postgresql 12版本搭建及主备部署

postgresql 12版本主备部署

环境搭建

centos 7+
postgresql 12.0

# 网络检查
ping -c2 baidu.com

#关闭防火墙，selinux
systemctl stop firewalld && sudo systemctl disable firewalld
sed -ri s/SELINUX=enforcing/SELINUX=disabled/g /etc/selinux/config
setenforce 0

### 配置阿里云yum源

mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.bak
curl -o /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo

#echo "isntalling tools"
yum -y install vim net-tools wget ntpdate
yum -y groupinstall "Development Tools"

# 时间同步
echo "*/10 * * * * /usr/sbin/ntpdate ntp.aliyun.com > /dev/null 2>&1" >>/etc/crontab

# 加快ssh连接
sed -ri s/"#UseDNS yes"/"UseDNS no"/g /etc/ssh/sshd_config
systemctl restart sshd

## 环境准备，根据自身需要，减少或者增加
yum install -y wget gcc gcc-c++  epel-release llvm5.0 llvm5.0-devel clang libicu-devel perl-ExtUtils-Embed readline readline-devel zlib zlib-devel openssl openssl-devel pam-devel libxml2-devel libxslt-devel openldap-devel systemd-devel tcl-devel python-devel

## 下载、解压，安装
cd /usr/local/src
wget https://ftp.postgresql.org/pub/source/v12.0/postgresql-12.0.tar.gz
tar -xvzf postgresql-12.tar.gz
cd postgresql-12
./configure --prefix=/usr/local/pgsql/12 --enable-nls --with-python --with-tcl --with-gssapi --with-icu --with-openssl --with-pam --with-ldap --with-systemd --with-libxml --with-libxslt
make && make install

## 创建目录和用户,以及配置环境变量

groupadd postgres
useradd -g postgres postgres
## 密码设置在引号内输入自己的密码
echo "postgres" | passwd --stdin postgres

mkdir -p /data/pgdata/{data,archivedir}
chown -R postgres:postgres /usr/local/pgsql -R
chown postgres:postgres /data/pgdata -R

echo "export PATH=/usr/local/pgsql/12/bin:$PATH" >/etc/profile.d/pgsql.sh
source /etc/profile.d/pgsql.sh

环境部署已经完成,接下来我们来搭建postgresql的主备

主备搭建

备库搭建

以下的操作均在postgres用户下进行

su - postgres
##初始化
initdb -D /data/pgdata/data -U postgres --locale=en_US.UTF8 -E UTF8
cp /data/pgdata/data/{pg_hba.conf,pg_hba.conf.bak}
## 允许repl用户进行流复制
cat <<-eof >>/data/pgdata/data/pg_hba.conf
host    all             all             0.0.0.0/0               md5
host    replication     repl            192.168.0.0/22            trust
eof

cp /data/pgdata/data/{postgresql.conf,postgresql.conf.bak}
##配置postgresql.conf
cat <<-eof >/data/pgdata/data/postgresql.conf
listen_addresses = '*'                     
port = 5432
max_connections = 100
superuser_reserved_connections = 10
full_page_writes = on
wal_log_hints = off
max_wal_senders = 50
hot_standby = on
log_destination = 'csvlog'
logging_collector = on
log_directory = 'log'
log_filename = 'postgresql-%Y-%m-%d_%H%M%S'
log_rotation_age = 1d
log_rotation_size = 10MB
log_statement = 'mod'
log_timezone = 'PRC'
timezone = 'PRC'
unix_socket_directories = '/tmp'
shared_buffers = 512MB
temp_buffers = 16MB
work_mem = 32MB
effective_cache_size = 2GB
maintenance_work_mem = 128MB
#max_stack_depth = 2MB
dynamic_shared_memory_type = posix
## PITR
full_page_writes = on
wal_buffers = 16MB
wal_writer_delay = 200ms
commit_delay = 0
commit_siblings = 5
wal_level = replica
archive_mode = on
archive_command = 'test ! -f /data/pgdata/archivedir/%f && cp %p /data/pgdata/archivedir/%f'
archive_timeout = 60s
eof
## 启动数据库
pg_ctl -D /data/pgdata/data -l /data/pgdata/data/serverlog start
## 创建用户进行流复制连接
psql -U postgres -c "ALTER USER postgres WITH PASSWORD 'postgres';"
psql -U postgres -c "CREATE USER  repl WITH PASSWORD 'postgres' REPLICATION;"

备库搭建

## 备份复制，备库配置，
pg_basebackup -h 192.168.3.62 -p 5432 -U repl -w -Fp -Xs -Pv -R -D /data/pgdata/data


根据主库的postgresql.conf 配置文件 修改参数配置:
1, listen_addresses = '* '
2, wal_level = hot_standby
3, max_connections = xxx, # 一般比主库大一些.
4,hot_standby = on
5, max_standby_streaming_delay = 30s
6. wal_receiver_status_interval = 10s
7, hot_standby_feedback = on # 如果有错误的数据复制,是否向 主进行范例.

### 在postgre.auto.conf 添加 application_name =slave1,配置如下
primary_conninfo = 'application_name=slave1 user=repl passfile=''/home/postgres/.pgpass'' host=192.168.3.62 port=5432 sslmode=prefer sslcompression=0 gssencmode=prefer krbsrvname=postgres target_session_attrs=any'

## 启动备库
pg_ctl -D /data/pgdata/data start

写在最后（状态检查）

##状态检查
### 回到主库查看状态
$ psql  -c "select client_addr,usename,backend_start,application_name,sync_state,sync_priority FROM pg_stat_replication;"
 client_addr  | usename |         backend_start         | application_name | sync_state | sync_priority 
--------------+---------+-------------------------------+------------------+------------+---------------
 192.168.3.61 | repl    | 2019-10-16 15:34:45.130732+08 | slave1           | async      |             0
(1 row)

$ psql  -c "select client_addr, sync_state from pg_stat_replication;"
 client_addr  | sync_state 
--------------+------------
 192.168.3.61 | async
(1 row)

##备库只读, 所以任何操作, 都会告警失败:
postgres=# drop database pgtest;
ERROR:  cannot execute DROP DATABASE in a read-only transaction

## 查看主备的状态
#主
ps -ef  |grep sender
postgres  92996  51692  0 15:34 ?        00:00:00 postgres: walsender repl 192.168.3.61(53958) streaming 0/8000060
postgres 101845  20470  0 15:45 pts/2    00:00:00 grep --color=auto sender

#备
ps -ef  |grep recover
postgres  98311  98309  0 15:34 ?        00:00:00 postgres: startup   recovering 000000010000000000000008
postgres 108029  21054  0 15:46 pts/2    00:00:00 grep --color=auto recover

#通过此命令判断主备
pg_controldata -D /data/pgdata/data/ |grep state

in archive recovery ## 表示从库
in production       ## 表示主库

最后，希望大家多多指正，相互学习；如遇见问题，我们可以讨论，相互学习。