22.11:/opt/ppas_arch/%f"%p"'
[root@ppas2 ~]# chown enterprisedb.enterprisedb /opt/PostgresPlus/
9.0AS/data/recovery.conf[root@ppas2 ~]# /etc/init.d/ppas-9.0 start
13
两台服务器的Stream Replication 已经完成
＃＃＃＃＃＃＃＃＃＃＃＃＃＃＃＃＃＃＃＃＃＃＃＃＃＃＃＃
下面的留着当备注
14
[root@ppas1 ~]# mkdir /var/run/pgpool
15
[root@ppas1 ~]# cp /opt/PostgresPlus/9.0AS/etc/pgpool.conf.samplestream /opt/PostgresPlus/9.0AS/etc/pgpool.conf
[root@ppas1 ~]# vim /opt/PostgresPlus/9.0AS/etc/pgpool.conf
修改：
backend_hostname0 = '192.168.122.11'
backend_port0 = 5444
backend_weight0 = 1
backend_data_directory0 = '/opt/PostgresPlus/9.0AS/data'
backend_hostname1 = '192.168.122.12'
backend_port1 = 5444
backend_weight1 = 1
backend_data_directory1 = '/opt/PostgresPlus/9.0AS/data'
16
[root@ppas1 ~]# edb-psql -U enterprisedb edb -c "select md5('1q2w3e4r');"
md5
---------------------------------
5416d7cd6ef195a0f7622a9c56b55e84
(1 row)
[root@ppas1 ~]# echo "enterprisedb:5416d7cd6ef195a0f7622a9c56b55e84" >> /opt/PostgresPlus/9.0AS/etc/pcp.conf
17
启动PGPool
[root@ppas1 ~]# /opt/PostgresPlus/9.0AS/bin/pgpool -f /opt/PostgresPlus/9.0AS/etc/pgpool.conf -F /opt/PostgresPlus/9.0AS/etc/
pcp.conf
[root@ppas1 ~]# netstat -natulp | grep 9999
tcp 0 0 127.0.0.1:9999 0.0.0.0:* LISTEN 2434/pgpool
[root@ppas1 ~]#
18
[root@ppas1 ~]# edb-psql -p 9999 -U enterprisedb edbedb-psql (9.0.4.10)
Type "help" for help.
edb=# create table a (id int);
CREATE TABLE
edb=# insert into a values (5),(6);
INSERT 0 2
edb=# select * from a;
id
---
5
6
(2 rows)
19
[root@ppas1 ~]# /etc/init.d/ppas-9.0 stopStopping Postgres Plus Advanced Server 9.0:
waiting for server to shut down....... doneserver stopped
20
[root@ppas2 ~]# edb-psql -h 192.168.122.11 -p 9999 -U enterprisedbedb
edb-psql: server closed the connection unexpectedlyThis probably means the server terminated abnormallybefore or while processing the request.
以上连接出错是由于pgpool 正好此时的路由指向到PPAS1，但此时PPAS1的
数据库已经STOP 。
[root@ppas2 ~]# edb-psql -h 192.168.122.11 -p 9999 -U enterprisedbedb
edb-psql (9.0.4.10)
Type "help" for help.
edb=#
重新再连接一次，此时pgpool 会将连接转向PPAS2，同时在pgpool 内部会将PPAS1定为故障状态，直到PPAS1的数据库重新可用。
21
edb=# insert into a values (7);
ERROR: cannot execute INSERT in a read-only transaction
由于PPAS2还在Stream Replication 的Slave 状态，因此不可做写数据操作
edb=# \q
22
[root@ppas2 ~]# touch /opt/PostgresPlus/9.0AS/data/recovery_trigger
[root@ppas2 ~]# edb-psql -h 192.168.122.11 -p 9999 -U enterprisedbedb
edb-psql (9.0.4.10)
Type "help" for help.
edb=# insert into a values (7);
ERROR: cannot execute INSERT in a read-only transaction
此处操作太快了，因此
系统还没有改为Master 状态
edb=# insert into a values (7);
INSERT 0 1
再过1-2 秒进行操作，写入成功
edb=#
-----------------
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blog.csdn.net/beiigang