kubeadm-highavailiability (English / 中文) - kubernetes high availiability deployment based on kubeadm, for Kubernetes version v1.11.x/v1.9.x/v1.7.x/v1.6.x
- 中文文档(for v1.11.x版本)
- English document(for v1.11.x version)
- 中文文档(for v1.9.x版本)
- English document(for v1.9.x version)
- 中文文档(for v1.7.x版本)
- English document(for v1.7.x version)
- 中文文档(for v1.6.x版本)
- English document(for v1.6.x version)
- This operation instruction is for version v1.11.x kubernetes cluster
v1.11.x version now support deploy tls etcd cluster in control plane
- deployment architecture
- prerequisites
- kubernetes installation
- masters high availiability installation
- masters load balance settings
- workers join kubernetes cluster
- verify kubernetes cluster installation
- kubernetes components:
kube-apiserver: exposes the Kubernetes API. It is the front-end for the Kubernetes control plane. It is designed to scale horizontally – that is, it scales by deploying more instances.
etcd: is used as Kubernetes’ backing store. All cluster data is stored here. Always have a backup plan for etcd’s data for your Kubernetes cluster.
kube-scheduler: watches newly created pods that have no node assigned, and selects a node for them to run on.
kube-controller-manager: runs controllers, which are the background threads that handle routine tasks in the cluster. Logically, each controller is a separate process, but to reduce complexity, they are all compiled into a single binary and run in a single process.
kubelet: is the primary node agent. It watches for pods that have been assigned to its node (either by apiserver or via local configuration file)
kube-proxy: enables the Kubernetes service abstraction by maintaining network rules on the host and performing connection forwarding.
- load balancer
keepalived cluster config a virtual IP address (192.168.20.10), this virtual IP address point to k8s-master01, k8s-master02, k8s-master03.
nginx service as the load balancer of k8s-master01, k8s-master02, k8s-master03's apiserver. The other nodes kubernetes services connect the keepalived virtual ip address (192.168.20.10) and nginx exposed port (16443) to communicate with the master cluster's apiservers.
HostName | IPAddress | Notes | Components |
---|---|---|---|
k8s-master01 ~ 03 | 192.168.20.20 ~ 22 | master nodes * 3 | keepalived, nginx, etcd, kubelet, kube-apiserver |
k8s-master-lb | 192.168.20.10 | keepalived virtual IP | N/A |
k8s-node01 ~ 08 | 192.168.20.30 ~ 37 | worker nodes * 8 | kubelet |
-
Linux version: CentOS 7.4.1708
-
Core version: 4.6.4-1.el7.elrepo.x86_64
$ cat /etc/redhat-release
CentOS Linux release 7.4.1708 (Core)
$ uname -r
4.6.4-1.el7.elrepo.x86_64
- docker version: 17.12.0-ce-rc2
$ docker version
Client:
Version: 17.12.0-ce-rc2
API version: 1.35
Go version: go1.9.2
Git commit: f9cde63
Built: Tue Dec 12 06:42:20 2017
OS/Arch: linux/amd64
Server:
Engine:
Version: 17.12.0-ce-rc2
API version: 1.35 (minimum version 1.12)
Go version: go1.9.2
Git commit: f9cde63
Built: Tue Dec 12 06:44:50 2017
OS/Arch: linux/amd64
Experimental: false
- kubeadm version: v1.11.1
$ kubeadm version
kubeadm version: &version.Info{Major:"1", Minor:"11", GitVersion:"v1.11.1", GitCommit:"b1b29978270dc22fecc592ac55d903350454310a", GitTreeState:"clean", BuildDate:"2018-07-17T18:50:16Z", GoVersion:"go1.10.3", Compiler:"gc", Platform:"linux/amd64"}
- kubelet version: v1.11.1
$ kubelet --version
Kubernetes v1.11.1
- networks addons
calico
- required docker images and tags
# kuberentes basic components
# use kubeadm to list all required docker images
$ kubeadm config images list --kubernetes-version=v1.11.1
k8s.gcr.io/kube-apiserver-amd64:v1.11.1
k8s.gcr.io/kube-controller-manager-amd64:v1.11.1
k8s.gcr.io/kube-scheduler-amd64:v1.11.1
k8s.gcr.io/kube-proxy-amd64:v1.11.1
k8s.gcr.io/pause:3.1
k8s.gcr.io/etcd-amd64:3.2.18
k8s.gcr.io/coredns:1.1.3
# use kubeadm to pull all required docker images
$ kubeadm config images pull --kubernetes-version=v1.11.1
# kubernetes networks addons
$ docker pull quay.io/calico/typha:v0.7.4
$ docker pull quay.io/calico/node:v3.1.3
$ docker pull quay.io/calico/cni:v3.1.3
# kubernetes metrics server
$ docker pull gcr.io/google_containers/metrics-server-amd64:v0.2.1
# kubernetes dashboard
$ docker pull gcr.io/google_containers/kubernetes-dashboard-amd64:v1.8.3
# kubernetes heapster
$ docker pull k8s.gcr.io/heapster-amd64:v1.5.4
$ docker pull k8s.gcr.io/heapster-influxdb-amd64:v1.5.2
$ docker pull k8s.gcr.io/heapster-grafana-amd64:v5.0.4
# kubernetes apiserver load balancer
$ docker pull nginx:latest
# prometheus
$ docker pull prom/prometheus:v2.3.1
# traefik
$ docker pull traefik:v1.6.3
# istio
$ docker pull docker.io/jaegertracing/all-in-one:1.5
$ docker pull docker.io/prom/prometheus:v2.3.1
$ docker pull docker.io/prom/statsd-exporter:v0.6.0
$ docker pull gcr.io/istio-release/citadel:1.0.0
$ docker pull gcr.io/istio-release/galley:1.0.0
$ docker pull gcr.io/istio-release/grafana:1.0.0
$ docker pull gcr.io/istio-release/mixer:1.0.0
$ docker pull gcr.io/istio-release/pilot:1.0.0
$ docker pull gcr.io/istio-release/proxy_init:1.0.0
$ docker pull gcr.io/istio-release/proxyv2:1.0.0
$ docker pull gcr.io/istio-release/servicegraph:1.0.0
$ docker pull gcr.io/istio-release/sidecar_injector:1.0.0
$ docker pull quay.io/coreos/hyperkube:v1.7.6_coreos.0
- on all kubernetes nodes: add kubernetes' repository
$ cat <<EOF > /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=https://packages.cloud.google.com/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://packages.cloud.google.com/yum/doc/yum-key.gpg https://packages.cloud.google.com/yum/doc/rpm-package-key.gpg
exclude=kube*
EOF
- on all kubernetes nodes: update system
$ yum update -y
- on all kubernetes nodes: set SELINUX to permissive mode
$ vi /etc/selinux/config
SELINUX=permissive
$ setenforce 0
- on all kubernetes nodes: set iptables parameters
$ cat <<EOF > /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_forward = 1
EOF
$ sysctl --system
- on all kubernetes nodes: disable swap
$ swapoff -a
# disable swap mount point in /etc/fstab
$ vi /etc/fstab
#/dev/mapper/centos-swap swap swap defaults 0 0
# check swap is disabled
$ cat /proc/swaps
Filename Type Size Used Priority
- on all kubernetes nodes: reboot hosts
# reboot hosts
$ reboot
- on all kubernetes nodes: enable firewalld
# restart firewalld service
$ systemctl enable firewalld
$ systemctl restart firewalld
$ systemctl status firewalld
- master ports list
Protocol | Direction | Port | Comment |
---|---|---|---|
TCP | Inbound | 16443* | Load balancer Kubernetes API server port |
TCP | Inbound | 6443* | Kubernetes API server |
TCP | Inbound | 4001 | etcd listen client port |
TCP | Inbound | 2379-2380 | etcd server client API |
TCP | Inbound | 10250 | Kubelet API |
TCP | Inbound | 10251 | kube-scheduler |
TCP | Inbound | 10252 | kube-controller-manager |
TCP | Inbound | 10255 | Read-only Kubelet API (Deprecated) |
TCP | Inbound | 30000-32767 | NodePort Services |
- on all master nodes: set firewalld policy
$ firewall-cmd --zone=public --add-port=16443/tcp --permanent
$ firewall-cmd --zone=public --add-port=6443/tcp --permanent
$ firewall-cmd --zone=public --add-port=4001/tcp --permanent
$ firewall-cmd --zone=public --add-port=2379-2380/tcp --permanent
$ firewall-cmd --zone=public --add-port=10250/tcp --permanent
$ firewall-cmd --zone=public --add-port=10251/tcp --permanent
$ firewall-cmd --zone=public --add-port=10252/tcp --permanent
$ firewall-cmd --zone=public --add-port=30000-32767/tcp --permanent
$ firewall-cmd --reload
$ firewall-cmd --list-all --zone=public
public (active)
target: default
icmp-block-inversion: no
interfaces: ens2f1 ens1f0 nm-bond
sources:
services: ssh dhcpv6-client
ports: 4001/tcp 6443/tcp 2379-2380/tcp 10250/tcp 10251/tcp 10252/tcp 30000-32767/tcp
protocols:
masquerade: no
forward-ports:
source-ports:
icmp-blocks:
rich rules:
- worker ports list
Protocol | Direction | Port | Comment |
---|---|---|---|
TCP | Inbound | 10250 | Kubelet API |
TCP | Inbound | 30000-32767 | NodePort Services |
- on all worker nodes: set firewalld policy
$ firewall-cmd --zone=public --add-port=10250/tcp --permanent
$ firewall-cmd --zone=public --add-port=30000-32767/tcp --permanent
$ firewall-cmd --reload
$ firewall-cmd --list-all --zone=public
public (active)
target: default
icmp-block-inversion: no
interfaces: ens2f1 ens1f0 nm-bond
sources:
services: ssh dhcpv6-client
ports: 10250/tcp 30000-32767/tcp
protocols:
masquerade: no
forward-ports:
source-ports:
icmp-blocks:
rich rules:
- on all kubernetes nodes: set firewalld to enable kube-proxy port forward
$ firewall-cmd --permanent --direct --add-rule ipv4 filter INPUT 1 -i docker0 -j ACCEPT -m comment --comment "kube-proxy redirects"
$ firewall-cmd --permanent --direct --add-rule ipv4 filter FORWARD 1 -o docker0 -j ACCEPT -m comment --comment "docker subnet"
$ firewall-cmd --reload
$ firewall-cmd --direct --get-all-rules
ipv4 filter INPUT 1 -i docker0 -j ACCEPT -m comment --comment 'kube-proxy redirects'
ipv4 filter FORWARD 1 -o docker0 -j ACCEPT -m comment --comment 'docker subnet'
# restart firewalld service
$ systemctl restart firewalld
- on all kubernetes nodes: remove this iptables chains, this settings will prevent kube-proxy node port forward. ( Notice: please run this command each time you restart firewalld ) Let's set the crontab.
$ crontab -e
0,5,10,15,20,25,30,35,40,45,50,55 * * * * /usr/sbin/iptables -D INPUT -j REJECT --reject-with icmp-host-prohibited
- on all kubernetes nodes: install kubernetes and related services, then start up kubelet and docker daemon
$ yum install -y docker-ce-17.12.0.ce-0.2.rc2.el7.centos.x86_64
$ yum install -y docker-compose-1.9.0-5.el7.noarch
$ systemctl enable docker && systemctl start docker
$ yum install -y kubelet-1.11.1-0.x86_64 kubeadm-1.11.1-0.x86_64 kubectl-1.11.1-0.x86_64
$ systemctl enable kubelet && systemctl start kubelet
- on all master nodes: install and start keepalived service
$ yum install -y keepalived
$ systemctl enable keepalived && systemctl restart keepalived
- on k8s-master01: set hosts mutual trust
$ rm -rf /root/.ssh/*
$ ssh k8s-master01 pwd
$ ssh k8s-master02 rm -rf /root/.ssh/*
$ ssh k8s-master03 rm -rf /root/.ssh/*
$ ssh k8s-master02 mkdir -p /root/.ssh/
$ ssh k8s-master03 mkdir -p /root/.ssh/
$ scp /root/.ssh/known_hosts root@k8s-master02:/root/.ssh/
$ scp /root/.ssh/known_hosts root@k8s-master03:/root/.ssh/
$ ssh-keygen -t rsa -P '' -f /root/.ssh/id_rsa
$ cat /root/.ssh/id_rsa.pub >> /root/.ssh/authorized_keys
$ scp /root/.ssh/authorized_keys root@k8s-master02:/root/.ssh/
- on k8s-master02: set hosts mutual trust
$ ssh-keygen -t rsa -P '' -f /root/.ssh/id_rsa
$ cat /root/.ssh/id_rsa.pub >> /root/.ssh/authorized_keys
$ scp /root/.ssh/authorized_keys root@k8s-master03:/root/.ssh/
- on k8s-master03: set hosts mutual trust
$ ssh-keygen -t rsa -P '' -f /root/.ssh/id_rsa
$ cat /root/.ssh/id_rsa.pub >> /root/.ssh/authorized_keys
$ scp /root/.ssh/authorized_keys root@k8s-master01:/root/.ssh/
$ scp /root/.ssh/authorized_keys root@k8s-master02:/root/.ssh/
- on k8s-master01: clone kubeadm-ha project source code
$ git clone https://github.com/cookeem/kubeadm-ha
- on k8s-master01: use
create-config.sh
to create relative config files, this script will create all configuration files, follow the setting comment and make sure you set the parameters correctly.
$ cd kubeadm-ha
$ vi create-config.sh
# master keepalived virtual ip address
export K8SHA_VIP=192.168.60.79
# master01 ip address
export K8SHA_IP1=192.168.60.72
# master02 ip address
export K8SHA_IP2=192.168.60.77
# master03 ip address
export K8SHA_IP3=192.168.60.78
# master keepalived virtual ip hostname
export K8SHA_VHOST=k8s-master-lb
# master01 hostname
export K8SHA_HOST1=k8s-master01
# master02 hostname
export K8SHA_HOST2=k8s-master02
# master03 hostname
export K8SHA_HOST3=k8s-master03
# master01 network interface name
export K8SHA_NETINF1=nm-bond
# master02 network interface name
export K8SHA_NETINF2=nm-bond
# master03 network interface name
export K8SHA_NETINF3=nm-bond
# keepalived auth_pass config
export K8SHA_KEEPALIVED_AUTH=412f7dc3bfed32194d1600c483e10ad1d
# calico reachable ip address
export K8SHA_CALICO_REACHABLE_IP=192.168.60.1
# kubernetes CIDR pod subnet, if CIDR pod subnet is "172.168.0.0/16" please set to "172.168.0.0"
export K8SHA_CIDR=172.168.0.0
# run the shell, it will create 3 masters' kubeadm config files, keepalived config files, nginx load balance config files, and calico config files.
$ ./create-config.sh
create kubeadm-config.yaml files success. config/k8s-master01/kubeadm-config.yaml
create kubeadm-config.yaml files success. config/k8s-master02/kubeadm-config.yaml
create kubeadm-config.yaml files success. config/k8s-master03/kubeadm-config.yaml
create keepalived files success. config/k8s-master01/keepalived/
create keepalived files success. config/k8s-master02/keepalived/
create keepalived files success. config/k8s-master03/keepalived/
create nginx-lb files success. config/k8s-master01/nginx-lb/
create nginx-lb files success. config/k8s-master02/nginx-lb/
create nginx-lb files success. config/k8s-master03/nginx-lb/
create calico.yaml file success. calico/calico.yaml
# set hostname environment variables
$ export HOST1=k8s-master01
$ export HOST2=k8s-master02
$ export HOST3=k8s-master03
# copy kubeadm config files to all master nodes, path is /root/
$ scp -r config/$HOST1/kubeadm-config.yaml $HOST1:/root/
$ scp -r config/$HOST2/kubeadm-config.yaml $HOST2:/root/
$ scp -r config/$HOST3/kubeadm-config.yaml $HOST3:/root/
# copy keepalived config files to all master nodes, path is /etc/keepalived/
$ scp -r config/$HOST1/keepalived/* $HOST1:/etc/keepalived/
$ scp -r config/$HOST2/keepalived/* $HOST2:/etc/keepalived/
$ scp -r config/$HOST3/keepalived/* $HOST3:/etc/keepalived/
# copy nginx load balance config files to all master nodes, path is /etc/kubernetes/
$ scp -r config/$HOST1/nginx-lb/nginx-lb.conf $HOST1:/etc/kubernetes/
$ scp -r config/$HOST2/nginx-lb/nginx-lb.conf $HOST2:/etc/kubernetes/
$ scp -r config/$HOST3/nginx-lb/nginx-lb.conf $HOST3:/etc/kubernetes/
# copy nginx load balance deployment files to all master nodes, path is /etc/kubernetes/manifests/
$ scp -r config/$HOST1/nginx-lb/nginx-lb.yaml $HOST1:/etc/kubernetes/manifests/
$ scp -r config/$HOST2/nginx-lb/nginx-lb.yaml $HOST2:/etc/kubernetes/manifests/
$ scp -r config/$HOST3/nginx-lb/nginx-lb.yaml $HOST3:/etc/kubernetes/manifests/
- on k8s-master01: use kubeadm to init a kubernetes cluster
# notice: you must save the following output message: kubeadm join --token ${YOUR_TOKEN} --discovery-token-ca-cert-hash ${YOUR_DISCOVERY_TOKEN_CA_CERT_HASH} , this command will use lately.
$ kubeadm init --config /root/kubeadm-config.yaml
kubeadm join 192.168.20.20:6443 --token ${YOUR_TOKEN} --discovery-token-ca-cert-hash sha256:${YOUR_DISCOVERY_TOKEN_CA_CERT_HASH}
- on all master nodes: set kubectl client environment variable
$ cat <<EOF >> ~/.bashrc
export KUBECONFIG=/etc/kubernetes/admin.conf
EOF
$ source ~/.bashrc
# kubectl now can connect the kubernetes cluster
$ kubectl get nodes
- on k8s-master01: wait until etcd, kube-apiserver, kube-controller-manager, kube-scheduler startup
$ kubectl get pods -n kube-system -o wide
NAME READY STATUS RESTARTS AGE IP NODE
...
etcd-k8s-master01 1/1 Running 0 18m 192.168.20.20 k8s-master01
kube-apiserver-k8s-master01 1/1 Running 0 18m 192.168.20.20 k8s-master01
kube-controller-manager-k8s-master01 1/1 Running 0 18m 192.168.20.20 k8s-master01
kube-scheduler-k8s-master01 1/1 Running 1 18m 192.168.20.20 k8s-master01
...
- on k8s-master01: copy certificates to other master nodes
# set master nodes hostname
$ export CONTROL_PLANE_IPS="k8s-master02 k8s-master03"
# copy certificates to other master nodes
$ for host in ${CONTROL_PLANE_IPS}; do
scp /etc/kubernetes/pki/ca.crt $host:/etc/kubernetes/pki/ca.crt
scp /etc/kubernetes/pki/ca.key $host:/etc/kubernetes/pki/ca.key
scp /etc/kubernetes/pki/sa.key $host:/etc/kubernetes/pki/sa.key
scp /etc/kubernetes/pki/sa.pub $host:/etc/kubernetes/pki/sa.pub
scp /etc/kubernetes/pki/front-proxy-ca.crt $host:/etc/kubernetes/pki/front-proxy-ca.crt
scp /etc/kubernetes/pki/front-proxy-ca.key $host:/etc/kubernetes/pki/front-proxy-ca.key
scp /etc/kubernetes/pki/etcd/ca.crt $host:/etc/kubernetes/pki/etcd/ca.crt
scp /etc/kubernetes/pki/etcd/ca.key $host:/etc/kubernetes/pki/etcd/ca.key
scp /etc/kubernetes/admin.conf $host:/etc/kubernetes/admin.conf
done
- on k8s-master02: master node join the cluster
# create all certificates and kubelet config files
$ kubeadm alpha phase certs all --config /root/kubeadm-config.yaml
$ kubeadm alpha phase kubeconfig controller-manager --config /root/kubeadm-config.yaml
$ kubeadm alpha phase kubeconfig scheduler --config /root/kubeadm-config.yaml
$ kubeadm alpha phase kubelet config write-to-disk --config /root/kubeadm-config.yaml
$ kubeadm alpha phase kubelet write-env-file --config /root/kubeadm-config.yaml
$ kubeadm alpha phase kubeconfig kubelet --config /root/kubeadm-config.yaml
$ systemctl restart kubelet
# set k8s-master01 and k8s-master02 HOSTNAME and ip address
$ export CP0_IP=192.168.20.20
$ export CP0_HOSTNAME=k8s-master01
$ export CP1_IP=192.168.20.21
$ export CP1_HOSTNAME=k8s-master02
# add etcd member to the cluster
$ kubectl exec -n kube-system etcd-${CP0_HOSTNAME} -- etcdctl --ca-file /etc/kubernetes/pki/etcd/ca.crt --cert-file /etc/kubernetes/pki/etcd/peer.crt --key-file /etc/kubernetes/pki/etcd/peer.key --endpoints=https://${CP0_IP}:2379 member add ${CP1_HOSTNAME} https://${CP1_IP}:2380
$ kubeadm alpha phase etcd local --config /root/kubeadm-config.yaml
# prepare to start master
$ kubeadm alpha phase kubeconfig all --config /root/kubeadm-config.yaml
$ kubeadm alpha phase controlplane all --config /root/kubeadm-config.yaml
$ kubeadm alpha phase mark-master --config /root/kubeadm-config.yaml
# modify /etc/kubernetes/admin.conf server settings
$ sed -i "s/192.168.20.20:6443/192.168.20.21:6443/g" /etc/kubernetes/admin.conf
- on k8s-master03: master node join the cluster
# create all certificates and kubelet config files
$ kubeadm alpha phase certs all --config /root/kubeadm-config.yaml
$ kubeadm alpha phase kubeconfig controller-manager --config /root/kubeadm-config.yaml
$ kubeadm alpha phase kubeconfig scheduler --config /root/kubeadm-config.yaml
$ kubeadm alpha phase kubelet config write-to-disk --config /root/kubeadm-config.yaml
$ kubeadm alpha phase kubelet write-env-file --config /root/kubeadm-config.yaml
$ kubeadm alpha phase kubeconfig kubelet --config /root/kubeadm-config.yaml
$ systemctl restart kubelet
# set k8s-master01 and k8s-master03 HOSTNAME and ip address
$ export CP0_IP=192.168.20.20
$ export CP0_HOSTNAME=k8s-master01
$ export CP2_IP=192.168.20.22
$ export CP2_HOSTNAME=k8s-master03
# add etcd member to the cluster
$ kubectl exec -n kube-system etcd-${CP0_HOSTNAME} -- etcdctl --ca-file /etc/kubernetes/pki/etcd/ca.crt --cert-file /etc/kubernetes/pki/etcd/peer.crt --key-file /etc/kubernetes/pki/etcd/peer.key --endpoints=https://${CP0_IP}:2379 member add ${CP2_HOSTNAME} https://${CP2_IP}:2380
$ kubeadm alpha phase etcd local --config /root/kubeadm-config.yaml
# prepare to start master
$ kubeadm alpha phase kubeconfig all --config /root/kubeadm-config.yaml
$ kubeadm alpha phase controlplane all --config /root/kubeadm-config.yaml
$ kubeadm alpha phase mark-master --config /root/kubeadm-config.yaml
# modify /etc/kubernetes/admin.conf server settings
$ sed -i "s/192.168.20.20:6443/192.168.20.22:6443/g" /etc/kubernetes/admin.conf
- on all master nodes: enable hpa to collect performance data form apiserver, add config below in file
/etc/kubernetes/manifests/kube-controller-manager.yaml
$ vi /etc/kubernetes/manifests/kube-controller-manager.yaml
- --horizontal-pod-autoscaler-use-rest-clients=false
- on all master nodes: enable istio auto-injection, add config below in file
/etc/kubernetes/manifests/kube-apiserver.yaml
$ vi /etc/kubernetes/manifests/kube-apiserver.yaml
- --enable-admission-plugins=NamespaceLifecycle,LimitRanger,ServiceAccount,DefaultStorageClass,DefaultTolerationSeconds,MutatingAdmissionWebhook,ValidatingAdmissionWebhook,ResourceQuota
# restart kubelet service
systemctl restart kubelet
- on any master nodes: install calico network addon, after network addon installed the cluster nodes status will be
READY
$ kubectl apply -f calico/
- on all master nodes: restart keepalived service
$ systemctl restart keepalived
$ systemctl status keepalived
# check keepalived vip
$ curl -k https://k8s-master-lb:6443
- nginx load balancer is self-hosted by kubelet
$ curl -k https://k8s-master-lb:16443
---
[category](#category)
#### kube-proxy HA settings
- on any master nodes: set kube-proxy server settings, make sure this settings use the keepalived virtual IP and nginx load balancer port (here is: https://192.168.20.10:16443)
```sh
$ kubectl edit -n kube-system configmap/kube-proxy
server: https://192.168.20.10:16443
- on any master nodes: restart kube-proxy pods
# find all kube-proxy pods
$ kubectl get pods --all-namespaces -o wide | grep proxy
# delete and restart all kube-proxy pods
$ kubectl delete pod -n kube-system kube-proxy-XXX
- on any master nodes: check cluster running status
# check kubernetes nodes status
$ kubectl get nodes
NAME STATUS ROLES AGE VERSION
k8s-master01 Ready master 1h v1.11.1
k8s-master02 Ready master 58m v1.11.1
k8s-master03 Ready master 55m v1.11.1
# check kube-system pods running status
$ kubectl get pods -n kube-system -o wide
NAME READY STATUS RESTARTS AGE IP NODE
calico-node-nxskr 2/2 Running 0 46m 192.168.20.22 k8s-master03
calico-node-xv5xt 2/2 Running 0 46m 192.168.20.20 k8s-master01
calico-node-zsmgp 2/2 Running 0 46m 192.168.20.21 k8s-master02
coredns-78fcdf6894-kfzc7 1/1 Running 0 1h 172.168.2.3 k8s-master03
coredns-78fcdf6894-t957l 1/1 Running 0 46m 172.168.1.2 k8s-master02
etcd-k8s-master01 1/1 Running 0 1h 192.168.20.20 k8s-master01
etcd-k8s-master02 1/1 Running 0 58m 192.168.20.21 k8s-master02
etcd-k8s-master03 1/1 Running 0 54m 192.168.20.22 k8s-master03
kube-apiserver-k8s-master01 1/1 Running 0 52m 192.168.20.20 k8s-master01
kube-apiserver-k8s-master02 1/1 Running 0 52m 192.168.20.21 k8s-master02
kube-apiserver-k8s-master03 1/1 Running 0 51m 192.168.20.22 k8s-master03
kube-controller-manager-k8s-master01 1/1 Running 0 34m 192.168.20.20 k8s-master01
kube-controller-manager-k8s-master02 1/1 Running 0 33m 192.168.20.21 k8s-master02
kube-controller-manager-k8s-master03 1/1 Running 0 33m 192.168.20.22 k8s-master03
kube-proxy-g9749 1/1 Running 0 36m 192.168.20.22 k8s-master03
kube-proxy-lhzhb 1/1 Running 0 35m 192.168.20.20 k8s-master01
kube-proxy-x8jwt 1/1 Running 0 36m 192.168.20.21 k8s-master02
kube-scheduler-k8s-master01 1/1 Running 1 1h 192.168.20.20 k8s-master01
kube-scheduler-k8s-master02 1/1 Running 0 57m 192.168.20.21 k8s-master02
kube-scheduler-k8s-master03 1/1 Running 1 54m 192.168.20.22 k8s-master03
- on any master nodes: enable master node pod schedulable
$ kubectl taint nodes --all node-role.kubernetes.io/master-
- on any master nodes: install metrics-server, after v1.11.0 heapster is deprecated for performance data collection, it use metrics-server
$ kubectl apply -f metrics-server/
# wait for 5 minutes, use kubectl top to check the pod performance usage
$ kubectl top pods -n kube-system
NAME CPU(cores) MEMORY(bytes)
calico-node-wkstv 47m 113Mi
calico-node-x2sn5 36m 104Mi
calico-node-xnh6s 32m 106Mi
coredns-78fcdf6894-2xc6s 14m 30Mi
coredns-78fcdf6894-rk6ch 10m 22Mi
kube-apiserver-k8s-master01 163m 816Mi
kube-apiserver-k8s-master02 79m 617Mi
kube-apiserver-k8s-master03 73m 614Mi
kube-controller-manager-k8s-master01 52m 141Mi
kube-controller-manager-k8s-master02 0m 14Mi
kube-controller-manager-k8s-master03 0m 13Mi
kube-proxy-269t2 4m 21Mi
kube-proxy-6jc8n 9m 37Mi
kube-proxy-7n8xb 9m 39Mi
kube-scheduler-k8s-master01 20m 25Mi
kube-scheduler-k8s-master02 15m 19Mi
kube-scheduler-k8s-master03 15m 19Mi
metrics-server-77b77f5fc6-jm8t6 3m 43Mi
- on any master nodes: install heapster, after v1.11.0 heapster is deprecated for performance data collection, it use metrics-server. But kube-dashboard use heapster to display performance info, so we install it.
# install heapster, wait for 5 minutes
$ kubectl apply -f heapster/
- on any master nodes: install kube-dashboard
# install kube-dashboard
$ kubectl apply -f dashboard/
after install, open kube-dashboard in web browser, it need to login with token: https://k8s-master-lb:30000/
- on any master nodes: get kube-dashboard login token
# get kube-dashboard login token
$ kubectl -n kube-system describe secret $(kubectl -n kube-system get secret | grep admin-user | awk '{print $1}')
login to kube-dashboard, you can see all pods performance metrics
- on any master nodes: install traefik
# create k8s-master-lb domain certificate
$ openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout tls.key -out tls.crt -subj "/CN=k8s-master-lb"
# create kubernetes secret
kubectl -n kube-system create secret generic traefik-cert --from-file=tls.key --from-file=tls.crt
# install traefik
$ kubectl apply -f traefik/
after install use web browser to open traefik admin webUI: http://k8s-master-lb:30011/
- on any master nodes: install istio
# install istio
$ kubectl apply -f istio/
# check all istio pods
$ kubectl get pods -n istio-system
NAME READY STATUS RESTARTS AGE
grafana-69c856fc69-jbx49 1/1 Running 1 21m
istio-citadel-7c4fc8957b-vdbhp 1/1 Running 1 21m
istio-cleanup-secrets-5g95n 0/1 Completed 0 21m
istio-egressgateway-64674bd988-44fg8 1/1 Running 0 18m
istio-egressgateway-64674bd988-dgvfm 1/1 Running 1 16m
istio-egressgateway-64674bd988-fprtc 1/1 Running 0 18m
istio-egressgateway-64674bd988-kl6pw 1/1 Running 3 16m
istio-egressgateway-64674bd988-nphpk 1/1 Running 3 16m
istio-galley-595b94cddf-c5ctw 1/1 Running 70 21m
istio-grafana-post-install-nhs47 0/1 Completed 0 21m
istio-ingressgateway-4vtk5 1/1 Running 2 21m
istio-ingressgateway-5rscp 1/1 Running 3 21m
istio-ingressgateway-6z95f 1/1 Running 3 21m
istio-policy-589977bff5-jx5fd 2/2 Running 3 21m
istio-policy-589977bff5-n74q8 2/2 Running 3 21m
istio-sidecar-injector-86c4d57d56-mfnbp 1/1 Running 39 21m
istio-statsd-prom-bridge-5698d5798c-xdpp6 1/1 Running 1 21m
istio-telemetry-85d6475bfd-8lvsm 2/2 Running 2 21m
istio-telemetry-85d6475bfd-bfjsn 2/2 Running 2 21m
istio-telemetry-85d6475bfd-d9ld9 2/2 Running 2 21m
istio-tracing-bd5765b5b-cmszp 1/1 Running 1 21m
prometheus-77c5fc7cd-zf7zr 1/1 Running 1 21m
servicegraph-6b99c87849-l6zm6 1/1 Running 1 21m
- on any master nodes: install prometheus
# install prometheus
$ kubectl apply -f prometheus/
after install, open prometheus admin webUI: http://k8s-master-lb:30013/
open grafana admin webUI (user and password is
admin
): http://k8s-master-lb:30006/ after login, add prometheus datasource: http://k8s-master-lb:30006/datasources
import dashboard: http://k8s-master-lb:30006/dashboard/import import all files under
heapster/grafana-dashboard
directory, dashboardKubernetes App Metrics
,Kubernetes cluster monitoring (via Prometheus)
dashboard you imported:
- on all worker nodes: join kubernetes cluster
$ kubeadm reset
# use kubeadm to join the cluster, here we use the k8s-master01 apiserver address and port.
$ kubeadm join 192.168.20.20:6443 --token ${YOUR_TOKEN} --discovery-token-ca-cert-hash sha256:${YOUR_DISCOVERY_TOKEN_CA_CERT_HASH}
# set the `/etc/kubernetes/*.conf` server settings, make sure this settings use the keepalived virtual IP and nginx load balancer port (here is: https://192.168.20.10:16443)
$ sed -i "s/192.168.20.20:6443/192.168.20.10:16443/g" /etc/kubernetes/bootstrap-kubelet.conf
$ sed -i "s/192.168.20.20:6443/192.168.20.10:16443/g" /etc/kubernetes/kubelet.conf
# restart docker and kubelet service
$ systemctl restart docker kubelet
- on any master nodes: check all nodes status
$ kubectl get nodes
NAME STATUS ROLES AGE VERSION
k8s-master01 Ready master 1h v1.11.1
k8s-master02 Ready master 58m v1.11.1
k8s-master03 Ready master 55m v1.11.1
k8s-node01 Ready <none> 30m v1.11.1
k8s-node02 Ready <none> 24m v1.11.1
k8s-node03 Ready <none> 22m v1.11.1
k8s-node04 Ready <none> 22m v1.11.1
k8s-node05 Ready <none> 16m v1.11.1
k8s-node06 Ready <none> 13m v1.11.1
k8s-node07 Ready <none> 11m v1.11.1
k8s-node08 Ready <none> 10m v1.11.1
- NodePort testing
# create a nginx deployment, replicas=3
$ kubectl run nginx --image=nginx --replicas=3 --port=80
deployment "nginx" created
# check nginx pods status
$ kubectl get pods -l=run=nginx -o wide
NAME READY STATUS RESTARTS AGE IP NODE
nginx-58b94844fd-jvlqh 1/1 Running 0 9s 172.168.7.2 k8s-node05
nginx-58b94844fd-mkt72 1/1 Running 0 9s 172.168.9.2 k8s-node07
nginx-58b94844fd-xhb8x 1/1 Running 0 9s 172.168.11.2 k8s-node09
# create nginx NodePort service
$ kubectl expose deployment nginx --type=NodePort --port=80
service "nginx" exposed
# check nginx service status
$ kubectl get svc -l=run=nginx -o wide
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
nginx NodePort 10.106.129.121 <none> 80:31443/TCP 7s run=nginx
# check nginx NodePort service accessibility
$ curl k8s-master-lb:31443
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
body {
width: 35em;
margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif;
}
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>
<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>
<p><em>Thank you for using nginx.</em></p>
</body>
</html>
- pods connectivity testing
kubectl run nginx-client -ti --rm --image=alpine -- ash
/ # wget -O - nginx
Connecting to nginx (10.102.101.78:80)
index.html 100% |*****************************************| 612 0:00:00 ETA
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
body {
width: 35em;
margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif;
}
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>
<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>
<p><em>Thank you for using nginx.</em></p>
</body>
</html>
# remove all test nginx deployment and service
kubectl delete deploy,svc nginx
- HPA testing
# create test nginx-server
kubectl run nginx-server --requests=cpu=10m --image=nginx --port=80
kubectl expose deployment nginx-server --port=80
# create hpa
kubectl autoscale deployment nginx-server --cpu-percent=10 --min=1 --max=10
kubectl get hpa
kubectl describe hpa nginx-server
# increase nginx-server load
kubectl run -ti --rm load-generator --image=busybox -- ash
wget -q -O- http://nginx-server.default.svc.cluster.local > /dev/null
while true; do wget -q -O- http://nginx-server.default.svc.cluster.local > /dev/null; done
# it may take a few minutes to stabilize the number of replicas. Since the amount of load is not controlled in any way it may happen that the final number of replicas will differ from this example.
kubectl get hpa -w
# remove all test deployment service and HPA
kubectl delete deploy,svc,hpa nginx-server
- now kubernetes high availiability cluster setup successfully 😃