I have Postgresql 13 database and Barman 2.7 deployed for backing it up. The Barman is deployed on separated server. Barman is using streaming backup and WAL streaming via pg_recievewal.
However the pg_wal directory become enormously large/not cleaned up
The replication slot reports that barman received the latest WAL, Barman shows no indication of issues on his side. I used the following query to find if the last WAL received by Barman:
SELECT slot_name,
lpad((pg_control_checkpoint()).timeline_id::text, 8, '0') ||
lpad(split_part(restart_lsn::text, '/', 1), 8, '0') ||
lpad(substr(split_part(restart_lsn::text, '/', 2), 1, 2), 8, '0')
AS wal_file
FROM pg_replication_slots;
The value reported by it, is the same as the value reported by SELECT pg_walfile_name(pg_current_wal_lsn());
After enabling archival with barman-wal-archive the pg_wal directory started cleaning up. If I understood correctly having archival is not mandatory when pg_recievewal is used.
Is my understanding correct? If so, then why are WAL archives piling up?
wal streaming require a barman user with replication privilege :
below is the related configuration file part
; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; PostgreSQL streaming connection string
; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; To be used by pg_basebackup for backup and pg_receivewal for WAL streaming
; NOTE: streaming_barman is a regular user with REPLICATION privilege
streaming_conninfo = host=$DataBaseHost user=streaming_barman
; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; WAL streaming settings (via pg_receivewal)
; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
streaming_archiver = on
slot_name = barman
create_slot = auto
;streaming_archiver_name = barman_receive_wal
;streaming_archiver_batch_size = 50
you can create the related user in postgres using :
sudo -u postgres createuser -P --replication streaming_barman
and test the replication from barman host using
psql -U streaming_barman -h $yourDbIp -c "IDENTIFY_SYSTEM" replication=1
after having reported the related user password in a local .pgpass file.