站長資訊網(wǎng)kuberntes 系統(tǒng)使用 etcd 存儲所有數(shù)據(jù)，是最重要的組件之一，注意 etcd集群只能有奇數(shù)個節(jié)點(1,3,5…)，本文檔使用3個節(jié)點做集群。
一、基礎(chǔ)環(huán)境
軟件包
etcd下載地址：https://github.com/coreos/etcd/releases
服務(wù)器
架構(gòu)圖
二、生成etcd證書與私鑰
創(chuàng)建etcd配置文件
{ "CN": "etcd", "hosts": [ "127.0.0.1", "192.168.1.11", "192.168.1.12", "192.168.1.13", "etcd1", "etcd2", "etcd3" ], "key": { "algo": "rsa", "size": 2048 }, "names": [ { "C": "CN", "ST": "BeiJing", "L": "BeiJing", "O": "Ctyun", "OU": "ops" } ] }hosts：定授權(quán)使用該證書的 etcd 節(jié)點 IP(應(yīng)包含集群內(nèi)所有節(jié)點的IP與hostname)C：國家ST：省份L：城市O：公司OU：部門
生成私鑰、證書請求文件、證書
CA證書在前面的章節(jié)創(chuàng)建 Kubernetes證書相關(guān)(CFSSL)
cfssl gencert -ca=/opt/ssl/k8sca/ca.pem -ca-key=/opt/ssl/k8sca/ca-key.pem -config=/opt/ssl/k8sca/ca-config.json -profile=kubernetes /opt/ssl/etcd/etcd-csr.json | cfssljson -bare etcd-ca：指定CA證書路徑-ca-key：指定CAKey的路徑-config：指定CA證書簽署策略配置文件
二、啟動和配置etcd
創(chuàng)建etcd配置文件etcd.conf，此配置文件是定義一些變量，方便etcd.service文件中直接引用、方便后期維護。
配置文件的所有含義都在創(chuàng)建etcd.service配置文件后有詳解。
mkdir -p /etc/etcd vim /etc/etcd/etcd.conf # [member] ETCD_NAME=etcd1 ETCD_DATA_DIR="/var/lib/etcd" ETCD_LISTEN_PEER_URLS="https://192.168.1.11:2380" ETCD_LISTEN_CLIENT_URLS="https://192.168.1.11:2379" #[cluster] ETCD_INITIAL_ADVERTISE_PEER_URLS="https://192.168.1.11:2380" ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster" ETCD_ADVERTISE_CLIENT_URLS="https://192.168.1.11:2379"創(chuàng)建etcd.service配置文件
etcd.service的變量都是引用etcd配置文件中
mkdir /var/lib/etcd vim /usr/lib/systemd/system/etcd.service [Unit] Description=Etcd Server After=network.target After=network-online.target Wants=network-online.target Documentation=https://github.com/coreos [Service] Type=notify WorkingDirectory=${ETCD_DATA_DIR} EnvironmentFile=/etc/etcd/etcd.conf ExecStart=/usr/local/bin/etcd --name=etcd1 --cert-file=/opt/ssl/etcd/etcd.pem --key-file=/opt/ssl/etcd/etcd-key.pem --peer-cert-file=/opt/ssl/etcd/etcd.pem --peer-key-file=/opt/ssl/etcd/etcd-key.pem --trusted-ca-file=/opt/ssl/k8sca/ca.pem --peer-trusted-ca-file=/opt/ssl/k8sca/ca.pem --initial-advertise-peer-urls=${ETCD_INITIAL_ADVERTISE_PEER_URLS} --listen-peer-urls=${ETCD_LISTEN_PEER_URLS} --listen-client-urls=${ETCD_LISTEN_CLIENT_URLS},http://127.0.0.1:2379 --advertise-client-urls=${ETCD_ADVERTISE_CLIENT_URLS} --initial-cluster-token=${ETCD_INITIAL_CLUSTER_TOKEN} --initial-cluster etcd1=https://192.168.1.11:2380,etcd2=https://192.168.1.12:2380,etcd3=https://192.168.1.13:2380 --initial-cluster-state=new --data-dir=/var/lib/etcd Restart=on-failure RestartSec=5 LimitNOFILE=65536 [Install] WantedBy=multi-user.target--initial-cluster：集群當(dāng)中的其他節(jié)點--cert-file：etcd證書路徑--key-file：etcd私鑰路徑--peer-cert-file：對等證書(雙向證書)路徑--peer-key-file：對等證書(雙向證書)私鑰路徑--trusted-ca-file：作為客戶端時的CA證書路徑--peer-trusted-ca-file：對等證書的CA證書路徑--initial-advertise-peer-urls：列出集群成員通信的URL，用于通告集群其他成員--listen-peer-urls：用于監(jiān)聽集群其他成員的URL列表--listen-client-urls：用于監(jiān)聽客戶端通訊的URL列表--advertise-client-urls：通告客戶端的URL，用于列出所有客戶端--initial-cluster-token：etcd集群的初始集群令牌，服務(wù)器必須通過令牌才能加入etcd集群
啟動etcd集群
集群所有節(jié)點都配置好配置文件，同時啟動。
systemctl daemon-reload && systemctl enable etcd && systemctl start etcd不使用變量的配置方法
前面分別創(chuàng)建了/etc/etcd/etcd.conf與/var/lib/systemd/system/etcd.service兩個配置文件，且etcd.service引用了etcd.conf重定義的變量。
如若不想引用變量，可以不寫etcd.conf。僅創(chuàng)建etcd.service如下
[root@etcd1 k8sca]# cat /usr/lib/systemd/system/etcd.service [Unit] Description=Etcd Server After=network.target After=network-online.target Wants=network-online.target Documentation=https://github.com/coreos [Service] Type=notify WorkingDirectory=/var/lib/etcd/ ExecStart=/usr/local/bin/etcd --name etcd1 --cert-file=/opt/ssl/etcd/etcd.pem --key-file=/opt/ssl/etcd/etcd-key.pem --peer-cert-file=/opt/ssl/etcd/etcd.pem --peer-key-file=/opt/ssl/etcd/etcd-key.pem --trusted-ca-file=/opt/ssl/k8sca/ca.pem --peer-trusted-ca-file=/opt/ssl/k8sca/ca.pem --initial-advertise-peer-urls=https://192.168.1.11:2380 --listen-peer-urls=https://192.168.1.11:2380 --listen-client-urls=https://192.168.1.11:2379,http://127.0.0.1:2379 --advertise-client-urls=https://192.168.1.11:2379 --initial-cluster-token=etcd-cluster-0 --initial-cluster etcd1=https://192.168.1.11:2380,etcd2=https://192.168.1.12:2380,etcd3=https://192.168.1.13:2380 --initial-cluster-state=new --data-dir=/var/lib/etcd Restart=on-failure RestartSec=5 LimitNOFILE=65536 [Install] WantedBy=multi-user.target 三、測試集群狀態(tài)
集群中所有主機配置均一致，僅IP地址不同。
$ etcdctl --ca-file=/opt/ssl/k8sca/ca.pem --cert-file=/opt/ssl/etcd/etcd.pem --key-file=/opt/ssl/etcd/etcd-key.pem cluster-health member aa869cb0f2e7ed31 is healthy: got healthy result from https://192.168.1.11:2379 member b08a644fd7247c5e is healthy: got healthy result from https://192.168.1.13:2379 member bb9bd2baaebf7d95 is healthy: got healthy result from https://192.168.1.12:2379 常見問題
- publish error: etcdserver: request timed out
我部署時先使用一臺進行測試，無論如何啟動etcd都無法啟動，提示publish error: etcdserver: request timed out。后來發(fā)現(xiàn)etcd.service中制定了其他etcd主機，所以當(dāng)單獨啟動一臺是連接其他主機不通，那么etcd就啟動失敗。所以要把etcd集群中所有主機都配置好，同時啟動就OK了。
