tldr/pages/common/pg_combinebackup.md

pg_combinebackup

Reconstruct a full (synthetic) PostgreSQL backup from an incremental backup chain. When specifying multiple backups order them from oldest to newest. More information: https://www.postgresql.org/docs/current/app-pgcombinebackup.html.

• Combine a full and incremental backup into one synthetic full backup:

pg_combinebackup {{path/to/full_backup}} {{path/to/incremental_backup}} {{[-o|--output]}} {{path/to/output_directory}}

• Perform a dry run to show what would be done, without creating files:

pg_combinebackup {{[-n|--dry-run]}} {{path/to/full_backup}} {{path/to/incremental_backup}} {{[-o|--output]}} {{path/to/output_directory}}

• Use hard links instead of copying files (faster, same filesystem required):

pg_combinebackup {{[-k|--link]}} {{path/to/full_backup}} {{path/to/incremental_backup}} {{[-o|--output]}} {{path/to/output_directory}}

• Use file cloning (reflinks) for efficient copy if supported:

pg_combinebackup --clone {{path/to/full_backup}} {{path/to/incremental_backup}} {{[-o|--output]}} {{path/to/output_directory}}

• Use the copy_file_range system call for efficient copying:

pg_combinebackup --copy-file-range {{path/to/full_backup}} {{path/to/incremental_backup}} {{[-o|--output]}} {{path/to/output_directory}}

• Relocate a tablespace during reconstruction:

pg_combinebackup {{path/to/backup1 path/to/backup2 ...}} {{[-T|--tablespace-mapping]}} /{{path/to/old_tablespace}}=/{{path/to/new_tablespace}} {{[-o|--output]}} {{path/to/output_directory}}

• Disable fsync for faster but unsafe writes (testing only):

pg_combinebackup {{[-N|--no-sync]}} {{path/to/backup1 path/to/backup2 ...}} {{[-o|--output]}} {{path/to/output_directory}}

• Show detailed debug output:

pg_combinebackup {{[-d|--debug]}} {{path/to/backup1 path/to/backup2 ...}} {{[-o|--output]}} {{path/to/output_directory}}