一.部署说明

1.1 实施环境

本文档实验环境如下：

PGSQL主机: 192.168.1.45

PGSQL备机: 192.168.1.50

软件和系统版本

Pgsql 版本: pgsql 9.2.4

Linux 版本: Redhat 5.8

pgpool版本：pgpool-II version 3.3.4 (tokakiboshi)

1.2 文档说明　　

　　在postgresql 的stream replication配置一文我们实现了postgresql的stream replication，实现了postgresql的热备。而实际生产中集群的目的之一就是负载均衡。那我们系统为例，刚开始java程序需要修改数据源，将查询的压力分担给从机，对数据的修改设置为主机。但是这种方式不灵活，负载不能均衡，并且比较麻烦。所以如果此时有一个路由控制器多好，可以根据请求将请求分发给不同的数据库。刚好，pgpoool就是这么一个中间件，负责与数据库集群交互，对外提供统一的访问接口，使得程序对数据库的访问变得简单，提高整个系统的性能。本文主要配置pgpool的负载均衡，是在上篇博文：PostgreSQL的HA解决方案-1主从和备份（master/slave and backup） 的基础之上配置的。

　　为了试验减少不必要的麻烦，本系列试验中，各个主机之间的通信，都是设置为无密码访问，且关闭主从的防火墙，但对于实际生产，需要根据实际需要，配置密码，增强集群的安全性。

二.配置步骤

　　1.1 源码安装pgpool。参考中文手册：http://pgpool.projects.pgfoundry.org/pgpool-II/doc/pgpool-zh_cn.html#install。

　　1.2 安装pgpool中提供的工具。安装 pgpool_regclass。注意 pgpool_regclass是在你解压pgpool后的目录中的sql目录下，而不是你的安装目录。

　　　　pgpool_regclass主要作用是，方便在数据库查询中，查询关于pgpool的的配置参数，监控信息等，请仔细阅读中文手册。应在在每台通过 pgpool-II 访问的数据库中执行 pgpool-regclass.sql。你不需要在你执行“psql -f pgpool-regclass.sql template1”后建立的数据库中这么做，因为这个模板数据库将被克隆成新建的数据库。

cd pgpool-II-x.x.x/sql/pgpool-regclass

make

make install

psql -f pgpool-regclass.sql template1

　　　　安装之后，再在/usr/local/pgsql/share/extension/目录下多出如下文件：

-rw-r--r--  root root  Sep  : pgpool_regclass.control

-rw-r--r--  root root  Sep  : pgpool_regclass--1.0.sql

-rw-r--r--  root root  Sep  : pgpool-regclass.sql

　　1.3 配置pgpool的配置文件。

　　主要配置：

listen_addresses="*"

port=

backend_hostname0="localhost"

backend_port0=""

backend_weight0=

backend_hostname1="192.168.57.175"

backend_port1=""

backend_weight1=

replication_mode=off

load_balance_mode=on

master_slave_mode=on

master_save_sub_mode="stream"

parallel_mode=off

详细配置：

# ----------------------------

# pgPool-II configuration file

# ----------------------------

#

# This file consists of lines of the form:

#

#   name = value

#

# Whitespace may be used.  Comments are introduced with "#" anywhere on a line.

# The complete list of parameter names and allowed values can be found in the

# pgPool-II documentation.

#

# This file is read on server startup and when the server receives a SIGHUP

# signal.  If you edit the file on a running system, you have to SIGHUP the

# server for the changes to take effect, or use "pgpool reload".  Some

# parameters, which are marked below, require a server shutdown and restart to

# take effect.

#

#------------------------------------------------------------------------------

# CONNECTIONS

#------------------------------------------------------------------------------

# - pgpool Connection Settings -

#listen_addresses = 'localhost'

listen_addresses = '*'

                                   # Host name or IP address to listen on:

                                   # '*' for all, '' for no TCP/IP connections

                                   # (change requires restart)

port =

                                   # Port number

                                   # (change requires restart)

socket_dir = '/tmp'

                                   # Unix domain socket path

                                   # The Debian package defaults to

                                   # /var/run/postgresql

                                   # (change requires restart)

# - pgpool Communication Manager Connection Settings -

pcp_port =

                                   # Port number for pcp

                                   # (change requires restart)

pcp_socket_dir = '/tmp'

                                   # Unix domain socket path for pcp

                                   # The Debian package defaults to

                                   # /var/run/postgresql

                                   # (change requires restart)

# - Backend Connection Settings -

#backend_hostname0 = 'host1'

backend_hostname0 = '192.168.1.45'

                                   # Host name or IP address to connect to for backend

backend_port0 =

                                   # Port number for backend

backend_weight0 =

                                   # Weight for backend  (only in load balancing mode)

#backend_data_directory0 = '/data'

                                   # Data directory for backend

backend_flag0 = 'ALLOW_TO_FAILOVER'

                                   # Controls various backend behavior

                                   # ALLOW_TO_FAILOVER or DISALLOW_TO_FAILOVER

backend_hostname1 = '192.168.1.50'

backend_port1 =

backend_weight1 =

#backend_data_directory1 = '/data1'

backend_flag1 = 'ALLOW_TO_FAILOVER'

# - Authentication -

enable_pool_hba = on

                                   # Use pool_hba.conf for client authentication

pool_passwd = 'pool_passwd'

                                   # File name of pool_passwd for md5 authentication.

                                   # "" disables pool_passwd.

                                   # (change requires restart)

authentication_timeout =

                                   # Delay in seconds to complete client authentication

                                   #  means no timeout.

# - SSL Connections -

ssl = off

                                   # Enable SSL support

                                   # (change requires restart)

#ssl_key = './server.key'

                                   # Path to the SSL private key file

                                   # (change requires restart)

#ssl_cert = './server.cert'

                                   # Path to the SSL public certificate file

                                   # (change requires restart)

#ssl_ca_cert = ''

                                   # Path to a single PEM format file

                                   # containing CA root certificate(s)

                                   # (change requires restart)

#ssl_ca_cert_dir = ''

                                   # Directory containing CA root certificate(s)

                                   # (change requires restart)

#------------------------------------------------------------------------------

# POOLS

#------------------------------------------------------------------------------

# - Pool size -

num_init_children =

                                   # Number of pools

                                   # (change requires restart)

max_pool =

                                   # Number of connections per pool

                                   # (change requires restart)

# - Life time -

child_life_time =

                                   # Pool exits after being idle for this many seconds

child_max_connections =

                                   # Pool exits after receiving that many connections

                                   #  means no exit

connection_life_time =

                                   # Connection to backend closes after being idle for this many seconds

                                   #  means no close

client_idle_limit =

                                   # Client is disconnected after being idle for that many seconds

                                   # (even inside an explicit transactions!)

                                   #  means no disconnection

#------------------------------------------------------------------------------

# LOGS

#------------------------------------------------------------------------------

# - Where to log -

log_destination = 'stderr'

                                   # Where to log

                                   # Valid values are combinations of stderr,

                                   # and syslog. Default to stderr.

# - What to log -

print_timestamp = on

                                   # Print timestamp on each line

                                   # (change requires restart)

log_connections = on

                                   # Log connections

log_hostname = on

                                   # Hostname will be shown in ps status

                                   # and in logs if connections are logged

log_statement = on

                                   # Log all statements

log_per_node_statement = off

                                   # Log all statements

                                   # with node and backend informations

log_standby_delay = 'none'

                                   # Log standby delay

                                   # Valid values are combinations of always,

                                   # if_over_threshold, none

# - Syslog specific -

syslog_facility = 'LOCAL0'

                                   # Syslog local facility. Default to LOCAL0

syslog_ident = 'pgpool'

                                   # Syslog program identification string

                                   # Default to 'pgpool'

# - Debug -

debug_level =

                                   # Debug message verbosity level

                                   #  means no message,  or more mean verbose

#------------------------------------------------------------------------------

# FILE LOCATIONS

#------------------------------------------------------------------------------

pid_file_name = '/var/run/pgpool/pgpool.pid'

                                   # PID file name

                                   # (change requires restart)

logdir = '/tmp'

                                   # Directory of pgPool status file

                                   # (change requires restart)

#------------------------------------------------------------------------------

# CONNECTION POOLING

#------------------------------------------------------------------------------

connection_cache = on

                                   # Activate connection pools

                                   # (change requires restart)

                                   # Semicolon separated list of queries

                                   # to be issued at the end of a session

                                   # The default is for 8.3 and later

reset_query_list = 'ABORT; DISCARD ALL'

                                   # The following one is for 8.2 and before

#reset_query_list = 'ABORT; RESET ALL; SET SESSION AUTHORIZATION DEFAULT'

#------------------------------------------------------------------------------

# REPLICATION MODE

#------------------------------------------------------------------------------

replication_mode = off

                                   # Activate replication mode

                                   # (change requires restart)

replicate_select = off

                                   # Replicate SELECT statements

                                   # when in replication or parallel mode

                                   # replicate_select is higher priority than

                                   # load_balance_mode.

insert_lock = on

                                   # Automatically locks a dummy row or a table

                                   # with INSERT statements to keep SERIAL data

                                   # consistency

                                   # Without SERIAL, no lock will be issued

lobj_lock_table = ''

                                   # When rewriting lo_creat command in

                                   # replication mode, specify table name to

                                   # lock

# - Degenerate handling -

replication_stop_on_mismatch = off

                                   # On disagreement with the packet kind

                                   # sent from backend, degenerate the node

                                   # which is most likely "minority"

                                   # If off, just force to exit this session

failover_if_affected_tuples_mismatch = off

                                   # On disagreement with the number of affected

                                   # tuples in UPDATE/DELETE queries, then

                                   # degenerate the node which is most likely

                                   # "minority".

                                   # If off, just abort the transaction to

                                   # keep the consistency

#------------------------------------------------------------------------------

# LOAD BALANCING MODE

#------------------------------------------------------------------------------

load_balance_mode = on

                                   # Activate load balancing mode

                                   # (change requires restart)

ignore_leading_white_space = on

                                   # Ignore leading white spaces of each query

white_function_list = ''

                                   # Comma separated list of function names

                                   # that don't write to database

                                   # Regexp are accepted

black_function_list = 'nextval,setval'

                                   # Comma separated list of function names

                                   # that write to database

                                   # Regexp are accepted

#------------------------------------------------------------------------------

# MASTER/SLAVE MODE

#------------------------------------------------------------------------------

master_slave_mode = on

                                   # Activate master/slave mode

                                   # (change requires restart)

master_slave_sub_mode = 'stream'

                                   # Master/slave sub mode

                                   # Valid values are combinations slony or

                                   # stream. Default is slony.

                                   # (change requires restart)

# - Streaming -

#sr_check_period =

sr_check_period =

                                   # Streaming replication check period

                                   # Disabled () by default

sr_check_user = 'postgres'

                                   # Streaming replication check user

                                   # This is necessary even if you disable

                                   # streaming replication delay check with

                                   # sr_check_period =

sr_check_password = 'postgres123'

                                   # Password for streaming replication check user

delay_threshold =

                                   # Threshold before not dispatching query to standby node

                                   # Unit is in bytes

                                   # Disabled () by default

# - Special commands -

follow_master_command = ''

                                   # Executes this command after master failover

                                   # Special values:

                                   #   %d = node id

                                   #   %h = host name

                                   #   %p = port number

                                   #   %D = database cluster path

                                   #   %m = new master node id

                                   #   %H = hostname of the new master node

                                   #   %M = old master node id

                                   #   %P = old primary node id

                                   #   %r = new master port number

                                   #   %R = new master database cluster path

                                   #   %% = '%' character

#------------------------------------------------------------------------------

# PARALLEL MODE

#------------------------------------------------------------------------------

parallel_mode = off

                                   # Activates parallel query mode

                                   # (change requires restart)

pgpool2_hostname = ''

                                   # Set pgpool2 hostname

                                   # (change requires restart)

# - System DB info -

system_db_hostname  = 'localhost'

                                   # (change requires restart)

system_db_port =

                                   # (change requires restart)

system_db_dbname = 'pgpool'

                                   # (change requires restart)

system_db_schema = 'pgpool_catalog'

                                   # (change requires restart)

system_db_user = 'pgpool'

                                   # (change requires restart)

system_db_password = ''

                                   # (change requires restart)

#------------------------------------------------------------------------------

# HEALTH CHECK

#------------------------------------------------------------------------------

#health_check_period =

health_check_period =

                                   # Health check period

                                   # Disabled () by default

health_check_timeout =

                                   # Health check timeout

                                   #  means no timeout

health_check_user = 'postgres'

                                   # Health check user

health_check_password = 'postgres123'

                                   # Password for health check user

health_check_max_retries =

                                   # Maximum number of times to retry a failed health check before giving up.

health_check_retry_delay =

                                   # Amount of time to wait (in seconds) between retries.

#------------------------------------------------------------------------------

# FAILOVER AND FAILBACK

#------------------------------------------------------------------------------

failover_command = '/home/postgres/scripts/failover_stream.sh %d %H /usr/local/pgsql/data/postgresql.trigger.5432'

                                   # Executes this command at failover

                                   # Special values:

                                   #   %d = node id

                                   #   %h = host name

                                   #   %p = port number

                                   #   %D = database cluster path

                                   #   %m = new master node id

                                   #   %H = hostname of the new master node

                                   #   %M = old master node id

                                   #   %P = old primary node id

                                   #   %r = new master port number

                                   #   %R = new master database cluster path

                                   #   %% = '%' character

failback_command = ''

                                   # Executes this command at failback.

                                   # Special values:

                                   #   %d = node id

                                   #   %h = host name

                                   #   %p = port number

                                   #   %D = database cluster path

                                   #   %m = new master node id

                                   #   %H = hostname of the new master node

                                   #   %M = old master node id

                                   #   %P = old primary node id

                                   #   %r = new master port number

                                   #   %R = new master database cluster path

                                   #   %% = '%' character

fail_over_on_backend_error = on

                                   # Initiates failover when reading/writing to the

                                   # backend communication socket fails

                                   # If set to off, pgpool will report an

                                   # error and disconnect the session.

search_primary_node_timeout =

                                   # Timeout in seconds to search for the

                                   # primary node when a failover occurs.

                                   #  means no timeout, keep searching

                                   # for a primary node forever.

#------------------------------------------------------------------------------

# ONLINE RECOVERY

#------------------------------------------------------------------------------

recovery_user = 'postgres'

                                   # Online recovery user

recovery_password = 'postgres123'

                                   # Online recovery password

recovery_1st_stage_command = ''

                                   # Executes a command in first stage

recovery_2nd_stage_command = ''

                                   # Executes a command in second stage

recovery_timeout =

                                   # Timeout in seconds to wait for the

                                   # recovering node's postmaster to start up

                                   #  means no wait

client_idle_limit_in_recovery =

                                   # Client is disconnected after being idle

                                   # for that many seconds in the second stage

                                   # of online recovery

                                   #  means no disconnection

                                   # - means immediate disconnection

#------------------------------------------------------------------------------

# WATCHDOG

#------------------------------------------------------------------------------

# - Enabling -

use_watchdog = off

                                    # Activates watchdog

                                    # (change requires restart)

# -Connection to up stream servers -

trusted_servers = ''

                                    # trusted server list which are used

                                    # to confirm network connection

                                    # (hostA,hostB,hostC,...)

                                    # (change requires restart)

ping_path = '/bin'

                                    # ping command path

                                    # (change requires restart)

# - Watchdog communication Settings -

wd_hostname = ''

                                    # Host name or IP address of this watchdog

                                    # (change requires restart)

wd_port =

                                    # port number for watchdog service

                                    # (change requires restart)

wd_authkey = ''

                                    # Authentication key for watchdog communication

                                    # (change requires restart)

# - Virtual IP control Setting -

delegate_IP = ''

                                    # delegate IP address

                                    # If this is empty, virtual IP never bring up.

                                    # (change requires restart)

ifconfig_path = '/sbin'

                                    # ifconfig command path

                                    # (change requires restart)

if_up_cmd = 'ifconfig eth0:0 inet $_IP_$ netmask 255.255.255.0'

                                    # startup delegate IP command

                                    # (change requires restart)

if_down_cmd = 'ifconfig eth0:0 down'

                                    # shutdown delegate IP command

                                    # (change requires restart)

arping_path = '/usr/sbin'           # arping command path

                                    # (change requires restart)

arping_cmd = 'arping -U $_IP_$ -w 1'

                                    # arping command

                                    # (change requires restart)

# - Behaivor on escalation Setting -

clear_memqcache_on_escalation = on

                                    # Clear all the query cache on shared memory

                                    # when standby pgpool escalate to active pgpool

                                    # (= virtual IP holder).

                                    # This should be off if client connects to pgpool

                                    # not using virtual IP.

                                    # (change requires restart)

wd_escalation_command = ''

                                    # Executes this command at escalation on new active pgpool.

                                    # (change requires restart)

# - Lifecheck Setting - 

# -- common --

wd_lifecheck_method = 'heartbeat'

                                    # Method of watchdog lifecheck ('heartbeat' or 'query')

                                    # (change requires restart)

wd_interval =

                                    # lifecheck interval (sec) >

                                    # (change requires restart)

# -- heartbeat mode --

wd_heartbeat_port =

                                    # Port number for receiving heartbeat signal

                                    # (change requires restart)

wd_heartbeat_keepalive =

                                    # Interval time of sending heartbeat signal (sec)

                                    # (change requires restart)

wd_heartbeat_deadtime =

                                    # Deadtime interval for heartbeat signal (sec)

                                    # (change requires restart)

heartbeat_destination0 = 'db2'

                                    # Host name or IP address of destination

                                    # for sending heartbeat signal.

                                    # (change requires restart)

heartbeat_destination_port0 =

                                    # Port number of destination  for sending

                                    # heartbeat signal. Usually this is the

                                    # same as wd_heartbeat_port.

                                    # (change requires restart)

heartbeat_device0 = ''

                                    # Name of NIC device (such like 'eth0')

                                    # used for sending/receiving heartbeat

                                    # signal to/from destination .

                                    # This works only when this is not empty

                                    # and pgpool has root privilege.

                                    # (change requires restart)

#heartbeat_destination1 = 'host0_ip2'

#heartbeat_destination_port1 =

#heartbeat_device1 = ''

# -- query mode --

wd_life_point =

                                    # lifecheck retry times

                                    # (change requires restart)

wd_lifecheck_query = 'SELECT 1'

                                    # lifecheck query to pgpool from watchdog

                                    # (change requires restart)

wd_lifecheck_dbname = 'template1'

                                    # Database name connected for lifecheck

                                    # (change requires restart)

wd_lifecheck_user = 'nobody'

                                    # watchdog user monitoring pgpools in lifecheck

                                    # (change requires restart)

wd_lifecheck_password = ''

                                    # Password for watchdog user in lifecheck

                                    # (change requires restart)

# - Other pgpool Connection Settings -

#other_pgpool_hostname0 = 'host0'

                                    # Host name or IP address to connect to for other pgpool

                                    # (change requires restart)

#other_pgpool_port0 =

                                    # Port number for othet pgpool

                                    # (change requires restart)

#other_wd_port0 =

                                    # Port number for othet watchdog

                                    # (change requires restart)

#other_pgpool_hostname1 = 'host1'

#other_pgpool_port1 =

#other_wd_port1 = 

#------------------------------------------------------------------------------

# OTHERS

#------------------------------------------------------------------------------

relcache_expire =

                                   # Life time of relation cache in seconds.

                                   #  means no cache expiration(the default).

                                   # The relation cache is used for cache the

                                   # query result against PostgreSQL system

                                   # catalog to obtain various information

                                   # including table structures or if it's a

                                   # temporary table or not. The cache is

                                   # maintained in a pgpool child local memory

                                   # and being kept as long as it survives.

                                   # If someone modify the table by using

                                   # ALTER TABLE or some such, the relcache is

                                   # not consistent anymore.

                                   # For this purpose, cache_expiration

                                   # controls the life time of the cache.

relcache_size =

                                   # Number of relation cache

                                   # entry. If you see frequently:

                                   # "pool_search_relcache: cache replacement happend"

                                   # in the pgpool log, you might want to increate this number.

check_temp_table = on

                                   # If on, enable temporary table check in SELECT statements.

                                   # This initiates queries against system catalog of primary/master

                                   # thus increases load of master.

                                   # If you are absolutely sure that your system never uses temporary tables

                                   # and you want to save access to primary/master, you could turn this off.

                                   # Default is on.

#------------------------------------------------------------------------------

# ON MEMORY QUERY MEMORY CACHE

#------------------------------------------------------------------------------

memory_cache_enabled = off

                                   # If on, use the memory cache functionality, off by default

memqcache_method = 'shmem'

                                   # Cache storage method. either 'shmem'(shared memory) or

                                   # 'memcached'. 'shmem' by default

                                   # (change requires restart)

memqcache_memcached_host = 'localhost'

                                   # Memcached host name or IP address. Mandatory if

                                   # memqcache_method = 'memcached'.

                                   # Defaults to localhost.

                                   # (change requires restart)

memqcache_memcached_port =

                                   # Memcached port number. Mondatory if memqcache_method = 'memcached'.

                                   # Defaults to .

                                   # (change requires restart)

memqcache_total_size =

                                   # Total memory size in bytes for storing memory cache.

                                   # Mandatory if memqcache_method = 'shmem'.

                                   # Defaults to 64MB.

                                   # (change requires restart)

memqcache_max_num_cache =

                                   # Total number of cache entries. Mandatory

                                   # if memqcache_method = 'shmem'.

                                   # Each cache entry consumes  bytes on shared memory.

                                   # Defaults to ,,(.8MB).

                                   # (change requires restart)

memqcache_expire =

                                   # Memory cache entry life time specified in seconds.

                                   #  means infinite life time.  by default.

                                   # (change requires restart)

memqcache_auto_cache_invalidation = on

                                   # If on, invalidation of query cache is triggered by corresponding

                                   # DDL/DML/DCL(and memqcache_expire).  If off, it is only triggered

                                   # by memqcache_expire.  on by default.

                                   # (change requires restart)

memqcache_maxcache =

                                   # Maximum SELECT result size in bytes.

                                   # Must be smaller than memqcache_cache_block_size. Defaults to 400KB.

                                   # (change requires restart)

memqcache_cache_block_size =

                                   # Cache block size in bytes. Mandatory if memqcache_method = 'shmem'.

                                   # Defaults to 1MB.

                                   # (change requires restart)

memqcache_oiddir = '/var/log/pgpool/oiddir'

                                      # Temporary work directory to record table oids

                                   # (change requires restart)

white_memqcache_table_list = ''

                                   # Comma separated list of table names to memcache

                                   # that don't write to database

                                   # Regexp are accepted

black_memqcache_table_list = ''

                                   # Comma separated list of table names not to memcache

                                   # that don't write to database

                                   # Regexp are accepted

　　1.4 启动pgpool：pgpool -dn 以非守护进程，调试模式运行pgpool，因为如果默认是守护进程，待会想停止就麻烦了。其他参数--help.

注意观察调试信息。如果有错误，请重新查看配置文件。如果没有法相错误，使用命令：psql -p 9999 ，通过pgpool进入数据库。如果可以进入就说明pgpool监听的9999正常，且成功连接数据库。

　　此时使用如下命令查看监听的数据库信息：当发现status为3时，使用ping、telnet、psql -h进行测试网络连通性。关闭防火墙。

postgres=# show pool_nodes;

 node_id |   hostname   | port | status | lb_weight |  role

---------+--------------+------+--------+-----------+---------

        | 192.168.1.45 |  |       | 0.500000  | primary

        | 192.168.1.50 |  |       | 0.500000  | standby

　　当然，可以启动主从数据库的日志级别为 all。那么对数据的一切操作，都可以查看到。此时可以使用脚本测试一下。就可以查看主从的日志。看看是否都有日志记录。

for i in {..}; do echo $i; psql -p  -U postgres -h 192.168.1.45 -d postgres -c "select * from test"; done

　　1.5 查看pgpool的状态。参考手册：http://pgpool.projects.pgfoundry.org/pgpool-II/doc/pgpool-zh_cn.html#show-commands

　　之前安装的regclass就是通过psql查看pgpool状态的工具。可以运行下列命令查看：

pgpool-II 通过 SHOW 命令提供一些信息。SHOW 是一个真实的 SQL 语句, 但是如果该命令查询 pgpool-II 信息的话，pgpool-II 解释了该命令。可选项如下:

pool_status, 获取配置

pool_nodes, 获取节点信息

pool_processes, 获取pgPool-II 进程信息

pool_pools, 获取pgPool-II 所有的连接池信息

pool_version, 获取pgPool_II 版本信息

　　比如：pool_processes。查看进程池的情况。可以根据需要修改pgpool中的设置。

postgres=# show pool_processes;

 pool_pid |     start_time      | database | username |     create_time     | pool_counter

----------+---------------------+----------+----------+---------------------+--------------

     | -- :: | postgres | postgres | -- :: |

     | -- :: |          |          |                     |

     | -- :: |          |          |                     |

     | -- :: |          |          |                     |

     | -- :: |          |          |                     |

     | -- :: |          |          |                     |

     | -- :: |          |          |                     |

     | -- :: |          |          |                     |

     | -- :: |          |          |                     |

     | -- :: |          |          |                     |

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