usr/local/bin/runc"
runtime_root = ""
EOF
# Create the containerd.service systemd unit file:
cat <<EOF | sudo tee /etc/systemd/system/containerd.service
[Unit]
Description=containerd container runtime
Documentation=https://containerd.io
After=network.target
[Service]
ExecStartPre=/sbin/modprobe overlay
ExecStart=/bin/containerd
Restart=always
RestartSec=5
Delegate=yes
KillMode=process
OOMScoreAdjust=-999
LimitNOFILE=1048576
LimitNPROC=infinity
LimitCORE=infinity
[Install]
WantedBy=multi-user.target
EOF
### Configure the Kubelet
mv ${HOSTNAME}-key.pem ${HOSTNAME}.pem /var/lib/kubelet/
mv ${HOSTNAME}.kubeconfig /var/lib/kubelet/kubeconfig
mv ca.pem /var/lib/kubernetes/
# Create the kubelet-config.yaml configuration file
cat <<EOF | sudo tee /var/lib/kubelet/kubelet-config.yaml
kind: KubeletConfiguration
apiVersion: kubelet.config.k8s.io/v1beta1
authentication:
anonymous:
enabled: false
webhook:
enabled: true
x509:
clientCAFile: "/var/lib/kubernetes/ca.pem"
authorization:
mode: Webhook
clusterDomain: "cluster.local"
clusterDNS:
- "10.32.0.10"
podCIDR: "10.200.0.0/16"
resolvConf: "/run/systemd/resolve/resolv.conf"
runtimeRequestTimeout: "15m"
tlsCertFile: "/var/lib/kubelet/${HOSTNAME}.pem"
tlsPrivateKeyFile: "/var/lib/kubelet/${HOSTNAME}-key.pem"
EOF
# Create the kubelet.service systemd unit file:
cat <<EOF | sudo tee /etc/systemd/system/kubelet.service
[Unit]
Description=Kubernetes Kubelet
Documentation=https://github.com/kubernetes/kubernetes
After=containerd.service
Requires=containerd.service
[Service]
ExecStart=/usr/local/bin/kubelet \\
--config=/var/lib/kubelet/kubelet-config.yaml \\
--container-runtime=remote \\
--container-runtime-endpoint=unix:///var/run/containerd/containerd.sock \\
--image-pull-progress-deadline=2m \\
--kubeconfig=/var/lib/kubelet/kubeconfig \\
--network-plugin=cni \\
--register-node=true \\
--v=2
Restart=on-failure
RestartSec=5
[Install]
WantedBy=multi-user.target
EOF
### Configure the Kubernetes Proxy
mv kube-proxy.kubeconfig /var/lib/kube-proxy/kubeconfig
# Create the kube-proxy-config.yaml configuration file:
cat <<EOF | sudo tee /var/lib/kube-proxy/kube-proxy-config.yaml
kind: KubeProxyConfiguration
apiVersion: kubeproxy.config.k8s.io/v1alpha1
clientConnection:
kubeconfig: "/var/lib/kube-proxy/kubeconfig"
mode: "iptables"
clusterCIDR: "10.200.0.0/16"
EOF
# Create the kube-proxy.service systemd unit file:
cat <<EOF | sudo tee /etc/systemd/system/kube-proxy.service
[Unit]
Description=Kubernetes Kube Proxy
Documentation=https://github.com/kubernetes/kubernetes
[Service]
ExecStart=/usr/local/bin/kube-proxy \\
--config=/var/lib/kube-proxy/kube-proxy-config.yaml
Restart=on-failure
RestartSec=5
[Install]
WantedBy=multi-user.target
EOF
### Start the Worker Services
systemctl daemon-reload
systemctl enable containerd kubelet kube-proxy
systemctl restart containerd kubelet kube-proxy
##### Verification
Master Node 에서 Command 실행
"kubectl get nodes --kubeconfig admin.kubeconfig"
[root@master01 ~]# kubectl get node --kubeconfig admin.kubeconfig
NAME STATUS ROLES AGE VERSION
worker01 Ready <none> 2d1h v1.18.6
worker02 Ready <none> 2d1h v1.18.6
worker03 Ready <none> 2d1h v1.18.6
worker04 Ready <none> 5m7s v1.18.6