Physical PostgreSQL Backup using BARMAN

In the previous blog, we have demonstrated Install & Configured barman tool in Backup Server Click here to read more.
In this blog, we will use barman tool to take database backups.

List available servers: Use command barman list-server to get the list configured server in barman.

-bash-4.2$ barman list-server
test-machine02 - test-machine02 backup config
-bash-4.2$

Show configured parameters: Use command barman show-server to list down all configured parameters for the specified server.

-bash-4.2$ barman show-server test-machine02
Server test-machine02:
        active: True
        archive_command: test ! -f barman@test-machine01:/var/lib/barman/test-machine02/incoming/%f && rsync -a %p barman@test-machine01:/var/lib/barman/test-machine02/incoming/%f
        archive_mode: on
        archive_timeout: 21600
        archived_count: 67
        archiver: True
        archiver_batch_size: 0
        backup_directory: /var/lib/barman/test-machine02
        backup_method: rsync
        backup_options: BackupOptions(['concurrent_backup'])
        bandwidth_limit: None
        barman_home: /var/lib/barman
        barman_lock_directory: /var/lib/barman
        basebackup_retry_sleep: 30
        basebackup_retry_times: 3
        basebackups_directory: /var/lib/barman/test-machine02/base
        check_timeout: 30
        checkpoint_timeout: 300
        compression: gzip
        config_file: /var/lib/pgsql/13/data/postgresql.conf
        conninfo: host=test-machine02 user=barman port=5432 dbname=postgres password=*REDACTED* create_slot: manual

Check server configuration: Use command barman check to confirm all server configuration is OK.

-bash-4.2$ barman check test-machine02
Server test-machine02:
        PostgreSQL: OK
        superuser or standard user with backup privileges: OK
        wal_level: OK
        directories: OK
        retention policy settings: OK
        backup maximum age: OK (no last_backup_maximum_age provided)
        compression settings: OK
        failed backups: OK (there are 0 failed backups)
        minimum redundancy requirements: OK (have 3 backups, expected at least 0)
        ssh: OK (PostgreSQL server)
        systemid coherence: OK
        archive_mode: OK
        archive_command: OK
        continuous archiving: OK
        archiver errors: OK
-bash-4.2$

Help Command: Use option –help to get all available options for barman.

-bash-4.2$ barman --help
usage: barman [-h] [-v] [-c CONFIG] [--color {never,always,auto}]
              [--log-level {NOTSET,DEBUG,INFO,WARNING,ERROR,CRITICAL}] [-q]
              [-d] [-f {json,console}]

              {archive-wal,backup,check,check-backup,cron,delete,diagnose,get-wal,list-backup,list-files,list-server,put-wal,rebuild-xlogdb,receive-wal,recover,show-backup,show-server,replication-status,status,switch-wal,switch-xlog,sync-info,sync-backup,sync-wals}
              ...

positional arguments:
  {archive-wal,backup,check,check-backup,cron,delete,diagnose,get-wal,list-backup,list-files,list-server,put-wal,rebuild-xlogdb,receive-wal,recover,show-backup,show-server,replication-status,status,switch-wal,switch-xlog,sync-info,sync-backup,sync-wals}
    archive-wal         Execute maintenance operations on WAL files for a
                        given server. This command processes any incoming WAL
                        files for the server and archives them along the
                        catalogue.
    backup              Perform a full backup for the given server (supports
                        'all')

Help for Specific Command: Use barman <command> –help to get full available options that specific command.

-bash-4.2$ barman backup --help
usage: barman backup [-h] [--immediate-checkpoint] [--no-immediate-checkpoint]
                     [--reuse-backup [{copy,link,off}]]
                     [--retry-times RETRY_TIMES] [--retry-sleep RETRY_SLEEP]
                     [--no-retry] [--jobs NJOBS] [--bwlimit KBPS] [--wait]
                     [--wait-timeout TIMEOUT]
                     server_name [server_name ...]

    Perform a full backup for the given server (supports 'all')


positional arguments:
  server_name           specifies the server names for the backup command
                        ('all' will show all available servers)

optional arguments:
  -h, --help            show this help message and exit
  --immediate-checkpoint
                        forces the initial checkpoint to be done as quickly as
                        possible

Full Database Backup: Use command barman backup to take full database backup of specific Server.

-bash-4.2$ barman backup test-machine02
Starting backup using rsync-concurrent method for server test-machine02 in /var/lib/barman/test-machine02/base/20210622T153402
Backup start at LSN: 0/32000028 (000000010000000000000032, 00000028)
This is the first backup for server test-machine02
WAL segments preceding the current backup have been found:
        000000010000000000000030 from server test-machine02 has been removed
        000000010000000000000030.00000060.backup from server test-machine02 has been removed
Starting backup copy via rsync/SSH for 20210622T153402
Copy done (time: 3 seconds)
This is the first backup for server test-machine02
Asking PostgreSQL server to finalize the backup.
Backup size: 46.8 MiB. Actual size on disk: 46.8 MiB (-0.00% deduplication ratio).
Backup end at LSN: 0/32000138 (000000010000000000000032, 00000138)
Backup completed (start time: 2021-06-22 15:34:03.046194, elapsed time: 6 seconds)
Processing xlog segments from file archival for test-machine02
        000000010000000000000031
        000000010000000000000032
        000000010000000000000032.00000028.backup
-bash-4.2$

Full Database Backup: You can also take full database backup using the below command as well.

-bash-4.2$ barman backup test-machine02 --reuse-backup=off
Starting backup using rsync-concurrent method for server test-machine02 in /var/lib/barman/test-machine02/base/20210623T143656
Backup start at LSN: 0/34000028 (000000010000000000000034, 00000028)
Starting backup copy via rsync/SSH for 20210623T143656
Copy done (time: 3 seconds)
Asking PostgreSQL server to finalize the backup.
Backup size: 46.8 MiB
Backup end at LSN: 0/34000100 (000000010000000000000034, 00000100)
Backup completed (start time: 2021-06-23 14:36:56.282179, elapsed time: 7 seconds)
Processing xlog segments from file archival for test-machine02
        000000010000000000000034
        000000010000000000000034.00000028.backup
-bash-4.2$
-bash-4.2$

Incremental Database Backup: Use option –reuse-backup=link along with barman backup command to take incremental backup of the database.

-bash-4.2$ barman backup test-machine02 --reuse-backup=link 
Starting backup using rsync-concurrent method for server test-machine02 in /var/lib/barman/test-machine02/base/20210623T154948
Backup start at LSN: 0/36000028 (000000010000000000000036, 00000028)
Starting backup copy via rsync/SSH for 20210623T154948
Copy done (time: 1 second)
Asking PostgreSQL server to finalize the backup.
Backup size: 46.8 MiB. Actual size on disk: 9.8 KiB (-99.98% deduplication ratio).
Backup end at LSN: 0/36000100 (000000010000000000000036, 00000100)
Backup completed (start time: 2021-06-23 15:49:49.106786, elapsed time: 6 seconds)
Processing xlog segments from file archival for test-machine02
        000000010000000000000035
        000000010000000000000036
        000000010000000000000036.00000028.backup
-bash-4.2$
-bash-4.2$

List available backup: Use command barman list-backup to list all available backups of the specific server.

-bash-4.2$ barman list-backup test-machine02
test-machine02 20210623T154948 - Wed Jun 23 15:49:57 2021 - Size: 46.9 MiB - WAL Size: 0 B (tablespaces: myts01:/u01/psql_tbls, myts02:/u01/psql2_tbls)
test-machine02 20210623T143656 - Wed Jun 23 14:37:06 2021 - Size: 46.9 MiB - WAL Size: 32.3 KiB (tablespaces: myts01:/u01/psql_tbls, myts02:/u01/psql2_tbls)
test-machine02 20210622T153402 - Tue Jun 22 15:34:12 2021 - Size: 46.9 MiB - WAL Size: 32.3 KiB (tablespaces: myts01:/u01/psql_tbls, myts02:/u01/psql2_tbls)
test-machine02 20210622T153129 - FAILED
-bash-4.2$

Detailed Information of specific Backup: Use command barman show-backup to get detailed information of specific backup.

-bash-4.2$ barman show-backup test-machine02 20210623T154948
Backup 20210623T154948:
  Server Name            : test-machine02
  System Id              : 6955437016975533153
  Status                 : DONE
  PostgreSQL Version     : 130002
  PGDATA directory       : /var/lib/pgsql/13/data
  Tablespaces:
    myts01: /u01/psql_tbls (oid: 23701)
    myts02: /u01/psql2_tbls (oid: 23704)

  Base backup information:
    Disk usage           : 46.8 MiB (46.9 MiB with WALs)
    Incremental size     : 9.8 KiB (-99.98%)
    Timeline             : 1
    Begin WAL            : 000000010000000000000036
    End WAL              : 000000010000000000000036
    WAL number           : 1
    WAL compression ratio: 99.90%
    Begin time           : 2021-06-23 15:49:52.521603+03:00
    End time             : 2021-06-23 15:49:57.173958+03:00
    Copy time            : 1 second + 1 second startup
    Estimated throughput : 5.3 KiB/s
    Begin Offset         : 40
    End Offset           : 256
    Begin LSN           : 0/36000028
    End LSN             : 0/36000100

  WAL information:
    No of files          : 0
    Disk usage           : 0 B
    Last available       : 000000010000000000000036

  Catalog information:
    Retention Policy     : not enforced
    Previous Backup      : 20210623T143656
    Next Backup          : - (this is the latest base backup)
-bash-4.2$

WAL only Backup: Use command barman archive-wal to take the only backup of WAL Files.

-bash-4.2$ barman archive-wal test-machine02 
Processing xlog segments from file archival for test-machine02
        000000010000000000000037
        000000010000000000000038
-bash-4.2$

Delete backup: Use command barman delete to delete specific backup files.

-bash-4.2$ barman delete test-machine02 20210622T153129
Deleting backup 20210622T153129 for server test-machine02
Delete associated WAL segments:
Deleted backup 20210622T153129 (start time: Wed Jun 23 17:12:08 2021, elapsed time: less than one second)
-bash-4.2$

This document is just for learning purpose and always validate in the LAB environment first before applying in the LIVE environment.

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BACKUP, BARMAN, POSTGRESQL

DBsGuru