下载地址：http://pgpool.net/mediawiki/index.php/Downloads
环境：
两台redhat linux 6.5 两台机器上均安装好pg（本机postgresql9.4.4）
ip：data1 192.168.11.66 （主） pgpool安装在此机器上
data2 192.168.11.68 （备）
1、源码安装
[root@localhost ~]# tar xvf pgpool-II-3.3.3.tar.gz
[root@localhost ~]#mkdir /opt/pgpool
[root@localhost ~]#chown -R postgres:postgres /opt/*
[postgres@localhost~]$ cd /opt/pgpool-II-3.3.3
[postgres@localhost pgpool-II-3.3.3]$./configure --prefix=/opt/pgpool
[postgres@localhost pgpool-II-3.3.3]$make
[postgres@localhost pgpool-II-3.3.3]$make install2、安装pgpool_regclass 和pgpool-recovery
[postgres@localhost pgpool-II-3.3.3]$ cd /pgpool-II-3.3.3/sql/pgpool_regclass
[postgres@localhost pgpool_regclass]$make && make install
[postgres@localhost pgpool_regclass]$psql -f pgpool-regclass.sql template1
[postgres@localhost pgpool_regclass]$cd /pgpool-II-3.3.3/sql/pgpool-recovery
[postgres@localhost pgpool-recovery] $make && make install
[postgres@localhost pgpool-recovery]$psql -f pgpool-recovery.sql template1
3、建立inert_lock表
[postgres@localhost pgpool-recovery]$cd /pgpool-II-3.3.3/sql/
[postgres@localhost sql]$psql -f insert_lock.sql template14、配置即使用
查看配置文件
[postgres@localhost pgpool-II-3.3.3]$ cd /opt/pgpool/etc/
[postgres@localhost etc]$ ll
total 180
-rw-r--r--. 1 postgres postgres 858 Dec 19 13:28 pcp.conf.sample
-rw-r--r--. 1 postgres postgres 30979 Dec 19 13:28 pgpool.conf.sample
-rw-r--r--. 1 postgres postgres 30669 Dec 19 13:28 pgpool.conf.sample-master-slave
-rw-r--r--. 1 postgres postgres 30651 Dec 19 13:28 pgpool.conf.sample-replication
-rw-r--r--. 1 postgres postgres 30690 Dec 19 13:28 pgpool.conf.sample-stream
-rw-r--r--. 1 postgres postgres 3200 Dec 19 13:28 pool_hba.conf.sample
-rw-rw-r--. 1 postgres postgres 43 Dec 19 13:53 pool_passwd
[postgres@localhost etc]$ cp pgpool.conf.sample pgpool.conf
[postgres@localhost etc]$ cp pcp.conf.sample pcp.conf
[postgres@localhost etc]$ pool_hba.conf.sample pool_hba.conf
pg_pool默认只接受端口的本地连接。如果想从其他主机接受连接，请设置listen_address='*' ,相对应在pgpool.conf中配置修改如下：
listen_address='*'
port =9999
因为不是安装在默认的“/usr/local/”目录下的，所以要指定目录的配置项，
pid_file_name ='/opt/pgpool/run/pgpool.pid'
创建相对应目录的命令
[postgres@localhost etc]$mkdir /opt/pgpool/run
配置后端数据库，pgpool.conf
# - Backend Connection Settings - 这一部分用来配置后台连接的数据库
backend_hostname0 = '192.168.11.66'
backend_port0 = 5432
backend_weight0 = 1
backend_data_directory0 = '/opt/pgsql/data'
backend_flag0 = 'ALLOW_TO_FAILOVER'
backend_hostname1 = '192.168.11.68'
backend_port1 = 5432
backend_weight1 = 1
backend_data_directory1 = '/opt/pgsql/data'
backend_flag1 = 'ALLOW_TO_FAILOVER'
一般使用hba的方式进行登录认证。所以要在pgpool.conf中打开如下选项：
enable_pool_nba=on
通常会把访问pgpool的用户名和密码的MD5值记录在/opt/pgpool/etc/pool_passwd中
[postgres@localhost etc]$pg_md5 -m -p -u postgres pool_passwd
passwd:
这样就生成了pool_passwd文件，使用cat查看文件内容：
postgres:md5279d84d3239474da07235e5a6555c73b
启动pgpool
[postgres@localhost etc]$pgpool
如果想让pgpool在前台运行，可以加“-n”参数
[postgres@localhost etc]$pgpool -n
如果想让日志打印到一个文件。使用一下命令
[postgres@localhost etc]$pgpool -n> /tmp/pgpool.log 2>&1 &
如果想打印调度信息，加上参数“-d”
[postgres@localhost etc]$pgpool -n -d > /tmp/pgpool.log 2>&1 &
停止pgpool
[postgres@localhost etc]$pgpool stop
也可以加上参数
[postgres@localhost etc]$pgpool -m fast stop5、复制和负载均衡的示例
在pgpool.conf中配置以下内容：
replication_mode = true
load_balance_mode = truebackend_hostname0 = '192.168.11.66'
backend_port0 = 5432
backend_weight0 = 1
backend_data_directory0 = '/opt/pgsql/data'
backend_flag0 = 'ALLOW_TO_FAILOVER'
backend_hostname1 = '192.168.11.68'
backend_port1 = 5432
backend_weight1 = 1
backend_data_directory1 = '/opt/pgsql/data'
backend_flag1 = 'ALLOW_TO_FAILOVER'启动pgpool
pgpool -f /opt/pgpool/etc/pgpool.conf在data1上连接pgpool的端口9999，然后创建一张表。并插入数据
[postgres@localhost etc]$ psql -h 192.168.11.66 -d postgres -p 9999 -U postgres
psql (9.4.4)
Type "help" for help.postgres=# \d
List of relations
Schema | Name | Type | Owner
----------------+------+------+--------
oracle_catalog | dual | view | postgres
(1 row)postgres=# create table aaa (a int);
CREATE TABLE
highgo=# \d
List of relations
Schema | Name | Type | Owner
----------------+------+-------+--------
oracle_catalog | dual | view | postgres
public | aaa | table | postgres
(2 rows)postgres=# insert into aaa values (1);
INSERT 0 1
postgres=# insert into aaa values (2);
INSERT 0 1
postgres=# insert into aaa values (3);
INSERT 0 1
postgres=# select * from aaa ;
a
---
1
2
3
(3 rows)
在data2上可以看到，表和数据都弄好了，而且数据完全一样
[postgres@localhost data]$ psql
Password:
psql (9.4.4)
Type "help" for help.postgres=# \d
List of relations
Schema | Name | Type | Owner
----------------+------+-------+--------
oracle_catalog | dual | view | postgres
public | aaa | table | postgres
(2 rows)postgres=# select * from aaa ;
a
---
1
2
3
(3 rows)