postgresql从9.0开始有流复制，这里记录一下流复制的安装记录。
环境：
redhat 5.5 64位
PG版本：9.1.2
master：192.168.1.168
slave:192.168.1.169
1.配置主机系统相关参数
1.1修改/etc/sysctl.conf
kernel.shmmni = 4096
kernel.sem = 50100 64128000 50100 1280
fs.file-max = 7672460
net.ipv4.ip_local_port_range = 9000 65000
net.core.rmem_default = 1048576
net.core.rmem_max = 4194304
net.core.wmem_default = 262144
net.core.wmem_max = 1048576
net.ipv4.tcp_tw_recycle = 1
net.ipv4.tcp_max_syn_backlog = 4096
net.core.netdev_max_backlog = 10000
vm.overcommit_memory = 0
net.ipv4.ip_conntrack_max = 655360
fs.aio-max-nr = 1048576
net.ipv4.tcp_timestamps = 0
1.2修改 /etc/security/limits.conf
* soft nofile 131072
* hard nofile 131072
* soft nproc 131072
* hard nproc 131072
* soft core unlimited
* hard core unlimited
* soft memlock 50000000
* hard memlock 50000000
1.3配置系统环境变量
export PS1="$USER@`/bin/hostname -s`-> "
export PGPORT=1921
export PGDATA=/opt/pgdata/pg_root
export LANG=en_US.utf8
export PGHOME=/opt/pgsql9.1.2
export LD_LIBRARY_PATH=$PGHOME/lib:/lib64:/usr/lib64:/usr/local/lib64:/lib:/usr/lib:/usr/local/lib
export DATE=`date +"%Y%m%d%H%M"`
export PATH=$PGHOME/bin:$PATH:.
export MANPATH=$PGHOME/share/man:$MANPATH
alias rm='rm -i'
alias ll='ls -lh'
1.4配置其他
防火墙，服务相关等等，这里根据需要就不再一一列举
2.安装PG(略)
3.在master建立流复制用户
create role repluser SUPERUSER LOGIN CONNECTION LIMIT 20 ENCRYPTED PASSWORD 'repluser';--注意这里满足login，replication权限即可，不是必须superuser。
4.master配置pg_hba,conf,添加以下：
host replication repluser 192.168.1.169/32 md5
5.master配置postgresql.conf
listen_addresses = '*' # what IP address(es) to listen on;
port = 1921 # (change requires restart)
max_connections = 2000 # (change requires restart)
unix_socket_directory = '/opt/pgdata/pg_root' # (change requires restart)
unix_socket_permissions = 0700 # begin with 0 to use octal notation
password_encryption = on
shared_buffers = 2048MB # min 128kB
maintenance_work_mem = 2048MB # min 1MB
max_stack_depth = 8MB # min 100kB
wal_level = hot_standby # minimal, archive, or hot_standby
synchronous_commit = off # immediate fsync at commit
wal_sync_method = fdatasync # the default is the first option
wal_buffers = 128000kB # min 32kB
wal_writer_delay = 20ms # 1-10000 milliseconds
checkpoint_segments = 64 # in logfile segments, min 1, 16MB each
checkpoint_timeout = 30min # range 30s-1h
archive_mode = on # allows archiving to be done
archive_command = '/bin/date' # command to use to archive a logfile segment
max_wal_senders = 30 # max number of walsender processes
wal_keep_segments = 1000 # in logfile segments, 16MB each; 0 disables;因为本例使用的logfile segment单个=64M,所以这里需要至少64*1000=64GB的pg_xlog目录
空间,否则可能空间溢出.
random_page_cost = 2.0 # same scale as above
effective_cache_size = 12800MB
constraint_exclusion = partition # on, off, or partition
log_destination = 'csvlog' # Valid values are combinations of
logging_collector = on # Enable capturing of stderr and csvlog
log_connections = on # 调试阶段建议主库和standby都打开log_connections,调试完后建议关闭.
log_directory = '/opt/pgdata/pg_log' # directory where log files are written,
log_filename = 'postgresql-%Y-%m-%d_%H%M%S.log' # log file name pattern,
log_truncate_on_rotation = on # If on, an existing log file of the
log_rotation_age = 1d # Automatic rotation of logfiles will
log_rotation_size = 10MB # Automatic rotation of logfiles will
log_min_duration_statement = 1000ms # -1 is disabled, 0 logs all statements
log_checkpoints = on
log_lock_waits = on # log lock waits >= deadlock_timeout
log_statement = 'ddl' # none, ddl, mod, all
track_activity_query_size = 2048 # (change requires restart)
autovacuum = on # Enable autovacuum subprocess? 'on'
log_autovacuum_min_duration = 0 # -1 disables, 0 logs all actions and
check_function_bodies = on
bytea_output = 'escape' # hex, escape
datestyle = 'iso, mdy'
lc_messages = 'C' # locale for system error message
lc_monetary = 'C' # locale for monetary formatting
lc_numeric = 'C' # locale for number formatting
lc_time = 'C' # locale for time formatting
default_text_search_config = 'pg_catalog.english'
deadlock_timeout = 1s
tcp_keepalives_idle = 60
6.启动master并对其进行全备一次
select pg_start_backup('replication backup');
将$PGDATA压缩传送的slave
select pg_stop_backup();
7.slave配置
相应的也是配置pg_hba.conf,postgressql.conf
host replication repluser 191.168.169.85/32 md5
slave配置hot_standby = on其他基本不需要修改，可以和master一致
除了配置以上的，slave还需要配置recovery.conf
#archive_cleanup_command = 'pg_archivecleanup $PGARCHIVE %r'
standby_mode = 'on'
trigger_file = '/opt/pgdata/pg_root/postgresql.trigger.1921'
primary_conninfo = 'host=192.168.1.168 port=1921 user=repluser password=repluser keepalives_idle=60'
修改
more ~/.pgpass
192.168.1.168:1921:replication:repluser:repluser:repluser
启动slave观察cvs日志
查看wal进程：
master：
wal sender process repluser 192.168.1.169(16494) streaming 0/70273E8
slave
postgres: wal receiver process streaming 0/70273E8
8.测试
建立数据库，用户，测试数据，注意表空间的一定要建好相关目录，而且要一主从节点一致，否则slave会直接关掉。
