Postgresql数据库高可用-patroni+etcd+haproxy

一、patroni的部署

当前架构图

1. 安装PG流复制集群1master2slave

参考： PostgreSQL-流复制集群搭建_pg流复制集群-优快云博客

2. Ubuntu制作patroni沙箱

在一台有外网的Ubuntu机器上制作沙箱

• 安装虚拟环境virtualenv

cd /data/apps/
pip3 install virtualenv -i  https://pypi.tuna.tsinghua.edu.cn/simple
virtualenv -p /usr/bin/python3 patroni-4.0.4
# 进入虚拟环境
source /data/apps/patroni-4.0.4/bin/activate

• vim requirements.txt

urllib3>=1.19.1,!=1.21
boto3
PyYAML
kazoo>=1.3.1
python-etcd>=0.4.3,<0.5
py-consul>=1.1.1
click>=4.1
prettytable>=0.7
python-dateutil
pysyncobj>=0.3.8
cryptography>=1.4
psutil>=2.0.0
ydiff>=1.2.0,<1.5,!=1.4.0,!=1.4.1
python-json-logger>=2.0.2
psycopg2-binary
patroni[etcd]

• 将沙箱patroni-4.0.4打包

tar-zcvf patroni-4.0.4.tar.gz patroni-4.0.4

• 后续传到pg服务器上的/data/apps/目录下（必须是/data/apps/目录）

3. 安装etcd

• 下载etcd安装包

略

• 编辑配置文件（3台机器）

# This is the configuration file for the etcd server.

# Human-readable name for this member.
name: 'etcd-1'    # 3台机器不相同

# Path to the data directory.
data-dir: /data/etcd1

# List of comma separated URLs to listen on for peer traffic.
listen-peer-urls: http://10.50.18.33:2380    # 改成本机IP

# List of comma separated URLs to listen on for client traffic.
listen-client-urls: http://10.50.18.33:2379    # 改成本机IP

# List of this member's peer URLs to advertise to the rest of the cluster.
# The URLs needed to be a comma-separated list.
initial-advertise-peer-urls: http://10.50.18.33:2380    # 改成本机IP

# List of this member's client URLs to advertise to the public.
# The URLs needed to be a comma-separated list.   
advertise-client-urls: http://10.50.18.33:2379      # 改成本机IP

# Comma separated string of initial cluster configuration for bootstrapping.
# Example: initial-cluster: "infra0=http://10.0.1.10:2380,infra1=http://10.0.1.11:2380,infra2=http://10.0.1.12:2380"
initial-cluster: "etcd-1=http://10.50.18.33:2380,etcd-2=http://10.50.18.235:2380,etcd-3=http://10.50.18.222:2380"

# Initial cluster token for the etcd cluster during bootstrap.
initial-cluster-token: 'etcd-cluster-token-1'

# Initial cluster state ('new' or 'existing').
initial-cluster-state: 'new'

• 编辑启动文件（3台机器）

[Unit]
Description="etcd"
Requires=network-online.target
After=network-online.target

[Service]
User=root
Group=root
ExecStart=/usr/local/bin/etcd --config-file=/etc/etcd/etcd.yml
ExecReload=/bin/kill --signal HUP $MAINPID
KillMode=process
KillSignal=SIGTERM
Restart=on-failure
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target

• 3台机器启动etcd

systemctl daemon-reload
systemctl start etcd
systemctl enable etcd

4. 安装patroni

• 将上面的沙箱拷贝到/data/apps/下

#解压沙箱
cd /data/apps/
tar xvf patroni-4.0.4.tar.gz

#修改目录权限
chown -R postgres. /data/apps/patroni-4.0.4

• 编辑配置文件（3台机器）

#vim patroni.yml
scope: pg_cluster
namespace: /pg_cluster/
name: k8s-worker-1.ai.ksyun.com    # 3台机器不一致，写主机名就行

restapi:
  listen: 0.0.0.0:8008
  connect_address: 10.50.18.33:8008    # 改成本机IP

# etcd地址填对了
etcd3:
  #Provide host to do the initial discovery of the cluster topology:
  hosts: 
    - 10.50.18.33:2379
    - 10.50.18.235:2379
    - 10.50.18.222:2379
  etcd3: true 

bootstrap:
  # this section will be written into Etcd:/<namespace>/<scope>/config after initializing new cluster
  # and all other cluster members will use it as a `global configuration`
  dcs:
    ttl: 30
    loop_wait: 10
    retry_timeout: 6000
    maximum_lag_on_failover: 1048576
    master_start_timeout: 300
    synchronous_mode: true
    postgresql:
      # 下面的配置是在原有配置的基础上新增了一条patroni用户，就这么写不用管
      pg_hba:
      - local   all             all                                     trust
      - host    all             all             127.0.0.1/32            trust
      - host    all             all             ::1/128                 trust
      - local   replication     all                                     trust
      - host    replication     all             127.0.0.1/32            trust
      - host    replication     all             ::1/128                 trust
      - h