PostgreSQL: Database replication

##src: https://www.digitalocean.com/community/tutorials/how-to-set-up-master-slave-replication-on-postgresql-on-an-ubuntu-12-04-vps#configure-the-master-server ############## Master: psql -c "CREATE USER rep REPLICATION LOGIN CONNECTION LIMIT 1 ENCRYPTED PASSWORD 'yourpassword';" #//at file /etc/postgresql/9.5/main/pg_hba.conf host replication rep IP_address_of_slave/32 md5 #//at file /etc/postgresql/9.5/main/postgresql.conf listen_addresses = 'localhost,IP_address_of_THIS_host' wal_level = 'hot_standby' archive_mode = on archive_command = 'cd .' max_wal_senders = 1 hot_standby = on service postgresql restart ############### Slave: service postgresql stop #//at file /etc/postgresql/9.5/main/pg_hba.conf host replication rep IP_address_of_master/32 md5 #//at file /etc/postgresql/9.5/main/postgresql.conf listen_addresses = 'localhost,IP_address_of_THIS_host' wal_level = 'hot_standby' archive_mode = on archive_command = 'cd .' max_wal_senders = 1 hot_standby = on ################## Master: psql -c "select pg_start_backup('initial_backup');" rsync -cva --inplace --exclude=*pg_xlog* /var/lib/postgresql/9.5/main/ slave_IP_address:/var/lib/postgresql/9.5/main/ psql -c "select pg_stop_backup();" ################### Slave: cd /var/lib/postgresql/9.5/main/recovery.conf standby_mode = 'on' primary_conninfo = 'host=master_IP_address port=5432 user=rep password=yourpassword' trigger_file = '/tmp/postgresql.trigger.5432' ##When we want to set SLAVE db to Master (because of original MASTER fail) creating this file is enough. With the existence of this file db will act like MASTER. service postgresql start ## we check if no problem: less /var/log/postgresql/postgresql-9.5-main.log