Binary installation Kubernetes (k8s) v1 23.4 ---

Posted by php new bie on Tue, 01 Mar 2022 04:47:50 +0100

1. Environment

Documents required in the document

reference resources: https://github.com/cby-chen/Kubernetes/releases/tag/cby

Host name

IP address

explain

Software

Master01

192.168.1.30

master node

kube-apiserver,kube-controller-manager,kube-scheduler,etcd,kubelet,kube-proxy,nfs-client

Master02

192.168.1.31

master node

kube-apiserver,kube-controller-manager,kube-scheduler,etcd,kubelet,kube-proxy,nfs-client

Master03

192.168.1.32

master node

kube-apiserver,kube-controller-manager,kube-scheduler,etcd,kubelet,kube-proxy,nfs-client

Node01

192.168.1.33

Node node

kubelet,kube-proxy,nfs-client

Node02

192.168.1.34

Node node

kubelet,kube-proxy,nfs-client

Node03

192.168.1.35

Node node

kubelet,kube-proxy,nfs-client

Node04

192.168.1.36

Node node

kubelet,kube-proxy,nfs-client

Node05

192.168.1.37

Node node

kubelet,kube-proxy,nfs-client

Lb01

192.168.1.38

Lb01 node

haproxy,keepalived

Lb02

192.168.1.39

Lb02 node

haproxy,keepalived

192.168.1.88

VIP

Software

edition

kernel

5.16.7-1.el8.elrepo.x86_64

CentOS 8

v8

kube-apiserver,kube-controller-manager,kube-scheduler,kubelet,kube-proxy

v1.23.4

etcd

v3.5.2

docker-ce

v20.10.9

containerd

v1.6.0

cfssl

v1.6.1

cni

v1.6.0

crictl

v1.23.0

haproxy

v1.8.27

keepalived

v2.1.5

Network segment

Physical host: 192.168.1.0/24

service: 10.96.0.0/12

pod: 172.16.0.0/12

If possible, it is recommended to install k8s cluster and etcd cluster separately

1.1.k8s basic system environment configuration

1.2. Configure IP

ssh root@192.168.1.76 "nmcli con mod ens18 ipv4.addresses 192.168.1.30/24; nmcli con mod ens18 ipv4.gateway 192.168.1.99; nmcli con mod ens18 ipv4.method manual; nmcli con mod ens18 ipv4.dns "8.8.8.8"; nmcli con up ens18"
ssh root@192.168.1.77 "nmcli con mod ens18 ipv4.addresses 192.168.1.31/24; nmcli con mod ens18 ipv4.gateway 192.168.1.99; nmcli con mod ens18 ipv4.method manual; nmcli con mod ens18 ipv4.dns "8.8.8.8"; nmcli con up ens18"
ssh root@192.168.1.78 "nmcli con mod ens18 ipv4.addresses 192.168.1.32/24; nmcli con mod ens18 ipv4.gateway 192.168.1.99; nmcli con mod ens18 ipv4.method manual; nmcli con mod ens18 ipv4.dns "8.8.8.8"; nmcli con up ens18"
ssh root@192.168.1.79 "nmcli con mod ens18 ipv4.addresses 192.168.1.33/24; nmcli con mod ens18 ipv4.gateway 192.168.1.99; nmcli con mod ens18 ipv4.method manual; nmcli con mod ens18 ipv4.dns "8.8.8.8"; nmcli con up ens18"
ssh root@192.168.1.80 "nmcli con mod ens18 ipv4.addresses 192.168.1.34/24; nmcli con mod ens18 ipv4.gateway 192.168.1.99; nmcli con mod ens18 ipv4.method manual; nmcli con mod ens18 ipv4.dns "8.8.8.8"; nmcli con up ens18"
ssh root@192.168.1.86 "nmcli con mod ens18 ipv4.addresses 192.168.1.35/24; nmcli con mod ens18 ipv4.gateway 192.168.1.99; nmcli con mod ens18 ipv4.method manual; nmcli con mod ens18 ipv4.dns "8.8.8.8"; nmcli con up ens18"
ssh root@192.168.1.87 "nmcli con mod ens18 ipv4.addresses 192.168.1.36/24; nmcli con mod ens18 ipv4.gateway 192.168.1.99; nmcli con mod ens18 ipv4.method manual; nmcli con mod ens18 ipv4.dns "8.8.8.8"; nmcli con up ens18"
ssh root@192.168.1.166 "nmcli con mod ens18 ipv4.addresses 192.168.1.37/24; nmcli con mod ens18 ipv4.gateway 192.168.1.99; nmcli con mod ens18 ipv4.method manual; nmcli con mod ens18 ipv4.dns "8.8.8.8"; nmcli con up ens18"
ssh root@192.168.1.100 "nmcli con mod ens18 ipv4.addresses 192.168.1.38/24; nmcli con mod ens18 ipv4.gateway 192.168.1.99; nmcli con mod ens18 ipv4.method manual; nmcli con mod ens18 ipv4.dns "8.8.8.8"; nmcli con up ens18"
ssh root@192.168.1.191 "nmcli con mod ens18 ipv4.addresses 192.168.1.39/24; nmcli con mod ens18 ipv4.gateway 192.168.1.99; nmcli con mod ens18 ipv4.method manual; nmcli con mod ens18 ipv4.dns "8.8.8.8"; nmcli con up ens18"

1.3. Set host name

hostnamectl set-hostname k8s-master01
hostnamectl set-hostname k8s-master02
hostnamectl set-hostname k8s-master03
hostnamectl set-hostname k8s-node01
hostnamectl set-hostname k8s-node02
hostnamectl set-hostname k8s-node03
hostnamectl set-hostname k8s-node04
hostnamectl set-hostname k8s-node05
hostnamectl set-hostname lb01
hostnamectl set-hostname lb02

1.4. Configure yum source

sudo sed -e 's|^mirrorlist=|#mirrorlist=|g' \
         -e 's|^#baseurl=http://mirror.centos.org/$contentdir|baseurl=http://192.168.1.123/centos|g' \
         -i.bak \
         /etc/yum.repos.d/CentOS-*.repo


sed -e 's|^mirrorlist=|#mirrorlist=|g' -e 's|^#baseurl=http://mirror.centos.org/\$contentdir|baseurl=http://192.168.1.123/centos|g' -i.bak  /etc/yum.repos.d/CentOS-*.repo

1.5. Install some necessary tools

yum -y install wget jq psmisc vim net-tools  telnet yum-utils device-mapper-persistent-data lvm2 git network-scripts tar curl -y

1.6. Install docker tool

curl -fsSL https://get.docker.com | bash -s docker --mirror Aliyun

1.7. Turn off the firewall

systemctl disable --now firewalld

1.8. Close SELinux

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

1.9. Close swap partition

sed -ri 's/.*swap.*/#&/' /etc/fstab
swapoff -a && sysctl -w vm.swappiness=0
cat /etc/fstab

# /dev/mapper/centos-swap swap                    swap    defaults        0 0

1.10. Close NetworkManager and enable network

systemctl disable --now NetworkManager
systemctl start network && systemctl enable network

1.11. Time synchronization

Server

yum install chrony -y
cat > /etc/chrony.conf << EOF 
pool ntp.aliyun.com iburst
driftfile /var/lib/chrony/drift
makestep 1.0 3
rtcsync
allow 192.168.1.0/24
local stratum 10
keyfile /etc/chrony.keys
leapsectz right/UTC
logdir /var/log/chrony
EOF

systemctl restart chronyd
systemctl enable chronyd

client

yum install chrony -y
vim /etc/chrony.conf
cat /etc/chrony.conf | grep -v  "^#" | grep -v "^$"
pool 192.168.1.30 iburst
driftfile /var/lib/chrony/drift
makestep 1.0 3
rtcsync
keyfile /etc/chrony.keys
leapsectz right/UTC
logdir /var/log/chrony

systemctl restart chronyd ; systemctl enable chronyd


yum install chrony -y ; sed -i "s#2.centos.pool.ntp.org#192.168.1.30#g" /etc/chrony.conf ; systemctl restart chronyd ; systemctl enable chronyd


Use client for authentication

chronyc sources -v

1.12. Configure ulimit

ulimit -SHn 65535
cat >> /etc/security/limits.conf <<EOF
* soft nofile 655360
* hard nofile 131072
* soft nproc 655350
* hard nproc 655350
* seft memlock unlimited
* hard memlock unlimitedd
EOF

1.13. Configure password free login

yum install -y sshpass
ssh-keygen -f /root/.ssh/id_rsa -P ''
export IP="192.168.1.30 192.168.1.31 192.168.1.32 192.168.1.33 192.168.1.34 192.168.1.35 192.168.1.36 192.168.1.37 192.168.1.38 192.168.1.39"
export SSHPASS=123123
for HOST in $IP;do
     sshpass -e ssh-copy-id -o StrictHostKeyChecking=no $HOST
done

1.14. Add enable source

by RHEL-8 or CentOS-8 Configuration source
yum install https://www.elrepo.org/elrepo-release-8.el8.elrepo.noarch.rpm

by RHEL-7 SL-7 or CentOS-7 install ELRepo 
yum install https://www.elrepo.org/elrepo-release-7.el7.elrepo.noarch.rpm

View available installation packages
yum  --disablerepo="*"  --enablerepo="elrepo-kernel"  list  available

1.15. Upgrade kernel to above version 4.18

Install the latest kernel
# I choose the stable version of kernel ml here. If you need to update the long-term maintenance version of kernel LT  
yum  --enablerepo=elrepo-kernel  install  kernel-ml

View which kernels are installed
rpm -qa | grep kernel
kernel-core-4.18.0-358.el8.x86_64
kernel-tools-4.18.0-358.el8.x86_64
kernel-ml-core-5.16.7-1.el8.elrepo.x86_64
kernel-ml-5.16.7-1.el8.elrepo.x86_64
kernel-modules-4.18.0-358.el8.x86_64
kernel-4.18.0-358.el8.x86_64
kernel-tools-libs-4.18.0-358.el8.x86_64
kernel-ml-modules-5.16.7-1.el8.elrepo.x86_64


View default kernel
grubby --default-kernel
/boot/vmlinuz-5.16.7-1.el8.elrepo.x86_64


If not, use the latest command settings
grubby --set-default /boot/vmlinuz-「Your kernel version」.x86_64

Restart effective
reboot

The integration command is:
yum install https://www.elrepo.org/elrepo-release-8.el8.elrepo.noarch.rpm -y ; yum  --disablerepo="*"  --enablerepo="elrepo-kernel"  list  available -y ; yum  --enablerepo=elrepo-kernel  install  kernel-ml -y ; grubby --default-kernel ; reboot

1.16. Install ipvsadm

yum install ipvsadm ipset sysstat conntrack libseccomp -y

cat >> /etc/modules-load.d/ipvs.conf <<EOF
cat 
ip_vs
ip_vs_rr
ip_vs_wrr
ip_vs_sh
nf_conntrack
ip_tables
ip_set
xt_set
ipt_set
ipt_rpfilter
ipt_REJECT
ipip
EOF

systemctl restart systemd-modules-load.service

lsmod | grep -e ip_vs -e nf_conntrack
ip_vs_sh               16384  0
ip_vs_wrr              16384  0
ip_vs_rr               16384  0
ip_vs                 180224  6 ip_vs_rr,ip_vs_sh,ip_vs_wrr
nf_conntrack          176128  1 ip_vs
nf_defrag_ipv6         24576  2 nf_conntrack,ip_vs
nf_defrag_ipv4         16384  1 nf_conntrack
libcrc32c              16384  3 nf_conntrack,xfs,ip_vs

1.17. Modify kernel parameters

cat <<EOF > /etc/sysctl.d/k8s.conf
net.ipv4.ip_forward = 1
net.bridge.bridge-nf-call-iptables = 1
fs.may_detach_mounts = 1
vm.overcommit_memory=1
vm.panic_on_oom=0
fs.inotify.max_user_watches=89100
fs.file-max=52706963
fs.nr_open=52706963
net.netfilter.nf_conntrack_max=2310720


net.ipv4.tcp_keepalive_time = 600
net.ipv4.tcp_keepalive_probes = 3
net.ipv4.tcp_keepalive_intvl =15
net.ipv4.tcp_max_tw_buckets = 36000
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_max_orphans = 327680
net.ipv4.tcp_orphan_retries = 3
net.ipv4.tcp_syncookies = 1
net.ipv4.tcp_max_syn_backlog = 16384
net.ipv4.ip_conntrack_max = 65536
net.ipv4.tcp_max_syn_backlog = 16384
net.ipv4.tcp_timestamps = 0
net.core.somaxconn = 16384
EOF

sysctl --system

1.18. Configure hosts local resolution for all nodes

cat > /etc/hosts <<EOF
127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.1.30 k8s-master01
192.168.1.31 k8s-master02
192.168.1.32 k8s-master03
192.168.1.33 k8s-node01
192.168.1.34 k8s-node02
192.168.1.35 k8s-node03
192.168.1.36 k8s-node04
192.168.1.37 k8s-node05
192.168.1.38 lb01
192.168.1.38 lb02
192.168.1.88 lb-vip
EOF

2.k8s basic component installation

2.1. Install container as Runtime on all k8s nodes

yum install containerd -y

2.1.1 modules required for configuring container

cat <<EOF | sudo tee /etc/modules-load.d/containerd.conf
overlay
br_netfilter
EOF

2.1.2 loading module

systemctl restart systemd-modules-load.service

2.1.3 kernel required for configuring container

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
EOF

# Load kernel

sysctl --system

2.1.4 create the configuration file of container

mkdir -p /etc/containerd
containerd config default | tee /etc/containerd/config.toml


modify Containerd Configuration file for
sed -i '/containerd\.runtimes\.runc\.options/ a\\t\tSystemdCgroup\ =\ true' /etc/containerd/config.toml

cat /etc/containerd/config.toml

# Find containerd runtimes. runc. Options, add systemdcgroup under it = true

[plugins."io.containerd.grpc.v1.cri".containerd.runtimes.runc.options]
              SystemdCgroup = true
    [plugins."io.containerd.grpc.v1.cri".cni]


# Add sandbox_image default address changed to match version address

    sandbox_image = "registry.cn-hangzhou.aliyuncs.com/google_containers/pause:3.6"

2.1.5 start and set to start

systemctl daemon-reload
systemctl enable --now

2.1.6 configure the runtime location of crictl client connection

cat > /etc/crictl.yaml <<EOF
runtime-endpoint: unix:///run/containerd/containerd.sock
image-endpoint: unix:///run/containerd/containerd.sock
timeout: 10
debug: false
EOF

2.2.k8s and etcd download and installation (only in master01)

2.2.1 download k8s installation package (which one you use)

1.download kubernetes1.23.+Binary package for
github Binary package download address: https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG/CHANGELOG-1.23.md

wget https://dl.k8s.io/v1.23.4/kubernetes-server-linux-amd64.tar.gz

2.download etcdctl Binary package
github Binary package download address: https://github.com/etcd-io/etcd/releases

wget https://github.com/etcd-io/etcd/releases/download/v3.5.2/etcd-v3.5.2-linux-amd64.tar.gz

3.docker-ce Binary package download address
 Binary package download address: https://download.docker.com/linux/static/stable/x86_64/

Here you need to download 20.10.+edition

wget https://download.docker.com/linux/static/stable/x86_64/docker-20.10.9.tgz

4.containerd Binary package download
github Download address: https://github.com/containerd/containerd/releases

containerd Download tape when downloading cni Binary package of the plug-in.

wget https://github.com/containerd/containerd/releases/download/v1.6.0-rc.2/cri-containerd-cni-1.6.0-rc.2-linux-amd64.tar.gz

5.download cfssl Binary package
github Binary package download address: https://github.com/cloudflare/cfssl/releases

wget https://github.com/cloudflare/cfssl/releases/download/v1.6.1/cfssl_1.6.1_linux_amd64
wget https://github.com/cloudflare/cfssl/releases/download/v1.6.1/cfssljson_1.6.1_linux_amd64
wget https://github.com/cloudflare/cfssl/releases/download/v1.6.1/cfssl-certinfo_1.6.1_linux_amd64

6.cni Plug in download
github Download address: https://github.com/containernetworking/plugins/releases

wget https://github.com/containernetworking/plugins/releases/download/v1.0.1/cni-plugins-linux-amd64-v1.0.1.tgz

7.crictl Client binary Download
github Download: https://github.com/kubernetes-sigs/cri-tools/releases

wget https://github.com/kubernetes-sigs/cri-tools/releases/download/v1.23.0/crictl-v1.23.0-linux-amd64.tar.gz




decompression k8s install files
tar -xf kubernetes-server-linux-amd64.tar.gz  --strip-components=3 -C /usr/local/bin kubernetes/server/bin/kube{let,ctl,-apiserver,-controller-manager,-scheduler,-proxy}

decompression etcd install files
tar -xf etcd-v3.5.2-linux-amd64.tar.gz --strip-components=1 -C /usr/local/bin etcd-v3.5.2-linux-amd64/etcd{,ctl}

# View the contents under / usr/local/bin

ls /usr/local/bin/
etcd  etcdctl  kube-apiserver  kube-controller-manager  kubectl  kubelet  kube-proxy  kube-scheduler

2.2.2 view version

[root@k8s-master01 ~]# kubelet --version
Kubernetes v1.23.4
[root@k8s-master01 ~]# etcdctl version
etcdctl version: 3.5.1
API version: 3.5

2.2.3 sending components to other k8s nodes

Master='k8s-master02 k8s-master03'
Work='k8s-node01 k8s-node02 k8s-node03 k8s-node04 k8s-node05'
for NODE in $Master; do echo $NODE; scp /usr/local/bin/kube{let,ctl,-apiserver,-controller-manager,-scheduler,-proxy} $NODE:/usr/local/bin/; scp /usr/local/bin/etcd* $NODE:/usr/local/bin/; done
for NODE in $Work; do     scp /usr/local/bin/kube{let,-proxy} $NODE:/usr/local/bin/ ; done

2.2.4 documents related to cloning certificate

git clone https://github.com/cby-chen/Kubernetes.git

2.2.5 create directories for all k8s nodes

mkdir -p /opt/cni/bin

3. Generation of relevant certificates

master01 Node download certificate generation tool
wget "https://github.com/cloudflare/cfssl/releases/download/v1.6.1/cfssl_1.6.1_linux_amd64" -O /usr/local/bin/cfssl
wget "https://github.com/cloudflare/cfssl/releases/download/v1.6.1/cfssljson_1.6.1_linux_amd64" -O /usr/local/bin/cfssljson
chmod +x /usr/local/bin/cfssl /usr/local/bin/cfssljson

3.1. Generate etcd certificate

Unless otherwise specified, the following operations are performed on all master nodes

3.1.1 create a certificate storage directory for all master nodes

mkdir /etc/etcd/ssl -p

3.1.2master01 node generates etcd certificate

cd Kubernetes/pki/

# Generate etcd certificate and etcd certificate key (if you think it may be expanded in the future, you can write more in the ip and reserve them)

cfssl gencert -initca etcd-ca-csr.json | cfssljson -bare /etc/etcd/ssl/etcd-ca

cfssl gencert \
   -ca=/etc/etcd/ssl/etcd-ca.pem \
   -ca-key=/etc/etcd/ssl/etcd-ca-key.pem \
   -config=ca-config.json \
   -hostname=127.0.0.1,k8s-master01,k8s-master02,k8s-master03,192.168.1.30,192.168.1.31,192.168.1.32 \
   -profile=kubernetes \
   etcd-csr.json | cfssljson -bare /etc/etcd/ssl/etcd

3.1.3 copy certificates to other nodes

Master='k8s-master02 k8s-master03'
for NODE in $Master; do
     ssh $NODE "mkdir -p /etc/etcd/ssl"
     for FILE in etcd-ca-key.pem  etcd-ca.pem  etcd-key.pem  etcd.pem; do
       scp /etc/etcd/ssl/${FILE} $NODE:/etc/etcd/ssl/${FILE}
     done
 done

3.2. Generate k8s relevant certificates

Unless otherwise specified, the following operations are performed on all master nodes

3.2.1 create certificate storage directory for all k8s nodes

mkdir -p /etc/kubernetes/pki

3.2.2master 01 node generates k8s certificate

# Generate a root certificate

cfssl gencert -initca ca-csr.json | cfssljson -bare /etc/kubernetes/pki/ca

# 10.96.0.1 is the first address of the service network segment, which needs to be calculated. 192.168.1.88 is the highly available vip address

cfssl gencert   \
-ca=/etc/kubernetes/pki/ca.pem   \
-ca-key=/etc/kubernetes/pki/ca-key.pem   \
-config=ca-config.json   \
-hostname=10.96.0.1,192.168.1.88,127.0.0.1,kubernetes,kubernetes.default,kubernetes.default.svc,kubernetes.default.svc.cluster,kubernetes.default.svc.cluster.local,x.oiox.cn,k.oiox.cn,l.oiox.cn,o.oiox.cn,192.168.1.30,192.168.1.31,192.168.1.32,192.168.1.33,192.168.1.34,192.168.1.35,192.168.1.36,192.168.1.37,192.168.1.38,192.168.1.39,192.168.1.40,192.168.1.41   \
-profile=kubernetes   apiserver-csr.json | cfssljson -bare /etc/kubernetes/pki/apiserver

3.2.3 generate apiserver aggregation certificate

cfssl gencert   -initca front-proxy-ca-csr.json | cfssljson -bare /etc/kubernetes/pki/front-proxy-ca 

# There is a warning that can be ignored

cfssl gencert   -ca=/etc/kubernetes/pki/front-proxy-ca.pem   -ca-key=/etc/kubernetes/pki/front-proxy-ca-key.pem   -config=ca-config.json   -profile=kubernetes   front-proxy-client-csr.json | cfssljson -bare /etc/kubernetes/pki/front-proxy-client

3.2.4 generate controller manage certificate

cfssl gencert \
   -ca=/etc/kubernetes/pki/ca.pem \
   -ca-key=/etc/kubernetes/pki/ca-key.pem \
   -config=ca-config.json \
   -profile=kubernetes \
   manager-csr.json | cfssljson -bare /etc/kubernetes/pki/controller-manager

# Set a cluster entry

kubectl config set-cluster kubernetes \
     --certificate-authority=/etc/kubernetes/pki/ca.pem \
     --embed-certs=true \
     --server=https://192.168.1.88:8443 \
     --kubeconfig=/etc/kubernetes/controller-manager.kubeconfig

# Set an environment item and a context

kubectl config set-context system:kube-controller-manager@kubernetes \
    --cluster=kubernetes \
    --user=system:kube-controller-manager \
    --kubeconfig=/etc/kubernetes/controller-manager.kubeconfig

# Set a user item

kubectl config set-credentials system:kube-controller-manager \
     --client-certificate=/etc/kubernetes/pki/controller-manager.pem \
     --client-key=/etc/kubernetes/pki/controller-manager-key.pem \
     --embed-certs=true \
     --kubeconfig=/etc/kubernetes/controller-manager.kubeconfig

# Set default environment

kubectl config use-context system:kube-controller-manager@kubernetes \
     --kubeconfig=/etc/kubernetes/controller-manager.kubeconfig

cfssl gencert \
   -ca=/etc/kubernetes/pki/ca.pem \
   -ca-key=/etc/kubernetes/pki/ca-key.pem \
   -config=ca-config.json \
   -profile=kubernetes \
   scheduler-csr.json | cfssljson -bare /etc/kubernetes/pki/scheduler

kubectl config set-cluster kubernetes \
     --certificate-authority=/etc/kubernetes/pki/ca.pem \
     --embed-certs=true \
     --server=https://192.168.1.88:8443 \
     --kubeconfig=/etc/kubernetes/scheduler.kubeconfig

kubectl config set-credentials system:kube-scheduler \
     --client-certificate=/etc/kubernetes/pki/scheduler.pem \
     --client-key=/etc/kubernetes/pki/scheduler-key.pem \
     --embed-certs=true \
     --kubeconfig=/etc/kubernetes/scheduler.kubeconfig

kubectl config set-context system:kube-scheduler@kubernetes \
     --cluster=kubernetes \
     --user=system:kube-scheduler \
     --kubeconfig=/etc/kubernetes/scheduler.kubeconfig

kubectl config use-context system:kube-scheduler@kubernetes \
     --kubeconfig=/etc/kubernetes/scheduler.kubeconfig

cfssl gencert \
   -ca=/etc/kubernetes/pki/ca.pem \
   -ca-key=/etc/kubernetes/pki/ca-key.pem \
   -config=ca-config.json \
   -profile=kubernetes \
   admin-csr.json | cfssljson -bare /etc/kubernetes/pki/admin

kubectl config set-cluster kubernetes     --certificate-authority=/etc/kubernetes/pki/ca.pem     --embed-certs=true     --server=https://192.168.1.88:8443     --kubeconfig=/etc/kubernetes/admin.kubeconfig

kubectl config set-credentials kubernetes-admin     --client-certificate=/etc/kubernetes/pki/admin.pem     --client-key=/etc/kubernetes/pki/admin-key.pem     --embed-certs=true     --kubeconfig=/etc/kubernetes/admin.kubeconfig

kubectl config set-context kubernetes-admin@kubernetes     --cluster=kubernetes     --user=kubernetes-admin     --kubeconfig=/etc/kubernetes/admin.kubeconfig

kubectl config use-context kubernetes-admin@kubernetes     --kubeconfig=/etc/kubernetes/admin.kubeconfig

3.2.5 create ServiceAccount Key - secret

openssl genrsa -out /etc/kubernetes/pki/sa.key 2048
openssl rsa -in /etc/kubernetes/pki/sa.key -pubout -out /etc/kubernetes/pki/sa.pub

3.2.6 send certificates to other master nodes

for NODE in k8s-master02 k8s-master03; do 
for FILE in $(ls /etc/kubernetes/pki | grep -v etcd); do 
scp /etc/kubernetes/pki/${FILE} $NODE:/etc/kubernetes/pki/${FILE};
done; 
for FILE in admin.kubeconfig controller-manager.kubeconfig scheduler.kubeconfig; do 
scp /etc/kubernetes/${FILE} $NODE:/etc/kubernetes/${FILE};
done;
done

3.2.7 viewing certificates

ls /etc/kubernetes/pki/
admin.csr      apiserver-key.pem  ca.pem                      front-proxy-ca.csr      front-proxy-client-key.pem  scheduler.csr
admin-key.pem  apiserver.pem      controller-manager.csr      front-proxy-ca-key.pem  front-proxy-client.pem      scheduler-key.pem
admin.pem      ca.csr             controller-manager-key.pem  front-proxy-ca.pem      sa.key                      scheduler.pem
apiserver.csr  ca-key.pem         controller-manager.pem      front-proxy-client.csr  sa.pub

# A total of 23 is right

ls /etc/kubernetes/pki/ |wc -l
23

4.k8s system component configuration

4.1.etcd configuration

4.1.1master01 configuration

cat > /etc/etcd/etcd.config.yml << EOF 
name: 'k8s-master01'
data-dir: /var/lib/etcd
wal-dir: /var/lib/etcd/wal
snapshot-count: 5000
heartbeat-interval: 100
election-timeout: 1000
quota-backend-bytes: 0
listen-peer-urls: 'https://192.168.1.30:2380'
listen-client-urls: 'https://192.168.1.30:2379,http://127.0.0.1:2379'
max-snapshots: 3
max-wals: 5
cors:
initial-advertise-peer-urls: 'https://192.168.1.30:2380'
advertise-client-urls: 'https://192.168.1.30:2379'
discovery:
discovery-fallback: 'proxy'
discovery-proxy:
discovery-srv:
initial-cluster: 'k8s-master01=https://192.168.1.30:2380,k8s-master02=https://192.168.1.31:2380,k8s-master03=https://192.168.1.32:2380'
initial-cluster-token: 'etcd-k8s-cluster'
initial-cluster-state: 'new'
strict-reconfig-check: false
enable-v2: true
enable-pprof: true
proxy: 'off'
proxy-failure-wait: 5000
proxy-refresh-interval: 30000
proxy-dial-timeout: 1000
proxy-write-timeout: 5000
proxy-read-timeout: 0
client-transport-security:
  cert-file: '/etc/kubernetes/pki/etcd/etcd.pem'
  key-file: '/etc/kubernetes/pki/etcd/etcd-key.pem'
  client-cert-auth: true
  trusted-ca-file: '/etc/kubernetes/pki/etcd/etcd-ca.pem'
  auto-tls: true
peer-transport-security:
  cert-file: '/etc/kubernetes/pki/etcd/etcd.pem'
  key-file: '/etc/kubernetes/pki/etcd/etcd-key.pem'
  peer-client-cert-auth: true
  trusted-ca-file: '/etc/kubernetes/pki/etcd/etcd-ca.pem'
  auto-tls: true
debug: false
log-package-levels:
log-outputs: [default]
force-new-cluster: false
EOF

4.1.2master02 configuration

cat > /etc/etcd/etcd.config.yml << EOF 
name: 'k8s-master02'
data-dir: /var/lib/etcd
wal-dir: /var/lib/etcd/wal
snapshot-count: 5000
heartbeat-interval: 100
election-timeout: 1000
quota-backend-bytes: 0
listen-peer-urls: 'https://192.168.1.31:2380'
listen-client-urls: 'https://192.168.1.31:2379,http://127.0.0.1:2379'
max-snapshots: 3
max-wals: 5
cors:
initial-advertise-peer-urls: 'https://192.168.1.31:2380'
advertise-client-urls: 'https://192.168.1.31:2379'
discovery:
discovery-fallback: 'proxy'
discovery-proxy:
discovery-srv:
initial-cluster: 'k8s-master01=https://192.168.1.30:2380,k8s-master02=https://192.168.1.31:2380,k8s-master03=https://192.168.1.32:2380'
initial-cluster-token: 'etcd-k8s-cluster'
initial-cluster-state: 'new'
strict-reconfig-check: false
enable-v2: true
enable-pprof: true
proxy: 'off'
proxy-failure-wait: 5000
proxy-refresh-interval: 30000
proxy-dial-timeout: 1000
proxy-write-timeout: 5000
proxy-read-timeout: 0
client-transport-security:
  cert-file: '/etc/kubernetes/pki/etcd/etcd.pem'
  key-file: '/etc/kubernetes/pki/etcd/etcd-key.pem'
  client-cert-auth: true
  trusted-ca-file: '/etc/kubernetes/pki/etcd/etcd-ca.pem'
  auto-tls: true
peer-transport-security:
  cert-file: '/etc/kubernetes/pki/etcd/etcd.pem'
  key-file: '/etc/kubernetes/pki/etcd/etcd-key.pem'
  peer-client-cert-auth: true
  trusted-ca-file: '/etc/kubernetes/pki/etcd/etcd-ca.pem'
  auto-tls: true
debug: false
log-package-levels:
log-outputs: [default]
force-new-cluster: false
EOF

4.1.3 master03 configuration

cat > /etc/etcd/etcd.config.yml << EOF 
name: 'k8s-master03'
data-dir: /var/lib/etcd
wal-dir: /var/lib/etcd/wal
snapshot-count: 5000
heartbeat-interval: 100
election-timeout: 1000
quota-backend-bytes: 0
listen-peer-urls: 'https://192.168.1.32:2380'
listen-client-urls: 'https://192.168.1.32:2379,http://127.0.0.1:2379'
max-snapshots: 3
max-wals: 5
cors:
initial-advertise-peer-urls: 'https://192.168.1.32:2380'
advertise-client-urls: 'https://192.168.1.32:2379'
discovery:
discovery-fallback: 'proxy'
discovery-proxy:
discovery-srv:
initial-cluster: 'k8s-master01=https://192.168.1.30:2380,k8s-master02=https://192.168.1.31:2380,k8s-master03=https://192.168.1.32:2380'
initial-cluster-token: 'etcd-k8s-cluster'
initial-cluster-state: 'new'
strict-reconfig-check: false
enable-v2: true
enable-pprof: true
proxy: 'off'
proxy-failure-wait: 5000
proxy-refresh-interval: 30000
proxy-dial-timeout: 1000
proxy-write-timeout: 5000
proxy-read-timeout: 0
client-transport-security:
  cert-file: '/etc/kubernetes/pki/etcd/etcd.pem'
  key-file: '/etc/kubernetes/pki/etcd/etcd-key.pem'
  client-cert-auth: true
  trusted-ca-file: '/etc/kubernetes/pki/etcd/etcd-ca.pem'
  auto-tls: true
peer-transport-security:
  cert-file: '/etc/kubernetes/pki/etcd/etcd.pem'
  key-file: '/etc/kubernetes/pki/etcd/etcd-key.pem'
  peer-client-cert-auth: true
  trusted-ca-file: '/etc/kubernetes/pki/etcd/etcd-ca.pem'
  auto-tls: true
debug: false
log-package-levels:
log-outputs: [default]
force-new-cluster: false
EOF

4.2. Create service (all master node operations)

4.2.1 create etcd Service and start

cat > /usr/lib/systemd/system/etcd.service << EOF

[Unit]
Description=Etcd Service
Documentation=https://coreos.com/etcd/docs/latest/
After=network.target

[Service]
Type=notify
ExecStart=/usr/local/bin/etcd --config-file=/etc/etcd/etcd.config.yml
Restart=on-failure
RestartSec=10
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target
Alias=etcd3.service

EOF

4.2.2 create etcd certificate directory

mkdir /etc/kubernetes/pki/etcd
ln -s /etc/etcd/ssl/* /etc/kubernetes/pki/etcd/
systemctl daemon-reload
systemctl enable --now etcd

4.2.3 viewing etcd status

export ETCDCTL_API=3
etcdctl --endpoints="192.168.1.32:2379,192.168.1.31:2379,192.168.1.30:2379" --cacert=/etc/kubernetes/pki/etcd/etcd-ca.pem --cert=/etc/kubernetes/pki/etcd/etcd.pem --key=/etc/kubernetes/pki/etcd/etcd-key.pem  endpoint status --write-out=table
+-------------------+------------------+---------+---------+-----------+------------+-----------+------------+--------------------+--------+
|     ENDPOINT      |        ID        | VERSION | DB SIZE | IS LEADER | IS LEARNER | RAFT TERM | RAFT INDEX | RAFT APPLIED INDEX | ERRORS |
+-------------------+------------------+---------+---------+-----------+------------+-----------+------------+--------------------+--------+
| 192.168.1.32:2379 | 56875ab4a12c94e8 |   3.5.1 |   25 kB |     false |      false |         2 |          8 |                  8 |        |
| 192.168.1.31:2379 | 33df6a8fe708d3fd |   3.5.1 |   25 kB |      true |      false |         2 |          8 |                  8 |        |
| 192.168.1.30:2379 | 58fbe5ec9743048f |   3.5.1 |   20 kB |     false |      false |         2 |          8 |                  8 |        |
+-------------------+------------------+---------+---------+-----------+------------+-----------+------------+--------------------+--------+

5. High availability configuration

5.1 operate on lb01 and lb02 servers

5.1.1 install keepalived and haproxy services

systemctl disable --now firewalld

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


yum -y install keepalived haproxy

5.1.2 modify haproxy configuration file (two configuration files are the same)

# cp /etc/haproxy/haproxy.cfg /etc/haproxy/haproxy.cfg.bak

cat >/etc/haproxy/haproxy.cfg<<"EOF"
global
 maxconn 2000
 ulimit-n 16384
 log 127.0.0.1 local0 err
 stats timeout 30s

defaults
 log global
 mode http
 option httplog
 timeout connect 5000
 timeout client 50000
 timeout server 50000
 timeout http-request 15s
 timeout http-keep-alive 15s


frontend monitor-in
 bind *:33305
 mode http
 option httplog
 monitor-uri /monitor

frontend k8s-master
 bind 0.0.0.0:8443
 bind 127.0.0.1:8443
 mode tcp
 option tcplog
 tcp-request inspect-delay 5s
 default_backend k8s-master


backend k8s-master
 mode tcp
 option tcplog
 option tcp-check
 balance roundrobin
 default-server inter 10s downinter 5s rise 2 fall 2 slowstart 60s maxconn 250 maxqueue 256 weight 100
 server  k8s-master01  192.168.1.30:6443 check
 server  k8s-master02  192.168.1.31:6443 check
 server  k8s-master03  192.168.1.32:6443 check
EOF

5.1.3lb01 configure the kept master node

#cp /etc/keepalived/keepalived.conf /etc/keepalived/keepalived.conf.bak

cat > /etc/keepalived/keepalived.conf << EOF
! Configuration File for keepalived

global_defs {
    router_id LVS_DEVEL
}
vrrp_script chk_apiserver {
    script "/etc/keepalived/check_apiserver.sh"
    interval 5 
    weight -5
    fall 2
    rise 1
}
vrrp_instance VI_1 {
    state MASTER
    interface ens18
    mcast_src_ip 192.168.1.38
    virtual_router_id 51
    priority 100
    nopreempt
    advert_int 2
    authentication {
        auth_type PASS
        auth_pass K8SHA_KA_AUTH
    }
    virtual_ipaddress {
        192.168.1.88
    }
    track_script {
      chk_apiserver 
} }

EOF

5.1.4lb02 configure the kept backup node

# cp /etc/keepalived/keepalived.conf /etc/keepalived/keepalived.conf.bak

cat > /etc/keepalived/keepalived.conf << EOF
! Configuration File for keepalived

global_defs {
    router_id LVS_DEVEL
}
vrrp_script chk_apiserver {
    script "/etc/keepalived/check_apiserver.sh"
    interval 5 
    weight -5
    fall 2
    rise 1

}
vrrp_instance VI_1 {
    state BACKUP
    interface ens18
    mcast_src_ip 192.168.1.39
    virtual_router_id 51
    priority 50
    nopreempt
    advert_int 2
    authentication {
        auth_type PASS
        auth_pass K8SHA_KA_AUTH
    }
    virtual_ipaddress {
        192.168.1.88
    }
    track_script {
      chk_apiserver 
} }

EOF

5.1.5 health check script configuration (two lb hosts)

cat >  /etc/keepalived/check_apiserver.sh << EOF
#!/bin/bash

err=0
for k in \$(seq 1 3)
do
    check_code=\$(pgrep haproxy)
    if [[ \$check_code == "" ]]; then
        err=\$(expr \$err + 1)
        sleep 1
        continue
    else
        err=0
        break
    fi
done

if [[ \$err != "0" ]]; then
    echo "systemctl stop keepalived"
    /usr/bin/systemctl stop keepalived
    exit 1
else
    exit 0
fi
EOF

# Authorize scripts

chmod +x /etc/keepalived/check_apiserver.sh

5.1.6 start service

systemctl daemon-reload
systemctl enable --now haproxy
systemctl enable --now keepalived

5.1.7 test high availability

# Can ping the same

[root@k8s-node02 ~]# ping 192.168.1.88

# telnet access

[root@k8s-node02 ~]# telnet 192.168.1.88 8443

# Close the primary node to see if the vip drifts to the standby node

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