环境： CentOS Linux release 7.6.1810 (Core) 内核版本:3.10.0-957.10.1.el7.x86_64

node1:192.168.216.130

node2:192.168.216.132

node3:192.168.216.134

postgres内核优化指南：https://github.com/digoal/blog/blob/master/201611/20161121_01.md?spm=a2c4e.10696291.0.0.660a19a4sIk1Ok&file=20161121_01.md

一、安装postgres

yum install https://download.postgresql.org/pub/repos/yum/11/redhat/rhel-7-x86_64/pgdg-centos11-11-2.noarch.rpm

yum install postgresql11

yum install postgresql11-server

yum install postgresql11-libs

yum install postgresql11-contrib

yum install postgresql11-devel

可以参考：https://www.jianshu.com/p/b4a759c2208f

安装完成后可以查询下rpm -qa|grep postgres安装了哪些包

postgresql11-libs-11.5-1PGDG.rhel7.x86_64

postgresql10-libs-10.10-1PGDG.rhel7.x86_64

postgresql11-11.5-1PGDG.rhel7.x86_64

postgresql11-contrib-11.5-1PGDG.rhel7.x86_64

postgresql11-server-11.5-1PGDG.rhel7.x86_64

postgresql11-devel-11.5-1PGDG.rhel7.x86_64

安装后不需要初始化，可由patroni来完成初始化操作,如果已经初始化完成,不需要patroni来初始化操作，可以修改patroni配置文件的以下参数来指定data目录和安装目录

data_dir: /var/lib/pgsql/11/data

bin_dir: /usr/pgsql-11/bin

config_dir: /var/lib/pgsql/11/data

stats_temp_directory: /var/lib/pgsql_stats_tmp

chown -Rf postgres:postgres /var/lib/pgsql/11/data

chmod -Rf 700 /var/lib/pgsql/11/data

chown -Rf postgres:postgres /var/lib/pgsql_stats_tmp

chmod -Rf 700 /var/lib/pgsql_stats_tmp

二、安装patroni,这里建议先修改pip源为国内，否则在安装过程中可能遇到大量超时问题

可参考：https://www.cnblogs.com/caidingyu/p/11566690.html

yum install gcc

yum install python-devel.x86_64

curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py

python get-pip.py

pip install psycopg2-binary

pip install patroni[etcd,consul]

三、安装etcd服务

可参考：https://www.cnblogs.com/caidingyu/p/11408389.html

四、创建patroni的配置文件

node1：patroni配置文件如下

[root@localhost tmp]# cat /etc/patroni/patroni.yml 

scope: postgres-cluster

name: pgnode01

namespace: /service/

restapi:

  listen: 192.168.216.130:8008

  connect_address: 192.168.216.130:8008

#  certfile: /etc/ssl/certs/ssl-cert-snakeoil.pem

#  keyfile: /etc/ssl/private/ssl-cert-snakeoil.key

#  authentication:

#    username: username

#    password: password

etcd:

  hosts: 192.168.216.130:2379,192.168.216.132:2379,192.168.216.134:2379

bootstrap:

  # this section will be written into Etcd:/<namespace>/<scope>/config after initializing new cluster

  # and all other cluster members will use it as a `global configuration`

  dcs:

    ttl: 30

    loop_wait: 10

    retry_timeout: 10

    maximum_lag_on_failover: 1048576

    master_start_timeout: 300

    synchronous_mode: false

    synchronous_mode_strict: false

    #standby_cluster:

      #host: 127.0.0.1

      #port: 1111

      #primary_slot_name: patroni

    postgresql:

      use_pg_rewind: true

      use_slots: true

      parameters:

        max_connections: 100

        superuser_reserved_connections: 5

        max_locks_per_transaction: 64

        max_prepared_transactions: 0

        huge_pages: try

        shared_buffers: 512MB

        work_mem: 128MB

        maintenance_work_mem: 256MB

        effective_cache_size: 4GB

        checkpoint_timeout: 15min

        checkpoint_completion_target: 0.9

        min_wal_size: 2GB

        max_wal_size: 4GB

        wal_buffers: 32MB

        default_statistics_target: 1000

        seq_page_cost: 1

        random_page_cost: 4

        effective_io_concurrency: 2

        synchronous_commit: on

        autovacuum: on

        autovacuum_max_workers: 5

        autovacuum_vacuum_scale_factor: 0.01

        autovacuum_analyze_scale_factor: 0.02

        autovacuum_vacuum_cost_limit: 200

        autovacuum_vacuum_cost_delay: 20

        autovacuum_naptime: 1s

        max_files_per_process: 4096

        archive_mode: on

        archive_timeout: 1800s

        archive_command: cd .

        wal_level: replica

        wal_keep_segments: 130

        max_wal_senders: 10

        max_replication_slots: 10

        hot_standby: on

        wal_log_hints: on

        shared_preload_libraries: pg_stat_statements,auto_explain

        pg_stat_statements.max: 10000

        pg_stat_statements.track: all

        pg_stat_statements.save: off

        auto_explain.log_min_duration: 10s

        auto_explain.log_analyze: true

        auto_explain.log_buffers: true

        auto_explain.log_timing: false

        auto_explain.log_triggers: true

        auto_explain.log_verbose: true

        auto_explain.log_nested_statements: true

        track_io_timing: on

        log_lock_waits: on

        log_temp_files: 0

        track_activities: on

        track_counts: on

        track_functions: all

        log_checkpoints: on

        logging_collector: on

        log_truncate_on_rotation: on

        log_rotation_age: 1d

        log_rotation_size: 0

        log_line_prefix: '%t [%p-%l] %r %q%u@%d '

        log_filename: 'postgresql-%a.log'

        log_directory: /var/log/postgresql

 #      recovery_conf:

#        restore_command: cp ../wal_archive/%f %p

  # some desired options for 'initdb'

  initdb:  # Note: It needs to be a list (some options need values, others are switches)

  - encoding: UTF8

  - locale: en_US.UTF-8

  - data-checksums

  pg_hba:  # Add following lines to pg_hba.conf after running 'initdb'

  - host replication replicator 0.0.0.0/0 md5

  - host all all 0.0.0.0/0 md5

 # Additional script to be launched after initial cluster creation (will be passed the connection URL as parameter)

# post_init: /usr/local/bin/setup_cluster.sh

  # Some additional users which needs to be created after initializing new cluster

#  users:

#    admin:

#      password: admin-pass

#      options:

#        - createrole

#        - createdb

postgresql:

  listen: 192.168.216.130,127.0.0.1:5432

  connect_address: 192.168.216.130:5432

  use_unix_socket: true

  data_dir: /var/lib/pgsql/11/data

  bin_dir: /usr/pgsql-11/bin

  config_dir: /var/lib/pgsql/11/data

  pgpass: /var/lib/pgsql/.pgpass

  authentication:

    replication:

      username: replicator

      password: replicator-pass

    superuser:

      username: postgres

      password: postgres-pass

#    rewind:  # Has no effect on postgres 10 and lower

#      username: rewind_user

#      password: rewind_password

  parameters:

    unix_socket_directories: /var/run/postgresql

    stats_temp_directory: /var/lib/pgsql_stats_tmp

#  callbacks:

#    on_start:

#    on_stop:

#    on_restart:

#    on_reload:

#    on_role_change:

  create_replica_methods:

#   - pgbackrest

#   - wal_e

   - basebackup

# pgbackrest:

#   command: /usr/bin/pgbackrest --stanza=<Stanza_Name> --delta restore

#   keep_data: True

#   no_params: True

#  wal_e

#    command: patroni_wale_restore

#    no_master: 1

#    envdir: /etc/wal_e/envdir

#    use_iam: 1

  basebackup:

    max-rate: '100M'

 #watchdog:

#  mode: automatic # Allowed values: off, automatic, required

#  device: /dev/watchdog

#  safety_margin: 5

tags:

    nofailover: false

    noloadbalance: false

    clonefrom: false

    nosync: false

# specify a node to replicate from. This can be used to implement a cascading replication.

#    replicatefrom: (node name)

node2：patroni配置文件如下

[root@localhost postgresql]# cat /etc/patroni/patroni.yml 

scope: postgres-cluster

name: pgnode02

namespace: /service/

restapi:

  listen: 192.168.216.132:8008

  connect_address: 192.168.216.132:8008

#  certfile: /etc/ssl/certs/ssl-cert-snakeoil.pem

#  keyfile: /etc/ssl/private/ssl-cert-snakeoil.key

#  authentication:

#    username: username

#    password: password

etcd:

  hosts: 192.168.216.130:2379,192.168.216.132:2379,192.168.216.134:2379

bootstrap:

  # this section will be written into Etcd:/<namespace>/<scope>/config after initializing new cluster

  # and all other cluster members will use it as a `global configuration`

  dcs:

    ttl: 30

    loop_wait: 10

    retry_timeout: 10

    maximum_lag_on_failover: 1048576

    master_start_timeout: 300

    synchronous_mode: false

    synchronous_mode_strict: false

    #standby_cluster:

      #host: 127.0.0.1

      #port: 1111

      #primary_slot_name: patroni

    postgresql:

      use_pg_rewind: true

      use_slots: true

      parameters:

        max_connections: 100

        superuser_reserved_connections: 5

        max_locks_per_transaction: 64

        max_prepared_transactions: 0

        huge_pages: try

        shared_buffers: 512MB

        work_mem: 128MB

        maintenance_work_mem: 256MB

        effective_cache_size: 4GB

        checkpoint_timeout: 15min

        checkpoint_completion_target: 0.9

        min_wal_size: 2GB

        max_wal_size: 4GB

        wal_buffers: 32MB

        default_statistics_target: 1000

        seq_page_cost: 1

        random_page_cost: 4

        effective_io_concurrency: 2

        synchronous_commit: on

        autovacuum: on

        autovacuum_max_workers: 5

        autovacuum_vacuum_scale_factor: 0.01

        autovacuum_analyze_scale_factor: 0.02

        autovacuum_vacuum_cost_limit: 200

        autovacuum_vacuum_cost_delay: 20

        autovacuum_naptime: 1s

        max_files_per_process: 4096

        archive_mode: on

        archive_timeout: 1800s

        archive_command: cd .

        wal_level: replica

        wal_keep_segments: 130

        max_wal_senders: 10

        max_replication_slots: 10

        hot_standby: on

        wal_log_hints: on

        shared_preload_libraries: pg_stat_statements,auto_explain

        pg_stat_statements.max: 10000

        pg_stat_statements.track: all

        pg_stat_statements.save: off

        auto_explain.log_min_duration: 10s

        auto_explain.log_analyze: true

        auto_explain.log_buffers: true

        auto_explain.log_timing: false

        auto_explain.log_triggers: true

        auto_explain.log_verbose: true

        auto_explain.log_nested_statements: true

        track_io_timing: on

        log_lock_waits: on

        log_temp_files: 0

        track_activities: on

        track_counts: on

        track_functions: all

        log_checkpoints: on

        logging_collector: on

        log_truncate_on_rotation: on

        log_rotation_age: 1d

        log_rotation_size: 0

        log_line_prefix: '%t [%p-%l] %r %q%u@%d '

        log_filename: 'postgresql-%a.log'

        log_directory: /var/log/postgresql

 #      recovery_conf:

#        restore_command: cp ../wal_archive/%f %p

  # some desired options for 'initdb'

  initdb:  # Note: It needs to be a list (some options need values, others are switches)

  - encoding: UTF8

  - locale: en_US.UTF-8

  - data-checksums

  pg_hba:  # Add following lines to pg_hba.conf after running 'initdb'

  - host replication replicator 0.0.0.0/0 md5

  - host all all 0.0.0.0/0 md5

 # Additional script to be launched after initial cluster creation (will be passed the connection URL as parameter)

# post_init: /usr/local/bin/setup_cluster.sh

  # Some additional users which needs to be created after initializing new cluster

#  users:

#    admin:

#      password: admin-pass

#      options:

#        - createrole

#        - createdb

postgresql:

  listen: 192.168.216.132,127.0.0.1:5432

  connect_address: 192.168.216.132:5432

  use_unix_socket: true

  data_dir: /var/lib/pgsql/11/data

  bin_dir: /usr/pgsql-11/bin

  config_dir: /var/lib/pgsql/11/data

  pgpass: /var/lib/pgsql/.pgpass

  authentication:

    replication:

      username: replicator

      password: replicator-pass

    superuser:

      username: postgres

      password: postgres-pass

#    rewind:  # Has no effect on postgres 10 and lower

#      username: rewind_user

#      password: rewind_password

  parameters:

    unix_socket_directories: /var/run/postgresql

    stats_temp_directory: /var/lib/pgsql_stats_tmp

#  callbacks:

#    on_start:

#    on_stop:

#    on_restart:

#    on_reload:

#    on_role_change:

  create_replica_methods:

#   - pgbackrest

#   - wal_e

   - basebackup

# pgbackrest:

#   command: /usr/bin/pgbackrest --stanza=<Stanza_Name> --delta restore

#   keep_data: True

#   no_params: True

#  wal_e

#    command: patroni_wale_restore

#    no_master: 1

#    envdir: /etc/wal_e/envdir

#    use_iam: 1

  basebackup:

    max-rate: '100M'

 #watchdog:

#  mode: automatic # Allowed values: off, automatic, required

#  device: /dev/watchdog

#  safety_margin: 5

tags:

    nofailover: false

    noloadbalance: false

    clonefrom: false

    nosync: false

# specify a node to replicate from. This can be used to implement a cascading replication.

#    replicatefrom: (node name)

node3：patroni配置文件如下

[root@localhost tmp]# cat /etc/patroni/patroni.yml 

scope: postgres-cluster

name: pgnode03

namespace: /service/

restapi:

  listen: 192.168.216.134:8008

  connect_address: 192.168.216.134:8008

#  certfile: /etc/ssl/certs/ssl-cert-snakeoil.pem

#  keyfile: /etc/ssl/private/ssl-cert-snakeoil.key

#  authentication:

#    username: username

#    password: password

etcd:

  hosts: 192.168.216.130:2379,192.168.216.132:2379,192.168.216.134:2379

bootstrap:

  # this section will be written into Etcd:/<namespace>/<scope>/config after initializing new cluster

  # and all other cluster members will use it as a `global configuration`

  dcs:

    ttl: 30

    loop_wait: 10

    retry_timeout: 10

    maximum_lag_on_failover: 1048576

    master_start_timeout: 300

    synchronous_mode: false

    synchronous_mode_strict: false

    #standby_cluster:

      #host: 127.0.0.1

      #port: 1111

      #primary_slot_name: patroni

    postgresql:

      use_pg_rewind: true

      use_slots: true

      parameters:

        max_connections: 100

        superuser_reserved_connections: 5

        max_locks_per_transaction: 64

        max_prepared_transactions: 0

        huge_pages: try

        shared_buffers: 512MB

        work_mem: 128MB

        maintenance_work_mem: 256MB

        effective_cache_size: 4GB

        checkpoint_timeout: 15min

        checkpoint_completion_target: 0.9

        min_wal_size: 2GB

        max_wal_size: 4GB

        wal_buffers: 32MB

        default_statistics_target: 1000

        seq_page_cost: 1

        random_page_cost: 4

        effective_io_concurrency: 2

        synchronous_commit: on

        autovacuum: on

        autovacuum_max_workers: 5

        autovacuum_vacuum_scale_factor: 0.01

        autovacuum_analyze_scale_factor: 0.02

        autovacuum_vacuum_cost_limit: 200

        autovacuum_vacuum_cost_delay: 20

        autovacuum_naptime: 1s

        max_files_per_process: 4096

        archive_mode: on

        archive_timeout: 1800s

        archive_command: cd .

        wal_level: replica

        wal_keep_segments: 130

        max_wal_senders: 10

        max_replication_slots: 10

        hot_standby: on

        wal_log_hints: on

        shared_preload_libraries: pg_stat_statements,auto_explain

        pg_stat_statements.max: 10000

        pg_stat_statements.track: all

        pg_stat_statements.save: off

        auto_explain.log_min_duration: 10s

        auto_explain.log_analyze: true

        auto_explain.log_buffers: true

        auto_explain.log_timing: false

        auto_explain.log_triggers: true

        auto_explain.log_verbose: true

        auto_explain.log_nested_statements: true

        track_io_timing: on

        log_lock_waits: on

        log_temp_files: 0

        track_activities: on

        track_counts: on

        track_functions: all

        log_checkpoints: on

        logging_collector: on

        log_truncate_on_rotation: on

        log_rotation_age: 1d

        log_rotation_size: 0

        log_line_prefix: '%t [%p-%l] %r %q%u@%d '

        log_filename: 'postgresql-%a.log'

        log_directory: /var/log/postgresql

 #      recovery_conf:

#        restore_command: cp ../wal_archive/%f %p

  # some desired options for 'initdb'

  initdb:  # Note: It needs to be a list (some options need values, others are switches)

  - encoding: UTF8

  - locale: en_US.UTF-8

  - data-checksums

  pg_hba:  # Add following lines to pg_hba.conf after running 'initdb'

  - host replication replicator 0.0.0.0/0 md5

  - host all all 0.0.0.0/0 md5

 # Additional script to be launched after initial cluster creation (will be passed the connection URL as parameter)

# post_init: /usr/local/bin/setup_cluster.sh

  # Some additional users which needs to be created after initializing new cluster

#  users:

#    admin:

#      password: admin-pass

#      options:

#        - createrole

#        - createdb

postgresql:

  listen: 192.168.216.134,127.0.0.1:5432

  connect_address: 192.168.216.134:5432

  use_unix_socket: true

  data_dir: /var/lib/pgsql/11/data

  bin_dir: /usr/pgsql-11/bin

  config_dir: /var/lib/pgsql/11/data

  pgpass: /var/lib/pgsql/.pgpass

  authentication:

    replication:

      username: replicator

      password: replicator-pass

    superuser:

      username: postgres

      password: postgres-pass

#    rewind:  # Has no effect on postgres 10 and lower

#      username: rewind_user

#      password: rewind_password

  parameters:

    unix_socket_directories: /var/run/postgresql

    stats_temp_directory: /var/lib/pgsql_stats_tmp

#  callbacks:

#    on_start:

#    on_stop:

#    on_restart:

#    on_reload:

#    on_role_change:

  create_replica_methods:

#   - pgbackrest

#   - wal_e

   - basebackup

# pgbackrest:

#   command: /usr/bin/pgbackrest --stanza=<Stanza_Name> --delta restore

#   keep_data: True

#   no_params: True

#  wal_e

#    command: patroni_wale_restore

#    no_master: 1

#    envdir: /etc/wal_e/envdir

#    use_iam: 1

  basebackup:

    max-rate: '100M'

 #watchdog:

#  mode: automatic # Allowed values: off, automatic, required

#  device: /dev/watchdog

#  safety_margin: 5

tags:

    nofailover: false

    noloadbalance: false

    clonefrom: false

    nosync: false

# specify a node to replicate from. This can be used to implement a cascading replication.

#    replicatefrom: (node name)

五、分别在3个node节点上创建/etc/systemd/system/patroni.service来通过systemctl管理patroni服务

可以先执行下，确认patroni的安装位置

which patroni

如果安装位置和patroni.service配置中的不一致，可以采用创建软连接的方式，

1、创建软连接(或者手动修改patroni.service中patroni的路径为实际路径，即：ExecStart=patroni的实际路径)

ln -s /usr/bin/patronictl /usr/local/bin/patronictl

ln -s /usr/bin/patroni /usr/local/bin/patroni

2、在Node1上创建/etc/systemd/system/patroni.service

cat /etc/systemd/system/patroni.service

[Unit]

Description=Runners to orchestrate a high-availability PostgreSQL - patroni

After=syslog.target network.target

[Service]

Type=simple

User=postgres

Group=postgres

# Read in configuration file if it exists, otherwise proceed

EnvironmentFile=-/etc/patroni_env.conf

WorkingDirectory=~

# Where to send early-startup messages from the server

# This is normally controlled by the global default set by systemd

# StandardOutput=syslog

# Pre-commands to start watchdog device

# Uncomment if watchdog is part of your patroni setup

#ExecStartPre=-/usr/bin/sudo /sbin/modprobe softdog

#ExecStartPre=-/usr/bin/sudo /bin/chown postgres /dev/watchdog

# Start the patroni process

ExecStart=/usr/local/bin/patroni /etc/patroni/patroni.yml

# Send HUP to reload from patroni.yml

ExecReload=/bin/kill -s HUP $MAINPID

# only kill the patroni process, not it's children, so it will gracefully stop postgres

KillMode=process

# Give a reasonable amount of time for the server to start up/shut down

TimeoutSec=60

# Do not restart the service if it crashes, we want to manually inspect database on failure

Restart=no

[Install]

WantedBy=multi-user.target

3、在Node2上创建/etc/systemd/system/patroni.service

cat /etc/systemd/system/patroni.service

[Unit]

Description=Runners to orchestrate a high-availability PostgreSQL - patroni

After=syslog.target network.target

[Service]

Type=simple

User=postgres

Group=postgres

# Read in configuration file if it exists, otherwise proceed

EnvironmentFile=-/etc/patroni_env.conf

WorkingDirectory=~

# Where to send early-startup messages from the server

# This is normally controlled by the global default set by systemd

# StandardOutput=syslog

# Pre-commands to start watchdog device

# Uncomment if watchdog is part of your patroni setup

#ExecStartPre=-/usr/bin/sudo /sbin/modprobe softdog

#ExecStartPre=-/usr/bin/sudo /bin/chown postgres /dev/watchdog

# Start the patroni process

ExecStart=/usr/local/bin/patroni /etc/patroni/patroni.yml

# Send HUP to reload from patroni.yml

ExecReload=/bin/kill -s HUP $MAINPID

# only kill the patroni process, not it's children, so it will gracefully stop postgres

KillMode=process

# Give a reasonable amount of time for the server to start up/shut down

TimeoutSec=60

# Do not restart the service if it crashes, we want to manually inspect database on failure

Restart=no

[Install]

WantedBy=multi-user.target

4、node3上操作同上,直接复制即可　　

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