unexpected authentication response

[itshikanov]

Hello, i'm got problem with authentication of exporter.

postgresql: 15
pgpool-II version 4.4.5 (nurikoboshi)
pgpool2_exporter-1.2.1.linux-amd64.tar.gz

I'm configure passthrough authentication in pgpool and try to use pgpool_exporter to get metrics. When i'm start exporter i'm got error.

~/pgpool_exporter/pgpool2_exporter-1.2.1.linux-amd64#

DATA_SOURCE_USER=test DATA_SOURCE_PASS=test DATA_SOURCE_URI="192.168.50.1:5430/test?sslmode=disable" ./pgpool2_exporter
ts=2023-12-21T08:41:04.767Z caller=pgpool2_exporter.go:231 level=error err="error connecting to Pgpool-II: pq: unexpected authentication response: 'R'"

This is my settings of pgpool

pool_hba.conf:

host  all             all             all            password

my pgpool.conf template

listen_addresses = '*'
port = 5430

ssl = false
ssl_key = 'path_to_file'
ssl_cert = 'path_to_file'

pid_file_name = '/tmp/pgpool.pid'

enable_pool_hba = true
allow_clear_text_frontend_auth = false

pool_passwd  = ''

connection_cache = off

connection_life_time = 5

load_balance_mode = on

# disable_load_balance_on_write = transaction

failover_on_backend_error = off

num_init_children = 500
max_pool = 1

sr_check_period = 0                                     # default = 0. Disable check of replica lag.

health_check_period = 0                                 # Default 0. We use haproxy. Do not check backend

backend_clustering_mode = 'streaming_replication'

backend_hostname0 = '127.0.0.1'                         # Host name or IP address to connect to for backend 0
backend_port0 = 5428                 # Port number for backend 0
backend_weight0 = 1                                     # Weight for backend 0 (only in load balancing mode)
#backend_data_directory0 = '/var/lib/postgresql/11/main'# Data directory for backend 0
backend_flag0 = 'ALWAYS_PRIMARY|DISALLOW_TO_FAILOVER'   # always primary  !

backend_hostname1 = '127.0.0.1'                         # Host name or IP address to connect to for backend 0
backend_port1 = 5429                # Port number for backend 1
backend_weight1 = 2                                     # Weight for backend 1 (only in load balancing mode)

backend_flag1 = 'DISALLOW_TO_FAILOVER'

auto_failback = off                                     # Streaming Replication Check needed(sr_check_period), and user and password
auto_failback_interval = 5

log_connections = off  # when enable and give load . got error child process with pid: was terminated by segmentation fault. And client disconected. BUG ?
log_disconnections = off
log_statement = off
log_per_node_statement = on
log_client_messages = off
log_error_verbosity = terse

Traffic is:

####
T 192.168.50.201:51180 -> 192.168.50.1:5430 [AP] #27
  ...^....user.test.datestyle.ISO, MDY.client_encoding.UTF8.database.test.extra_float_digits.2..                                                          
##
T 192.168.50.1:5430 -> 192.168.50.201:51180 [AP] #29
  R........                                                                                                                                               
##
T 192.168.50.201:51180 -> 192.168.50.1:5430 [AP] #31
  p....test.                                                                                                                                              
#
T 192.168.50.1:5430 -> 192.168.50.201:51180 [AP] #32
  R........SCRAM-SHA-256..                                                                                                                                
####

On string R........SCRAM-SHA-256.. fail occured

Postgresql command psql - work well while pgpool_exporter is failed

PGPASSWORD='test' psql -h 192.168.50.1 -U test -p 5430 -d test"

I'm found workaround
enable_pool_hba = false
allow_clear_text_frontend_auth = true

But this option add 3 line in log on every connection(that need not! You can reduce this lines to 1 by log_error_verbosity = terse option )

# [pgpool] 2023-12-13 15:56:27.159: child pid 687: HINT:  you can disable this behavior by setting allow_clear_text_frontend_auth to off
# [pgpool] 2023-12-13 15:56:27.332: psql pid 684: LOG:  using clear text authentication with frontend
# [pgpool] 2023-12-13 15:56:27.332: psql pid 684: DETAIL:  backend will still use SCRAM auth

SCRAM not used at all in this configuration.