order the labs

docs/03-etcd.md

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+# Bootstrapping a H/A etcd cluster
+
+In this lab you will bootstrap a 3 node etcd cluster. The following virtual machines will be used:
+
+```
+gcloud compute instances list
+```
+
+````
+NAME   ZONE           MACHINE_TYPE   PREEMPTIBLE  INTERNAL_IP  EXTERNAL_IP      STATUS
+etcd0  us-central1-f  n1-standard-1               10.240.0.10  XXX.XXX.XXX.XXX  RUNNING
+etcd1  us-central1-f  n1-standard-1               10.240.0.11  XXX.XXX.XXX.XXX  RUNNING
+etcd2  us-central1-f  n1-standard-1               10.240.0.12  XXX.XXX.XXX.XXX  RUNNING
+````
+
+## Why
+
+All Kubernetes components are stateless which greatly simplifies managing a Kubernetes cluster. All state is stored
+in etcd, which is a database and must be treated special. etcd is being run on a dedicated set of machines for the 
+following reasons:
+
+* The etcd lifecycle is not tied to Kubernetes. We should be able to upgrade etcd independently of Kubernetes.
+* Scaling out etcd is different than scaling out the Kubernetes Control Plane.
+* Prevent other applications from taking up resources (CPU, Memory, I/O) required by etcd.
+
+## Provision the etcd Cluster
+
+Run the following commands on `etcd0`, `etcd1`, `etcd2`:
+
+> SSH into each machine using the `gcloud compute ssh` command
+
+Move the TLS certificates in place:
+
+```
+sudo mkdir -p /etc/etcd/
+```
+
+```
+sudo mv ca.pem kubernetes-key.pem kubernetes.pem /etc/etcd/
+```
+
+Download and install the etcd binaries:
+
+```
+wget https://github.com/coreos/etcd/releases/download/v3.0.1/etcd-v3.0.1-linux-amd64.tar.gz
+```
+
+```
+tar -xvf etcd-v3.0.1-linux-amd64.tar.gz
+```
+
+```
+sudo cp etcd-v3.0.1-linux-amd64/etcdctl /usr/bin/
+```
+
+```
+sudo cp etcd-v3.0.1-linux-amd64/etcd /usr/bin/
+```
+
+```
+sudo mkdir -p /var/lib/etcd
+```
+
+Create the etcd systemd unit file:
+
+
+```
+cat > etcd.service <<"EOF"
+[Unit]
+Description=etcd
+Documentation=https://github.com/coreos
+
+[Service]
+ExecStart=/usr/bin/etcd --name ETCD_NAME \
+  --cert-file=/etc/etcd/kubernetes.pem \
+  --key-file=/etc/etcd/kubernetes-key.pem \
+  --peer-cert-file=/etc/etcd/kubernetes.pem \
+  --peer-key-file=/etc/etcd/kubernetes-key.pem \
+  --trusted-ca-file=/etc/etcd/ca.pem \
+  --peer-trusted-ca-file=/etc/etcd/ca.pem \
+  --initial-advertise-peer-urls https://INTERNAL_IP:2380 \
+  --listen-peer-urls https://INTERNAL_IP:2380 \
+  --listen-client-urls https://INTERNAL_IP:2379,http://127.0.0.1:2379 \
+  --advertise-client-urls https://INTERNAL_IP:2379 \
+  --initial-cluster-token etcd-cluster-0 \
+  --initial-cluster etcd0=https://10.240.0.10:2380,etcd1=https://10.240.0.11:2380,etcd2=https://10.240.0.12:2380 \
+  --initial-cluster-state new \
+  --data-dir=/var/lib/etcd
+Restart=on-failure
+RestartSec=5
+
+[Install]
+WantedBy=multi-user.target
+EOF
+```
+
+```
+export INTERNAL_IP=$(curl -s -H "Metadata-Flavor: Google" \
+  http://metadata.google.internal/computeMetadata/v1/instance/network-interfaces/0/ip)
+```
+
+```
+export ETCD_NAME=$(hostname -s)
+```
+
+```
+sed -i s/INTERNAL_IP/$INTERNAL_IP/g etcd.service
+```
+
+```
+sed -i s/ETCD_NAME/$ETCD_NAME/g etcd.service
+```
+
+```
+sudo mv etcd.service /etc/systemd/system/
+```
+
+Start etcd:
+
+```
+sudo systemctl daemon-reload
+sudo systemctl enable etcd
+sudo systemctl start etcd
+```
+
+### Verification
+
+```
+sudo systemctl status etcd --no-pager
+```
+
+## Verification
+
+Once all 3 etcd nodes have been bootstrapped verify the etcd cluster is healthy:
+
+```
+gcloud compute ssh etcd0
+```
+
+```
+etcdctl --ca-file=/etc/etcd/ca.pem cluster-health
+```
+
+```
+member 3a57933972cb5131 is healthy: got healthy result from https://10.240.0.12:2379
+member f98dc20bce6225a0 is healthy: got healthy result from https://10.240.0.10:2379
+member ffed16798470cab5 is healthy: got healthy result from https://10.240.0.11:2379
+cluster is healthy
+```