Bootstrapping etcd

Download etcd

wget -q --show-progress --https-only --timestamping \
 "https://github.com/etcd-io/etcd/releases/download/v3.4.16/etcd-v3.4.16-linux-amd64.tar.gz"

systems startup script for etcd

INTERNAL_IP=$(ifconfig ens4 | grep -v inet6 |grep 'inet' | tr -s ' ' | cut -d' ' -f3)
cat <<EOF | sudo tee /etc/systemd/system/etcd.service
[Unit]
Description=etcd
Documentation=https://github.com/coreos

[Service]
Type=notify
ExecStart=/usr/local/bin/etcd \\
  --name ${ETCD_NAME} \\
  --cert-file=/etc/etcd/kubernetes.pem \\
  --key-file=/etc/etcd/kubernetes-key.pem \\
  --peer-cert-file=/etc/etcd/kubernetes.pem \\
  --peer-key-file=/etc/etcd/kubernetes-key.pem \\
  --trusted-ca-file=/etc/etcd/ca.pem \\
  --peer-trusted-ca-file=/etc/etcd/ca.pem \\
  --peer-client-cert-auth \\
  --client-cert-auth \\
  --initial-advertise-peer-urls https://${INTERNAL_IP}:2380 \\
  --listen-peer-urls https://${INTERNAL_IP}:2380 \\
  --listen-client-urls https://${INTERNAL_IP}:2379,https://127.0.0.1:2379 \\
  --advertise-client-urls https://${INTERNAL_IP}:2379 \\
  --initial-cluster-token etcd-cluster-0 \\
  --initial-cluster us-etcd-01=https://10.1.20.11:2380,us-etcd-02=https://10.1.20.12:2380,us-etcd-03=https://10.1.20.10:2380 \\
  --initial-cluster-state new \\
  --data-dir=/var/lib/etcd
Restart=on-failure
RestartSec=5

[Install]
WantedBy=multi-user.target
EOF

Validate etcd Installation

sudo ETCDCTL_API=3 etcdctl endpoint status --cluster -w table --cacert=/etc/etcd/ca.pem --cert=/etc/etcd/etcd.pem --key=/etc/etcd/etcd-key.pem

 +-------------------------+------------------+---------+---------+-----------+------------+-----------+------------+--------------------+--------+
 |        ENDPOINT         |        ID        | VERSION | DB SIZE | IS LEADER | IS LEARNER | RAFT TERM | RAFT INDEX | RAFT APPLIED INDEX | ERRORS |
 +-------------------------+------------------+---------+---------+-----------+------------+-----------+------------+--------------------+--------+
 | https://10.1.20.12:2379 | 29458c1e3b5d42da |   3.4.9 |  5.3 MB |     false |      false |      3152 |      39760 |              39760 |        |
 | https://10.1.20.10:2379 | 2b1ec301a82f6187 |   3.4.9 |  5.3 MB |     false |      false |      3152 |      39760 |              39760 |        |
 | https://10.1.20.11:2379 | bbd865a60d3517fb |   3.4.9 |  5.3 MB |      true |      false |      3152 |      39760 |              39760 |        |
 +-------------------------+------------------+---------+---------+-----------+------------+-----------+------------+--------------------+--------+