kuberntes 系統使用 etcd 存儲所有數據,是最重要的組件之一,註意 etcd集群只能有奇數個節點(1,3,5...),本文檔使用3個節點做集群。 一、基礎環境 軟體包 etcd下載地址: "https://github.com/coreos/etcd/releases" 伺服器 架構圖 ...
kuberntes 系統使用 etcd 存儲所有數據,是最重要的組件之一,註意 etcd集群只能有奇數個節點(1,3,5...),本文檔使用3個節點做集群。
一、基礎環境
軟體包
etcd下載地址:https://github.com/coreos/etcd/releases
伺服器
架構圖
二、生成etcd證書與私鑰
創建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
:定授權使用該證書的 etcd 節點 IP(應包含集群內所有節點的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證書在前面的章節創建 Kubernetes證書相關(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
創建etcd配置文件etcd.conf
,此配置文件是定義一些變數,方便etcd.service
文件中直接引用、方便後期維護。
配置文件的所有含義都在創建etcd.service配置文件後有詳解。
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"
創建etcd.service
配置文件
etcd.service
的變數都是引用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
:集群當中的其他節點
--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,用於通告集群其他成員
--listen-peer-urls
:用於監聽集群其他成員的URL列表
--listen-client-urls
:用於監聽客戶端通訊的URL列表
--advertise-client-urls
:通告客戶端的URL,用於列出所有客戶端
--initial-cluster-token
:etcd集群的初始集群令牌,伺服器必須通過令牌才能加入etcd集群
啟動etcd集群
集群所有節點都配置好配置文件,同時啟動。
systemctl daemon-reload && systemctl enable etcd && systemctl start etcd
不使用變數的配置方法
前面分別創建了/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
重定義的變數。
如若不想引用變數,可以不寫etcd.conf
。僅創建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
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
。後來發現etcd.service
中制定了其他etcd主機,所以當單獨啟動一臺是連接其他主機不通,那麼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。
參考
http://blog.51cto.com/sgk2011/2108542
https://github.com/gjmzj/kubeasz/blob/master/docs/setup/02-install_etcd.md
https://blog.csdn.net/qq_33199919/article/details/80623055
https://skyao.gitbooks.io/learning-etcd3/content/