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Docker快速搭建PostgreSQL15流复制集群

article 2024/9/30 21:28:49

搭建流复制集群

获取镜像

拉取镜像：docker pull timescale/timescaledb-ha:pg15-all

配置 docker-compose.yaml 文件：

version: '3.9'
services:
  # 写节点
  postgres-01:
    container_name: postgres-01
    hostname: postgres-01
    image: timescale/timescaledb-ha:pg15-all
    privileged: true
    environment:
      POSTGRES_USER: postgres
      POSTGRES_PASSWORD: postgres
      POSTGRES_DB: postgres
    volumes:
      - ./postgres-01:/home/postgres
    ports:
      - "5001:5432"
    networks:
      pg-net:
        ipv4_address: 10.20.0.5
  # 读节点一      
  postgres-02:
    container_name: postgres-02
    hostname: postgres-02
    image: timescale/timescaledb-ha:pg15-all
    privileged: true
    environment:
      PGDATA: /home/postgres/db
      POSTGRES_USER: postgres
      POSTGRES_PASSWORD: postgres
      POSTGRES_DB: postgres
    volumes:
      - ./postgres-02:/home/postgres
    ports:
      - "5002:5432"
    networks:
      pg-net:
        ipv4_address: 10.20.0.6
  # 读节点二      
  postgres-03:
    container_name: postgres-03
    hostname: postgres-03
    image: timescale/timescaledb-ha:pg15-all
    privileged: true
    environment:
      PGDATA: /home/postgres/db
      POSTGRES_USER: postgres
      POSTGRES_PASSWORD: postgres
      POSTGRES_DB: postgres
    volumes:
      - ./postgres-03:/home/postgres
    ports:
      - "5003:5432"
    networks:
      pg-net:
        ipv4_address: 10.20.0.7
networks:
  pg-net:
    ipam:
      config:
        - subnet: 10.20.0.0/16

目录结构如下：

➜  postgres ✗ ls -lh                             
total 8
-rw-r--r--@ 1 yuelong  staff   1.3K Sep 23 17:03 docker-compose.yaml
drwxr-xr-x@ 4 yuelong  staff   128B Sep 23 14:34 postgres-01
drwxr-xr-x@ 5 yuelong  staff   160B Sep 23 14:52 postgres-02
drwxr-xr-x@ 3 yuelong  staff    96B Sep 23 14:06 postgres-03

这里最好将 postgres-01、postgres-02和 postgres-03 设置为：chmod 777 -R postgres-01。接着启动容器：docker compose up -d。

主节点配置

进入主节点的容器内：docker exec -it postgres-01 sh

如果需要 root 的权限可以执行：docker exec -it -u root postgres-01 sh

进入容器内的/home/postgres/pgdata/data目录，修改 pg_hba.conf：

# TYPE  DATABASE        USER            ADDRESS                 METHOD

# "local" is for Unix domain socket connections only
local   all             all                                     trust
# IPv4 local connections:
host    all             all             127.0.0.1/32            trust
# IPv6 local connections:
host    all             all             ::1/128                 trust
# Allow replication connections from localhost, by a user with the
# replication privilege.
local   replication     all                                     trust
host    replication     all             127.0.0.1/32            trust
host    replication     all             ::1/128                 trust
# 配置允许复制客户端
host    replication     all             0.0.0.0/0               md5
host    all             all             all                     scram-sha-256

接着配置 postgresql.conf：

#设置以下
listen_addresses = '*' # 允许远程连接
hot_standby = on # 打开热备
wal_level = replica     # 设置 WAL 日志级别为 replica
max_wal_senders = 3     # 允许的 WAL 发送者数量，根据需要进行调整

接着退出容器，重启容器：docker compose restart postgres-01。

然后在进入容器内，进入 psql，创建流复制的账号：

$ psql
psql (15.8 (Ubuntu 15.8-1.pgdg22.04+1))
Type "help" for help.

postgres=# create role replica with login replication encrypted password 'replica';
create role

好了，这样主节点就配置好了。

从节点配置

接下来配置从节点，这里我们先设置数据目录为：

version: '3.9'
services:
  # 写节点
  ......
  # 读节点一      
  postgres-02:
    container_name: postgres-02
    hostname: postgres-02
    image: timescale/timescaledb-ha:pg15-all
    privileged: true
    environment:
      # 配置数据目录
      PGDATA: /home/postgres/db
      POSTGRES_USER: postgres
      POSTGRES_PASSWORD: postgres
      POSTGRES_DB: postgres
    volumes:
      - ./postgres-02:/home/postgres

这个时候我们需要进入 postgres-02 的容器内：docker exec -it postgres-02 sh，同步主节点的数据。

pg_basebackup -Fp --progress -D /home/postgres/pgdata/data -R -h 10.20.0.5 -p 5432 -U replica --password

这里的/home/postgres/pgdata/data是默认数据目录，回车输入 replica 的密码。

Password: 
28692/28692 kB (100%), 1/1 tablespace

同步完成之后在/home/postgres/pgdata/data中会出现主节点的数据，这里需要注意postgresql.auto.conf和standby.signal。这里的postgresql.auto.conf会记录主节点的信息：

$ cat postgresql.auto.conf
# Do not edit this file manually!
# It will be overwritten by the ALTER SYSTEM command.
primary_conninfo = 'user=replica password=replica channel_binding=prefer host=10.20.0.5 port=5432 sslmode=prefer sslcompression=0 sslcertmode=allow sslsni=1 ssl_min_protocol_version=TLSv1.2 gssencmode=prefer krbsrvname=postgres gssdelegation=0 target_session_attrs=any load_balance_hosts=disable'

接着退出容器，修改 docker-compose.yaml的 postgres-02容器的数据目录注释掉：

version: '3.9'
services:
  # 写节点
  ......
  # 读节点一      
  postgres-02:
    container_name: postgres-02
    hostname: postgres-02
    image: timescale/timescaledb-ha:pg15-all
    privileged: true
    environment:
      # 配置数据目录
      #PGDATA: /home/postgres/db
      POSTGRES_USER: postgres
      POSTGRES_PASSWORD: postgres
      POSTGRES_DB: postgres
    volumes:
      - ./postgres-02:/home/postgres

然后删除掉 postgres-02容器，重启启动：

docker compose down postgres-02
docekr compose up -d postgres-02

另一个节点也是一样操作。

测试

在主节点的 psql 中执行：SELECT * FROM pg_stat_replication;

postgres=# SELECT * FROM pg_stat_replication;
 pid | usesysid | usename | application_name | client_addr  | client_hostname | client_port |         backend_start         | backend_xmin |   state   | sent_lsn  | write_lsn | flush_lsn | replay_lsn | write_lag | flush_lag | replay_lag | sync_priority | sync_state |          reply_time           
-----+----------+---------+------------------+--------------+-----------------+-------------+-------------------------------+--------------+-----------+-----------+-----------+-----------+------------+-----------+-----------+------------+---------------+------------+-------------------------------
 400 |    20845 | replica | walreceiver      | 10.20.0.6 |                 |       58166 | 2024-09-23 10:36:09.844301+00 |              | streaming | 0/7018420 | 0/7018420 | 0/7018420 | 0/7018420  |           |           |            |             0 | async      | 2024-09-23 11:57:15.271431+00
 469 |    20845 | replica | walreceiver      | 10.20.0.7 |                 |       42680 | 2024-09-23 10:41:39.307304+00 |              | streaming | 0/7018420 | 0/7018420 | 0/7018420 | 0/7018420  |           |           |            |             0 | async      | 2024-09-23 11:57:15.29262+00
(2 rows)

这就配置成功了。

开始插件

我们这里使用的timescale/timescaledb-ha:pg15-all镜像里面包含了，时序和空间插件，这里连接是数据库，执行SELECT * FROM pg_extension;查看开启的插件。

postgres=# SELECT * FROM pg_extension;
  oid  |       extname       | extowner | extnamespace | extrelocatable | extversion |                                                                                 extconfig                                                                                 |                                                              extcondition                                                               
-------+---------------------+----------+--------------+----------------+------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------+-----------------------------------------------------------------------------------------------------------------------------------------
 13542 | plpgsql             |       10 |           11 | f              | 1.0        |                                                                                                                                                                           | 
 17830 | timescaledb_toolkit |       10 |         2200 | f              | 1.18.0     |                                                                                                                                                                           | 
 16384 | timescaledb         |       10 |         2200 | f              | 2.16.1     | {16403,16404,16426,16440,16439,16459,16458,16474,16473,16499,16515,16516,16533,16532,16552,16553,16609,16622,16649,16662,16672,16682,16686,16702,16712,16727,16736,16735} | {"","WHERE id >= 1","","","","","","","","","","","","","","WHERE id >= 1000"," WHERE key <> 'uuid' ","","","","","","","","","","",""}
(3 rows)

这里需要我们先创建一个数据库：

create database db1; # 创建库
\c db1;    # 连接库
CREATE EXTENSION postgis;  # 开启插件
CREATE EXTENSION postgis_topology; 
CREATE EXTENSION fuzzystrmatch; 
CREATE EXTENSION postgis_tiger_geocoder;