k8s-ansible

adjust my setting to match your environment group_vars/all 和inventory/hosts文件

Version used

K8S_SERVER_VER=1.18.3

ETCD_VER=3.4.9

FLANNEL_VER=0.12.0

CNI_PLUGIN_VER=0.8.6

CALICO_VER=3.15.0

DOCKER_VER=19.03.10

Subnet Info

pod subnet：10.244.0.0/16

service subnet：10.96.0.0/12

kubernetes internal IP：10.96.0.1

coredns address： 10.96.0.10

machines/instances

machine	IP	role and component	k8s realted components
centos7-nginx	10.10.10.127	nginx layer4 proxy	nginx ansible
centos7-a	10.10.10.128	master,node,etcd,flannel	kube-apiserver kube-controller-manager kube-scheduler kubelet kube-proxy
centos7-b	10.10.10.129	master,node,etcd,flannel	kube-apiserver kube-controller-manager kube-scheduler kubelet kube-proxy
centos7-c	10.10.10.130	master,node,etcd,flannel	kube-apiserver kube-controller-manager kube-scheduler kubelet kube-proxy
centos7-d	10.10.10.131	node,flannel	kubelet kube-proxy
centos7-e	10.10.10.132	node,flannel	kubelet kube-proxy

preparation

execute download_binary.sh script to download

bash download_binary.sh

If you cannot run download_binary, then go to /opt/pkg/

wget https://github.com/containernetworking/plugins/releases/download/v${CNI_PLUGIN_VER}/cni-plugins-linux-amd64-v${CNI_PLUGIN_VER}.tgz && \
wget https://github.com/coreos/flannel/releases/download/v${FLANNEL_VER}/flannel-v${FLANNEL_VER}-linux-amd64.tar.gz && \
wget https://dl.k8s.io/v${K8S_SERVER_VER}/kubernetes-server-linux-amd64.tar.gz && \
wget https://github.com/etcd-io/etcd/releases/download/v${ETCD_VER}/etcd-v${ETCD_VER}-linux-amd64.tar.gz && \
wget https://pkg.cfssl.org/R1.2/cfssl_linux-amd64 && \
wget https://pkg.cfssl.org/R1.2/cfssljson_linux-amd64 && \
wget https://pkg.cfssl.org/R1.2/cfssl-certinfo_linux-amd64 &&\
wget https://github.com/projectcalico/calicoctl/releases/download/v{CALICOCTL_VER}/calicoctl

then run tools/move_pkg.sh to unzip/extract

bash tools/move_pkg.sh

modify the hosts file on the control box

[root@centos7-nginx k8s-ansible]# cat /etc/hosts
127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6
10.10.10.127 centos7-nginx lb.5179.top inner-lb.5179.top ng.5179.top ng-inner.5179.top
10.10.10.128 centos7-a
10.10.10.129 centos7-b
10.10.10.130 centos7-c
10.10.10.131 centos7-d
10.10.10.132 centos7-e

execute

ansible-playbook -i inventory/hosts  site.yml

After the execution, we can see

[root@centos7-nginx k8s-ansible]# kubectl get nodes
NAME           STATUS   ROLES    AGE     VERSION
10.10.10.128   Ready    master   7m48s   v1.18.3
10.10.10.129   Ready    master   7m49s   v1.18.3
10.10.10.130   Ready    master   7m49s   v1.18.3
10.10.10.131   Ready    <none>   7m49s   v1.18.3
10.10.10.132   Ready    <none>   7m49s   v1.18.3

[root@centos7-nginx k8s-ansible]# kubectl describe nodes 10.10.10.128 |grep -C 3 Taints
Annotations:        node.alpha.kubernetes.io/ttl: 0
                    volumes.kubernetes.io/controller-managed-attach-detach: true
CreationTimestamp:  Thu, 25 Jun 2020 17:38:09 +0800
Taints:             node-role.kubernetes.io/master:NoSchedule
Unschedulable:      false
Lease:
  HolderIdentity:  10.10.10.128

add new nodes

modify invertory/hosts的[new-nodes] then run

ansible-playbook -i inventory/hosts new_nodes.yml

test cluster

[root@centos7-nginx k8s-ansible]# kubectl apply -f tests/myapp.yaml

basic validation

[root@centos7-nginx k8s-ansible]# kubectl exec -it busybox -- sh
/ #
/ # nslookup kubernetes
Server:    10.96.0.10
Address 1: 10.96.0.10 kube-dns.kube-system.svc.cluster.local

Name:      kubernetes
Address 1: 10.96.0.1 kubernetes.default.svc.cluster.local
/ # nslookup myapp
Server:    10.96.0.10
Address 1: 10.96.0.10 kube-dns.kube-system.svc.cluster.local

Name:      myapp
Address 1: 10.102.233.224 myapp.default.svc.cluster.local
/ #
/ # curl myapp/hostname.html
myapp-5cbd66595b-p6zlp

clean

bash ./tools/clean.sh