数据库的热备归档+流复制模式配置
首先先做主备数据库之间的信任关系，使两台服务器之间互相访问不需要密码验证。
主服务器上 在root
postgresql 两个用户下分别生成证书
在主机A上执行如下命令来生成配对密钥：
ssh-keygen -t rsa
按照提示操作，注意，不要输入passphrase。提示信息如下
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /root/.ssh/id_rsa.
Your public key has been saved in /root/.ssh/id_rsa.pub.
The key fingerprint is:
ff:8e:85:68:85:94:7c:2c:46:b1:e5:2d:41:5c:e8:9b [email protected]
将 .ssh 目录中的 id_rsa.pub 文件复制到 主机B 的 ~/.ssh/ 目录中，并改名为 authorized_keys。
scp .ssh/id_rsa.pub 192.168.2.91:/root/.ssh/authorized_keys
备注：scp id_rsa.pub [email protected]:/home/postgres/.ssh/authorized_keys
以后从A主机scp到B主机就不需要密码了。
使用上面的操作，反过来再建立B连接A不需要密码验证，方法是把B的公钥id_rsa.pub 改名放到A的.ssh目录下。
如果用户名不相同，需要把访问者用户的公钥放到被访问者服务器用户目录下的.ssh目录，并把公钥id_rsa.pub的内容添加到
authorized_keys 用户中。
cat id_rsa.pub >> 目录/authorized_keys
主库操作：
修改：vim /usr/local/pgsql/data/pg_hba.conf
添加：
local all all trust
host all all 127.0.0.1/32 trust
# IPv6 local connections:
host all all 192.168.2.0/24 trust
# Allow replication connections from localhost, by a user with the
# replication privilege.
host replication postgres 192.168.2.0/24 trust
host replication postgres ::1/128 trust
编辑vim /usr/local/pgsql/data/postgresql.conf
max_wal_senders = 5
wal_keep_segments = 1000
wal_sender_timeout = 60s
hot_standby = on
log_destination = 'stderr'
logging_collector = on
log_directory = 'pg_log'
log_filename = 'postgresql-%Y-%m-%d_%H%M%S.log'
log_file_mode = 0600
log_rotation_age = 1d
log_rotation_size = 20MB
client_min_messages = notice
log_min_messages = warning
log_min_error_statement = error
log_min_duration_statement = 60
shared_preload_libraries = 'pg_stat_statements'
pg_stat_statements.max = 1000
pg_stat_statements.track = top
pg_stat_statements.track_utility = true
pg_stat_statements.save = true
log_checkpoints = on
log_connections = on
log_lock_waits = on
log_statement = 'ddl'
log_timezone = 'PRC'
在/data目录下创建存放归档日志的目录
mkdir archivedir
chown postgres.postgres archivedir
创建存储数据库基础备份的目录/data
mkidr pgbackup
chown postgres.postgres pgbackup
以上操作完毕后，重启postgresql数据库。
/etc/init.d/postgresql restart
/usr/local/pgsql/bin/pg_ctl restart -D /usr/local/pgsql/data/
创建数据库基础本分：
进入postgresql 用户：
su -l postgres
[postgres@AY131021150028549089Z ~]$ psql
postgres=# SELECT pg_start_backup('basebak20151209');
pg_start_backup
-----------------
0/8000028
(1 row)
postgres=# \q
[postgres@AY131021150028549089Z ~]$ exit
[root@AY131021150028549089Z data]# cd pgbackup/
[root@AY131021150028549089Z pgbackup]# tar zvcf base201510_data.tar.gz /data 复制数据库数据目录并压缩成文件
[root@AY131021150028549089Z data]# su -l postgres
[postgres@AY131021150028549089Z ~]$ psql
postgres=# SELECT pg_stop_backup();
NOTICE: pg_stop_backup complete, all required WAL segments have been archived
pg_stop_backup
----------------
0/8000230
(1 row)
postgres=# \q
[root@AY131021150028549089Z data]# cd pgbackup/
[root@AY131021150028549089Z pgbackup]# chown postgres.postgres base20131112_data.tar.gz
备库上的操作：
在/data下创建 pgbackup目录
mkdir archivedir
chown postgres.postgres archivedir
创建存储数据库基础备份的目录
mkdir pgbackup
chown postgres.postgres pgbackup
以上操作完毕后，停止postgresql数据库。
/etc/init.d/postgresql stop 停止当前备用数据库的运行
su
su -l postgres
cd /data/pgbackup
scp 192.168.2.91:/data/pgbackup/base20131112_data.tar.gz ./ 复制主库的基本库备份文件
[postgres@AY131021150027813b05Z pgbackup]$ tar zvxf base20131112_data.tar.gz -C ../ 解压缩并复制到备库数据目录中去
cd /data/data/pg_xlog
[postgres@AY131021150027813b05Z pg_xlog]$ rm -f 0*
[postgres@AY131021150027813b05Z archive_status]$ rm -f 0*
cd /data/data
rm postmaster.pid
cp /usr/local/pgsql/share/recovery.conf.sample ./recovery.conf
编辑recover.conf文件
restore_command = 'scp 10.161.166.25:/data/archivedir/%f "%p" 2> /dev/null'
recovery_target_timeline = 'latest'
standby_mode = 'on'
primary_conninfo = 'host=172.31.2.150 port=5432 user=postgres'
trigger_file = '/tmp/trigger_file0'
chown postgres.postgres recovery.conf权限
修改完成后，重启数据库
/etc/rc.d/init.d/postgres start