etcd节点扩容至两个节点

本篇已经安装了单个etcd，然后进行扩容etcd节点至2个，安装单节点请参照：https://www.cnblogs.com/effortsing/p/10295261.html

实验架构

test1: 192.168.0.91    etcd
test2: 192.168.0.92    etcd
test3: 192.168.0.93    无

需求：test1节点已经安装了etcd, 现在要把test2节点作为etcd节点添加进来

、环境配置

# 如下操作在所有节点操作

修改主机名

# 注意修改 各自节点对应的 主机名
sed -i '$a\hostname=test2' /etc/hostname
sed -i '$a\hostname=test2' /etc/sysconfig/network && hostnamectl set-hostname test2

配置hosts解析

cat >>/etc/hosts<<EOF
192.168.0.91 test1
192.168.0.92 test2
192.168.0.93 test3
EOF

禁用selinux

sed -i 's/SELINUX=permissive/SELINUX=disabled/' /etc/sysconfig/selinux

sed -i 's/enforcing/disabled/g' /etc/selinux/config

关闭swap

# 注释/etc/fstab文件里swap相关的行

sed -i 's/\/dev\/mapper\/centos-swap/#\/dev\/mapper\/centos-swap/g' /etc/fstab

关掉防火墙

systemctl stop firewalld && systemctl disable firewalld

都退出xshell查看主机名

开启forward

iptables -P FORWARD ACCEPT

配置转发相关参数
cat >> /etc/sysctl.d/k8s.conf <<EOF
net.bridge.bridge-nf-call-ip6tables =
net.bridge.bridge-nf-call-iptables =
vm.swappiness=
EOF

加载系统参数
sysctl --system

加载ipvs相关内核模块
如果重新开机，需要重新加载
modprobe ip_vs
modprobe ip_vs_rr
modprobe ip_vs_wrr
modprobe ip_vs_sh
modprobe nf_conntrack_ipv4
lsmod | grep ip_vs

安装etcd
useradd etcd
mkdir -p /server/software/k8s
mkdir -p /opt/k8s/bin
cd /server/software/k8s
wget https://github.com/coreos/etcd/releases/download/v3.2.18/etcd-v3.2.18-linux-amd64.tar.gz
tar -xf etcd-v3.2.18-linux-amd64.tar.gz
mv etcd-v3.2.18-linux-amd64/etcd* /opt/k8s/bin
chmod +x /opt/k8s/bin/*
ln -s /opt/k8s/bin/etcd /usr/bin/etcd
ln -s /opt/k8s/bin/etcdctl /usr/bin/etcdctl
etcd --version

2、复制test1单节点ca证书和私钥、etcd证书和私钥

test2 上先创建存放证书和私钥目录

mkdir -p /etc/kubernetes/cert/

mkdir -p /etc/etcd/cert/

从test1节点上找到证书复制过来

scp /etc/kubernetes/cert/ca*.pem root@192.168.0.92:/etc/kubernetes/cert/

scp /etc/etcd/cert/etcd*.pem root@192.168.0.92:/etc/etcd/cert/

  chmod 777 /etc/etcd/cert/*

  chmod 777 /etc/kubernetes/*

3、添加证书到linux系统受信任列表（选做）

添加根证书到linux系统受信任列表

cd /etc/kubernetes/cert/
cat ca.pem >> /etc/pki/tls/certs/ca-bundle.crt

添加etcd 证书到linux系统受信任列表

cd /etc/etcd/cert/
cat etcd.pem >> /etc/pki/tls/certs/ca-bundle.crt

5、添加新成员

5.1、注册新节点

# 在test1节点上操作

# etcdctl 在注册完新节点后，会返回一段提示，包含3个环境变量，需要在etcd启动脚本中修改成这3个环境变量
[root@test1 ~]# etcdctl --ca-file /root/ssl/ca.pem --cert-file /root/ssl/etcd.pem --key-file /root/ssl/etcd-key.pem member add test2 http://192.168.0.92:2380
Added member named test2 with ID 2eb21869c9f27e29 to cluster

ETCD_NAME="test2"
ETCD_INITIAL_CLUSTER="test2=http://192.168.0.92:2380,test1=https://192.168.0.91:2380"
ETCD_INITIAL_CLUSTER_STATE="existing"

5.2、修改test2节点的peer url为https
etcdctl --ca-file /etc/kubernetes/cert/ca.pem --cert-file /etc/etcd/cert/etcd.pem --key-file /etc/etcd/cert/etcd-key.pem member update test2 https://192.168.0.92:2380
如果执行失败，先跳过，不影响

6、 配置环境变量

# 在 test2 节点上操作

cat >> /etc/profile << EOF
export ETCD_NAME=$(hostname)
export INTERNAL_IP=$(hostname -i | awk '{print $NF}')
export ECTD_CLUSTER='test1=https://192.168.0.91:2380'
EOF
source /etc/profile

7、配置启动脚本

# 在 test2 节点操作

# 把第5 步 生成的结果写到 etcd启动脚本中，

mkdir -p /data/etcd

cat> /etc/systemd/system/etcd.service<< EOF
[Unit]
Description=Etcd Server
After=network.target
After=network-online.target
Wants=network-online.target
Documentation=https://github.com/coreos

[Service]
Type=notify
WorkingDirectory=/data/etcd
EnvironmentFile=-/etc/etcd/etcd.conf
ExecStart=/opt/k8s/bin/etcd \
--name ${ETCD_NAME} \
--cert-file=/etc/etcd/cert/etcd.pem \
--key-file=/etc/etcd/cert/etcd-key.pem \
--peer-cert-file=/etc/etcd/cert/etcd.pem \
--peer-key-file=/etc/etcd/cert/etcd-key.pem \
--trusted-ca-file=/etc/kubernetes/cert/ca.pem \
--peer-trusted-ca-file=/etc/kubernetes/cert/ca.pem \
--initial-advertise-peer-urls https://${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 my-etcd-token \
--initial-cluster $ECTD_CLUSTER,test2=http://192.168.0.92:2380 \
--initial-cluster-state existing \
--data-dir=/data/etcd
Restart=on-failure
RestartSec=5
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target
EOF

8、启动新节点

systemctl daemon-reload      #一定要执行，否则报错
systemctl start etcd
systemctl status etcd
systemctl enable etcd

9、查看集群成员和安全状态
# 在test1节点上操作
[root@test1 ~]# etcdctl --ca-file /etc/kubernetes/cert/ca.pem --cert-file /etc/etcd/cert/etcd.pem --key-file /etc/etcd/cert/etcd-key.pem member list
2eb21869c9f27e29: name=test2 peerURLs=http://192.168.0.92:2380 clientURLs=https://192.168.0.92:2379 isLeader=false
42f7141ed6110de1: name=test1 peerURLs=https://192.168.0.91:2380 clientURLs=https://192.168.0.91:2379 isLeader=true

[root@test1 ~]# etcdctl --ca-file /etc/kubernetes/cert/ca.pem --cert-file /etc/etcd/cert/etcd.pem --key-file /etc/etcd/cert/etcd-key.pem cluster-health
member 2eb21869c9f27e29 is healthy: got healthy result from https://192.168.0.92:2379
member 42f7141ed6110de1 is healthy: got healthy result from https://192.168.0.91:2379
cluster is healthy

9.2、修改所有节点启动文件一致，然后重启

报错解决：

[root@test2 k8s]# etcdctl --ca-file /etc/kubernetes/cert/ca.pem --cert-file /etc/etcd/cert/etcd.pem --key-file /etc/etcd/cert/etcd-key.pem member list
Error: client: etcd cluster is unavailable or misconfigured; error #0: dial tcp 127.0.0.1:4001: getsockopt: connection refused
; error #1: dial tcp 127.0.0.1:2379: getsockopt: connection refused

error #0: dial tcp 127.0.0.1:4001: getsockopt: connection refused
error #1: dial tcp 127.0.0.1:2379: getsockopt: connection refused

启动文件需要添加：
http://127.0.0.1:2379

其他报错，删除etcd数据目录重启