I am following this example from pgpool official docs

however after the failed master recoverd and in standby mode it wont get any replication from the new master.

here is the pgpool.conf for all nodes:

backend_clustering_mode = 'streaming_replication'
listen_addresses = '*'
pcp_listen_addresses = '*'
port = 9999
enable_pool_hba = on

sr_check_user = 'pgpool'
sr_check_password = ''

health_check_period = 5
health_check_timeout = 30
health_check_user = 'pgpool'
health_check_password = ''
health_check_max_retries = 3

# backend connection settings
backend_hostname0 = 'db2'
backend_application_name0 = 'db01'
backend_port0 = 5432
backend_weight0 = 1
backend_data_directory0 = '/var/lib/pgsql/16/data'
backend_flag0 = 'ALLOW_TO_FAILOVER'

backend_hostname1 = 'db2'
backend_application_name1 = 'db02'
backend_port1 = 5432
backend_weight1 = 1
backend_data_directory1 = '/var/lib/pgsql/16/data'
backend_flag1 = 'ALLOW_TO_FAILOVER'

backend_hostname2 = 'db3'
backend_application_name2 = 'db03'
backend_port2 = 5432
backend_weight2 = 1
backend_data_directory2 = '/var/lib/pgsql/16/data'
backend_flag2 = 'ALLOW_TO_FAILOVER'

#logging
log_destination = 'stderr'
logging_collector = on
log_directory = '/var/log/pgpool_log'
log_filename = 'pgpool-%Y-%m-%d_%H%M%S.log'
log_truncate_on_rotation = on
log_rotation_age = 1d
log_rotation_size = 10MB

#debugging
log_statement = on
log_per_node_statement = on

#fail over scripts
failover_command = '/etc/pgpool-II/failover.sh %d %h %p %D %m %H %M %P %r %R %N %S'
follow_primary_command = '/etc/pgpool-II/follow_primary.sh %d %h %p %D %m %H %M %P %r %R'

#recovery
recovery_user = 'postgres'
recovery_password = ''
recovery_1st_stage_command = 'recovery_1st_stage'

#watchdog
use_watchdog = on
delegate_ip = '192.168.122.20'

wd_lifecheck_method = 'heartbeat'
wd_interval = 10

if_cmd_path = '/sbin'
arping_path = '/usr/sbin'

if_up_cmd = '/usr/bin/sudo /sbin/ip addr add $_IP_$/24 dev enp1s0 label enp1s0:0'
if_down_cmd = '/usr/bin/sudo /sbin/ip addr del $_IP_$/24 dev enp1s0'
arping_cmd = '/usr/bin/sudo /usr/sbin/arping -U $_IP_$ -w 1 -I enp1s0'

hostname0 = 'db01.nomadesk.org'
wd_port0 = 9000
pgpool_port0 = 9999

hostname1 = 'db02.nomadesk.org'
wd_port1 = 9000
pgpool_port1 = 9999

hostname2 = 'db03.nomadesk.org'
wd_port2 = 9000
pgpool_port2 = 9999

wd_heartbeat_keepalive = 2
wd_heartbeat_deadtime = 30

heartbeat_hostname0 = 'db1'
heartbeat_port0 = 9694
heartbeat_device0 = ''
heartbeat_hostname1 = 'db2'
heartbeat_port1 = 9694
heartbeat_device1 = ''
heartbeat_hostname2 = 'db3'
heartbeat_port2 = 9694
heartbeat_device2 = ''

wd_escalation_command = '/etc/pgpool-II/escalation.sh'

and all the scripts are the sample scripts provided by the example.

the only thing I added was psotgres-ctl.sh

cat << EOF > /etc/pgpool-II/postgres-ctl.sh
#!/bin/bash

# Usage
#
# $1: can be start/stop or restart
# $2: postgresql version

systemctl $1 postgresql-$2
EOF
chmod +x /etc/pgpool-II/postgres-ctl.sh

that is used instead of pg_ctl in follow_primary.sh for example

sudo /etc/pgpool-II/postgres-ctl.sh start 16
#instead of
${PGHOME}/bin/pg_ctl -l /dev/null -w -D ${NODE_PGDATA} start

because pg_ctl would not find the postman.pid so using systemd fixed the problem.

psql -h vip -p 9999 -U pgpool postgres -c "show pool_nodes"
| node_id | hostname | port | status | pg_status | lb_weight |  role   | pg_role | select_cnt | load_balance_node | replication_delay | replication_state | replication_sync_state | last_status_change    |
|---------|----------|------|--------|-----------|-----------|---------|---------|------------|-------------------|-------------------|-------------------|------------------------|-----------------------|
| 0       | server1  | 5432 | down   | down      | 0.333333  | standby | unknown | 0          | false             | 0                 |                   |                        | 2023-11-10 17:05:40   |
| 1       | server2  | 5432 | up     | up        | 0.333333  | primary | primary | 0          | false             | 0                 |                   |                        | 2023-11-10 17:05:40   |
| 2       | server3  | 5432 | up     | up        | 0.333333  | standby | standby | 0          | true              | 0                 | streaming         | async                  | 2023-11-10 17:05:51   |