Basic installation

On Centos7, RPMs are from Ceontos7 extras repository

1 master, 2 nodes

RPM verisons

On master:
- kubernetes-master, kubernetes-client - 1.5.2-0.2.gitc55cf2b.el7
- etc - 3.1.0-2.el7
- flannel - 0.7.0-1.el7
On nodes:
- kubernetes-client, kubernetes-node - 1.5.2-0.2.gitc55cf2b.el7

Hostnames, IP, subnets, IP ranges

master and node IPs
- master: node-1(192.168.50.101/24, IP address is on eth1)
- nodes: node2(192.168.50.102/24), node-3(192.168.50.103/24), IP Address are on eth1
kubernetes cluster IP range: 10.254.0.0/16
flannel: iface on eth1, range: 172.30.0.0/16, subnetLen:24, type: vxlan

Ports

etcd: 2379
kube-apiserver: 8080
kubelet: 10250

Services

On master:
- etcd
- kube-apiserver
- kube-controller-manager
- kube-scheduler
- flanneld
On nodes:
- kubelet
- kube-proxy
- flanneld

configuration files

/etc/etcd/etcd.conf

ETCD_NAME=default
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
ETCD_LISTEN_CLIENT_URLS="http://localhost:2379,http://node-1:2379"
ETCD_ADVERTISE_CLIENT_URLS="http://localhost:2379,http://node-1:2379"

/etc/kubernetes/config - for both master and node

KUBE_LOGTOSTDERR="--logtostderr=true"
KUBE_LOG_LEVEL="--v=0"
KUBE_ALLOW_PRIV="--allow-privileged=false"
KUBE_MASTER="--master=http://node-1:8080"

/etc/kubernetes/apiserver

KUBE_API_ADDRESS="--insecure-bind-address=0.0.0.0"
KUBE_ETCD_SERVERS="--etcd-servers=http://node-1:2379"
KUBE_SERVICE_ADDRESSES="--service-cluster-ip-range=10.254.0.0/16"
KUBE_API_ARGS=""
KUBE_API_PORT="--port=8080"
KUBELET_PORT="--kubelet-port=10250"

/etc/controller-manager
```
KUBE_CONTROLLER_MANAGER_ARGS=""
```
/etc/scheduler
```
KUBE_SCHEDULER_ARGS=""
```

/etc/kubernetes/kubelet

KUBELET_ADDRESS="--address=0.0.0.0"
KUBELET_HOSTNAME="--hostname-override=node-2"
KUBELET_API_SERVER="--api-servers=http://node-1:8080"
KUBELET_ARGS=""
KUBELET_PORT="--port=10250"

/etc/kubernetes/proxy
```
KUBE_PROXY_ARGS=""
```

/etc/sysconfig/flanneld

FLANNEL_ETCD_ENDPOINTS="http://node-1:2379"
FLANNEL_ETCD_PREFIX="/kube-centos/network"
FLANNEL_OPTIONS="-iface=eth1"

manual step to configure flannel with etcd

# systemctl start etcd
# etcdctl mkdir /kube-centos/network
# etcdctl mk /kube-centos/network/config "{ \"Network\": \"172.30.0.0/16\", \"SubnetLen\": 24, \"Backend\": { \"Type\": \"vxlan\" } }"

service processes

master

/usr/bin/etcd --name=default --data-dir=/var/lib/etcd/default.etcd --listen-client-urls=http://localhost:2379,http://node-1:2379
usr/bin/kube-apiserver --logtostderr=true --v=0 --etcd-servers=http://node-1:2379 --insecure-bind-address=0.0.0.0 --port=8080 --kubelet-port=10250 --allow-privileged=false --service-cluster-ip-range=10.254.0.0/16
/usr/bin/kube-controller-manager --logtostderr=true --v=0 --master=http://node-1:8080
/usr/bin/kube-scheduler --logtostderr=true --v=0 --master=http://node-1:8080
/usr/bin/flanneld -etcd-endpoints=http://node-1:2379 -etcd-prefix=/kube-centos/network -iface=eth1

nodes

/usr/bin/kubelet --logtostderr=true --v=0 --api-servers=http://node-1:8080 --address=0.0.0.0 --port=10250 --hostname-override=node-2 --allow-privileged=false
/usr/bin/kube-proxy --logtostderr=true --v=0 --master=http://node-1:8080
/usr/bin/flanneld -etcd-endpoints=http://node-1:2379 -etcd-prefix=/kube-centos/network -iface=eth1

First pod - Hello Kubernetes!

$ kubectl run node-hello --image=gcr.io/google-samples/node-hello:1.0 --port=8080

$ kubectl get deploy
NAME         DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGE
node-hello   1         1         1            1           1h

$ kubectl get po
NAME                          READY     STATUS    RESTARTS   AGE
node-hello-3526609615-fqf4k   1/1       Running   0          1h


$ kubectl expose deploy/node-hello --type=NodePort
service "node-hello" exposed

$ kubectl get svc -l run=node-hello
NAME         CLUSTER-IP     EXTERNAL-IP   PORT(S)          AGE
hello-node   10.254.139.8   <nodes>       8080:30881/TCP   11s

$ kubectl get po -l run=node-hello -o wide
NAME                          READY     STATUS    RESTARTS   AGE       IP           NODE
node-hello-3526609615-fqf4k   1/1       Running   0          1h        172.30.5.2   node-3

$ curl http://node-3:30881
Hello Kubernetes!

$ curl http://node-2:30881
Hello Kubernetes!

2nd pod with replicas

$ kubectl run kubernetes-bootcamp --image=jocatalin/kubernetes-bootcamp:v1 --port=8080
deployment "kubernetes-bootcamp" created

$ kubectl get deploy
NAME                  DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGE
kubernetes-bootcamp   1         1         1            1           16s


$ kubectl get po
NAME                                   READY     STATUS    RESTARTS   AGE
kubernetes-bootcamp-2019480069-jtswf   1/1       Running   0          18s

$ kubectl expose deploy/kubernetes-bootcamp --type=NodePort
service "kubernetes-bootcamp" exposed

$ kubectl get svc
NAME                  CLUSTER-IP       EXTERNAL-IP   PORT(S)          AGE
kubernetes            10.254.0.1       <none>        443/TCP          1h
kubernetes-bootcamp   10.254.195.177   <nodes>       8080:32693/TCP   13s

$ kubectl get po -o wide
NAME                                   READY     STATUS    RESTARTS   AGE       IP            NODE
kubernetes-bootcamp-2019480069-jtswf   1/1       Running   0          1m        172.30.93.2   node-2

$ curl http://node-2:32693
Hello Kubernetes bootcamp! | Running on: kubernetes-bootcamp-2019480069-jtswf | v=1
$ curl http://node-2:32693
Hello Kubernetes bootcamp! | Running on: kubernetes-bootcamp-2019480069-jtswf | v=1
$ kubectl logs kubernetes-bootcamp-2019480069-jtswf
Kubernetes Bootcamp App Started At: 2017-04-04T19:45:42.811Z | Running On:  kubernetes-bootcamp-2019480069-jtswf 
Running On: kubernetes-bootcamp-2019480069-jtswf | Total Requests: 1 | App Uptime: 112.899 seconds | Log Time: 2017-04-04T19:47:35.710Z
Running On: kubernetes-bootcamp-2019480069-jtswf | Total Requests: 2 | App Uptime: 127.612 seconds | Log Time: 2017-04-04T19:47:50.423Z

$ kubectl scale deploy/kubernetes-bootcamp --replicas=4
deployment "kubernetes-bootcamp" scaled

$ kubectl get po -o wide
NAME                                   READY     STATUS    RESTARTS   AGE       IP            NODE
kubernetes-bootcamp-2019480069-220qd   1/1       Running   0          57m       172.30.5.3    node-3
kubernetes-bootcamp-2019480069-ftzgl   1/1       Running   0          57m       172.30.5.2    node-3
kubernetes-bootcamp-2019480069-jtswf   1/1       Running   0          59m       172.30.93.2   node-2
kubernetes-bootcamp-2019480069-k0gkq   1/1       Running   0          57m       172.30.93.3   node-2

$ curl http://node-2:32693
Hello Kubernetes bootcamp! | Running on: kubernetes-bootcamp-2019480069-ftzgl | v=1
$ curl http://node-3:32693
Hello Kubernetes bootcamp! | Running on: kubernetes-bootcamp-2019480069-220qd | v=1
$ curl http://node-3:32693
Hello Kubernetes bootcamp! | Running on: kubernetes-bootcamp-2019480069-k0gkq | v=1
$ curl http://node-2:32693
Hello Kubernetes bootcamp! | Running on: kubernetes-bootcamp-2019480069-jtswf | v=1