PgPool II Configuration

PgPool II Configuration

1. Open the file /etc/pgpool-II/pool_hba.conf and configure it just like you did in this section.

2. Now open /etc/pgpool-II/pgpool.conf and change the following settings to these values:
   (You can check what all the settings are here)

• backend_hostname0 = '192.168.1.1'
• backend_port0 = 5432
• backend_weight0 = 1
• backend_data_directory0 = '/var/lib/postgresql/9.2/main/'
• backend_flag0 = 'ALLOW_TO_FAILOVER'

Note: you need the above 5 lines for each of the PostgreSQL machines, so go ahead and repeat them for each missing machine. You have to change the number at the end of each setting name. So, for the second machine you can have backend_hostname1 and so on.

• master_slave_mode = on
• master_slave_sub_mode = 'stream'
• port = 5432 - Use the standard PostgreSQL port
• load_balance_mode = on
• health_check_period = 10 - in seconds, change this if you want different delays before initiating a PostgreSQL failover
• health_check_timeout = 5 - in seconds, should be smaller than the period
• use_watchdog = on
• delegate_IP = 192.168.1.111 - This is the virtual IP, you must choose one that isn't being used
• wd_hostname = '192.168.1.100' - This is the IP of this PgPool II server Remember that this setting must be different for each PgPool server, they point to each other
• wd_port = 9000
• if_up_cmd = 'ifconfig eth0:111 inet $_IP_$ netmask 255.255.255.0'
• if_down_cmd = 'ifconfig eth0:111 down'
• wd_interval = 3
• other_pgpool_hostname0 = '192.168.1.101'
• other_pgpool_port0 = 5432
• other_wd_port = 9000

- `white_function_list = 'pg_last_xlog_replay_location'` - `black_function_list = ''` > Since PgPool doesn't know if functions in your database write to the database or not, you have to set either a white list or a black list. [**They can't both be non-empty**](http://www.pgpool.net/docs/latest/pgpool-en.html#BLACK_FUNCTION_LIST)