Multiple Repositories
A key feature of the v2.33 pgBackrest release is support for multiple repositories. This lets you define different behavior for different backup repositories. As an example, you could have a local repository for fast restore that had short retention period (to save space) paired with a remote repository which is larger for cold storage.
This feature introduces a new --repo option which can be used to set the repository the command should apply to. All repo*- options are indexed to enable configuring multiple repositories.
In this section, we will set up a demo cluster (using EDB Postgres Advanced Server version 13 on CentOS 7) to demonstrate how this new feature impacts each pgBackRest command.
Configuration
It must be noted that in this demo, we will set up two local repositories on our database host. For production purposes, it is recommended to store each repository on separate storage, and configure at least one remote repository.
[global] # repository details repo1-path=/var/lib/edb/as13/backups/repo1 repo1-retention-full=1 repo2-path=/var/lib/edb/as13/backups/repo2 repo2-retention-full=1 # general options process-max=2 log-level-console=info log-level-file=debug start-fast=y delta=y [demo] pg1-path=/var/lib/edb/as13/data pg1-user=enterprisedb pg1-port=5444
For safety reasons, the --repo option can't be defined in the configuration file or a warning will be triggered: WARN: configuration file contains command-line only option 'repo'. If there is more than one repository configured and the --repo option is not specified for a command, the repository with the highest priority order (e.g. repo1 then repo2) will be chosen by default.
The --repo option is not required when only repo1 is configured to maintain backward compatibility. However, when a single repository is configured, it is recommended to use repo1 in the configuration.
Initialization
Stanza Create Command
The stanza-create command will automatically operate on all configured repositories:
$ pgbackrest --stanza=demo stanza-create P00 INFO: stanza-create for stanza 'demo' on repo1 P00 INFO: stanza-create for stanza 'demo' on repo2
Check Command
The check command will trigger a new WAL segment to be archived and try to push it to all defined repositories:
$ pgbackrest --stanza=demo check P00 INFO: check repo1 configuration (primary) P00 INFO: check repo2 configuration (primary) P00 INFO: check repo1 archive for WAL (primary) P00 INFO: WAL segment ... successfully archived to '...' on repo1 P00 INFO: check repo2 archive for WAL (primary) P00 INFO: WAL segment ... successfully archived to '...' on repo2
Archive Push Command
The archive-push command will always archive WALs in all configured repositories. Backups will need to be scheduled individually for each repository. In most cases, this is desirable since backup types and retention could vary per repository.
The archive_command can still be defined as usual:
$ psql -d postgres -c "show archive_command;" archive_command ------------------------------------------ pgbackrest --stanza=demo archive-push %p (1 row)
Here is a DEBUG extract of the PostgreSQL logs showing the archive-push activity:
...
P00 DEBUG: storage/storage::storageNewWrite: => {
type: posix, name: {"/var/lib/edb/as13/backups/repo1/archive/demo/13-1/0000000100000000/
000000010000000000000005-be9a61a800934879842fa647b0d50385f44e0228.gz"},
modeFile: 0640, modePath: 0750, createPath: true, syncFile: true, syncPath: true, atomic: true}
...
P00 DEBUG: storage/storage::storageNewWrite: => {
type: posix, name: {"/var/lib/edb/as13/backups/repo2/archive/demo/13-1/0000000100000000/
000000010000000000000005-be9a61a800934879842fa647b0d50385f44e0228.gz"},
modeFile: 0640, modePath: 0750, createPath: true, syncFile: true, syncPath: true, atomic: true}
...
P00 INFO: pushed WAL file '000000010000000000000005' to the archiveThe archive-push command will try to push the WAL archive to all reachable repositories. The idea is to archive to as many repositories as possible even if we still need to throw an error to PostgreSQL to prevent it from removing the WAL file.
P00 INFO: archive-push command begin: [pg_wal/000000010000000000000006] ...
...
P00 INFO: archive-push command begin: [pg_wal/000000010000000000000007] ...
ERROR: [104]: archive-push command encountered error(s):
repo2: [PathOpenError] unable to list file info for path '...': [13] Permission denied
P00 INFO: archive-push command end: aborted with exception [104]
DETAIL: The failed archive command was: pgbackrest --stanza=demo archive-push pg_wal/000000010000000000000007
WARNING: archiving write-ahead log file "000000010000000000000007" failed too many times, will try again laterThe PostgreSQL archiver process should then report an error:
$ ps -o pid,cmd fx |grep archiver 4440 \_ postgres: archiver failed on 000000010000000000000007
The next WAL segments should not then be archived:
$ psql -d postgres -c "SELECT pg_create_restore_point('generate some activity'); SELECT pg_switch_wal();" pg_switch_wal --------------- 0/80001C8 (1 row) $ ls as13/data/pg_wal/archive_status/ |grep ".ready" 000000010000000000000007.ready 000000010000000000000008.ready
This becomes very handy by adding archive-async=y to the configuration in order to use asynchronous archiving processes within pgBackRest itself. Even if PostgreSQL archiver process is still stuck, the archives will reach the working repositories:
$ $ ls /var/lib/edb/as13/backups/repo1/archive/demo/13-1/0000000100000000/ 000000010000000000000005-be9a61a800934879842fa647b0d50385f44e0228.gz 000000010000000000000006-7108296955e1208c93447dcfc5712ce59af97907.gz 000000010000000000000007-f1b6fcdd23e96a19a7a89dc92613674c2316aa49.gz 000000010000000000000008-791c44d39ef772d58e51d64c8e3589231d3916a4.gz 000000010000000000000009-47241214eb3fd5e693eed778caa7b304a778ecc2.gz $ ls /var/lib/edb/as13/backups/repo2/archive/demo/13-1/0000000100000000/ 000000010000000000000005-be9a61a800934879842fa647b0d50385f44e0228.gz 000000010000000000000006-7108296955e1208c93447dcfc5712ce59af97907.gz
Let us unblock the archiver process (and remove asynchronous archiving) before going further:
$ $ ps -o pid,cmd fx |grep archiver 4440 \_ postgres: archiver last was 00000001000000000000000
Backups
Backup Command
Let us take a few backups:
$ pgbackrest backup --stanza=demo --type=full P00 INFO: backup command begin ... P00 INFO: repo option not specified, defaulting to repo1 P00 INFO: execute non-exclusive pg_start_backup(): backup begins after the requested immediate checkpoint completes P00 INFO: backup start archive = 00000001000000000000000C, lsn = 0/C000060 P00 INFO: full backup size = 50.4MB P00 INFO: execute non-exclusive pg_stop_backup() and wait for all WAL segments to archive P00 INFO: backup stop archive = 00000001000000000000000C, lsn = 0/C000138 P00 INFO: check archive for segment(s) 00000001000000000000000C:00000001000000000000000C P00 INFO: new backup label = 20210419-142212F P00 INFO: backup command end: completed successfully $ pgbackrest backup --stanza=demo --type=full --repo=2 P00 INFO: backup command begin ... P00 INFO: execute non-exclusive pg_start_backup(): backup begins after the requested immediate checkpoint completes P00 INFO: backup start archive = 00000001000000000000000E, lsn = 0/E000028 P00 INFO: full backup size = 50.5MB P00 INFO: execute non-exclusive pg_stop_backup() and wait for all WAL segments to archive P00 INFO: backup stop archive = 00000001000000000000000E, lsn = 0/E000138 P00 INFO: check archive for segment(s) 00000001000000000000000E:00000001000000000000000E P00 INFO: new backup label = 20210419-142414F P00 INFO: backup command end: completed successfully $ pgbackrest backup --stanza=demo --type=incr --repo=1 P00 INFO: backup command begin ... P00 INFO: last backup label = 20210419-142212F, version = ... P00 INFO: execute non-exclusive pg_start_backup(): backup begins after the requested immediate checkpoint completes P00 INFO: backup start archive = 000000010000000000000010, lsn = 0/10000028 P00 INFO: incr backup size = 50.5MB P00 INFO: execute non-exclusive pg_stop_backup() and wait for all WAL segments to archive P00 INFO: backup stop archive = 000000010000000000000010, lsn = 0/10000100 P00 INFO: check archive for segment(s) 000000010000000000000010:000000010000000000000010 P00 INFO: new backup label = 20210419-142212F_20210419-142502I P00 INFO: backup command end: completed successfully $ pgbackrest backup --stanza=demo --type=incr --repo=2 P00 INFO: backup command begin ... P00 INFO: last backup label = 20210419-142414F, version = ... P00 INFO: execute non-exclusive pg_start_backup(): backup begins after the requested immediate checkpoint completes P00 INFO: backup start archive = 000000010000000000000012, lsn = 0/12000028 P00 INFO: incr backup size = 50.6MB P00 INFO: execute non-exclusive pg_stop_backup() and wait for all WAL segments to archive P00 INFO: backup stop archive = 000000010000000000000012, lsn = 0/12000100 P00 INFO: check archive for segment(s) 000000010000000000000012:000000010000000000000012 P00 INFO: new backup label = 20210419-142414F_20210419-142556I P00 INFO: backup command end: completed successfully
Here, we alternated full and incr backups in each repository.
Info Command
$ pgbackrest info --stanza=demo stanza: demo status: ok cipher: none db (current) wal archive min/max (13): 000000010000000000000002/000000010000000000000012 full backup: 20210419-142212F timestamp start/stop: 2021-04-19 14:22:12 / 2021-04-19 14:22:26 wal start/stop: 00000001000000000000000C / 00000001000000000000000C database size: 50.4MB, database backup size: 50.4MB repo1: backup set size: 8MB, backup size: 8MB full backup: 20210419-142414F timestamp start/stop: 2021-04-19 14:24:14 / 2021-04-19 14:24:26 wal start/stop: 00000001000000000000000E / 00000001000000000000000E database size: 50.5MB, database backup size: 50.5MB repo2: backup set size: 8MB, backup size: 8MB incr backup: 20210419-142212F_20210419-142502I timestamp start/stop: 2021-04-19 14:25:02 / 2021-04-19 14:25:04 wal start/stop: 000000010000000000000010 / 000000010000000000000010 database size: 50.5MB, database backup size: 613.4KB repo1: backup set size: 8MB, backup size: 26.3KB backup reference list: 20210419-142212F incr backup: 20210419-142414F_20210419-142556I timestamp start/stop: 2021-04-19 14:25:56 / 2021-04-19 14:25:57 wal start/stop: 000000010000000000000012 / 000000010000000000000012 database size: 50.6MB, database backup size: 661.5KB repo2: backup set size: 8MB, backup size: 28KB backup reference list: 20210419-142414F
The default order will sort backups by dates mixing the repositories. It might be confusing to find the backups depending on each other.
We can then split this view per repository:
$ pgbackrest info --stanza=demo --repo=1 stanza: demo status: ok cipher: none db (current) wal archive min/max (13): 00000001000000000000000C/000000010000000000000012 full backup: 20210419-142212F timestamp start/stop: 2021-04-19 14:22:12 / 2021-04-19 14:22:26 wal start/stop: 00000001000000000000000C / 00000001000000000000000C database size: 50.4MB, database backup size: 50.4MB repo1: backup set size: 8MB, backup size: 8MB incr backup: 20210419-142212F_20210419-142502I timestamp start/stop: 2021-04-19 14:25:02 / 2021-04-19 14:25:04 wal start/stop: 000000010000000000000010 / 000000010000000000000010 database size: 50.5MB, database backup size: 613.4KB repo1: backup set size: 8MB, backup size: 26.3KB backup reference list: 20210419-142212F $ pgbackrest info --stanza=demo --repo=2 stanza: demo status: ok cipher: none db (current) wal archive min/max (13): 00000001000000000000000E/000000010000000000000012 full backup: 20210419-142414F timestamp start/stop: 2021-04-19 14:24:14 / 2021-04-19 14:24:26 wal start/stop: 00000001000000000000000E / 00000001000000000000000E database size: 50.5MB, database backup size: 50.5MB repo2: backup set size: 8MB, backup size: 8MB incr backup: 20210419-142414F_20210419-142556I timestamp start/stop: 2021-04-19 14:25:56 / 2021-04-19 14:25:57 wal start/stop: 000000010000000000000012 / 000000010000000000000012 database size: 50.6MB, database backup size: 661.5KB repo2: backup set size: 8MB, backup size: 28KB backup reference list: 20210419-142414F
The 'wal archive min/max' shows the minimum and maximum WAL currently stored in the archive and, in the case of multiple repositories, will be reported across all repositories unless the --repo option is set. There may be gaps due to archive retention policies or other reasons.
Let us break the first repository by removing its content:
$ pgbackrest --stanza=demo stanza-delete --repo=1 --force P00 INFO: stanza-delete command end: completed successfully $ pgbackrest --stanza=demo stanza-create P00 INFO: stanza-create for stanza 'demo' on repo1 P00 INFO: stanza-create for stanza 'demo' on repo2 P00 INFO: stanza 'demo' already exists on repo2 and is valid P00 INFO: stanza-create command end: completed successfully
If multiple repositories are configured, then a status of mixed indicates that the stanza is not in a healthy state for one or more of the repositories. In this case, the state of the stanza will be detailed in additional lines per repository.
$ pgbackrest info --stanza=demo stanza: demo status: mixed repo1: error (no valid backups) repo2: ok cipher: none db (current) wal archive min/max (13): 00000001000000000000000E/000000010000000000000012 full backup: 20210419-142414F timestamp start/stop: 2021-04-19 14:24:14 / 2021-04-19 14:24:26 wal start/stop: 00000001000000000000000E / 00000001000000000000000E database size: 50.5MB, database backup size: 50.5MB repo2: backup set size: 8MB, backup size: 8MB incr backup: 20210419-142414F_20210419-142556I timestamp start/stop: 2021-04-19 14:25:56 / 2021-04-19 14:25:57 wal start/stop: 000000010000000000000012 / 000000010000000000000012 database size: 50.6MB, database backup size: 661.5KB repo2: backup set size: 8MB, backup size: 28KB backup reference list: 20210419-142414F
This state can be resolved by taking a new backup:
$ pgbackrest backup --stanza=demo --type=full --repo=1 P00 INFO: backup command begin ... P00 INFO: execute non-exclusive pg_start_backup(): backup begins after the requested immediate checkpoint completes P00 INFO: backup start archive = 000000010000000000000014, lsn = 0/14000028 P00 INFO: full backup size = 50.6MB P00 INFO: execute non-exclusive pg_stop_backup() and wait for all WAL segments to archive P00 INFO: backup stop archive = 000000010000000000000014, lsn = 0/14000138 P00 INFO: check archive for segment(s) 000000010000000000000014:000000010000000000000014 P00 INFO: new backup label = 20210419-143400F P00 INFO: backup command end: completed successfully
Restore
Let us initiate a situation with some data, backups and restore point:
$ createdb test $ psql -d test -c "CREATE TABLE t1(id int);" CREATE TABLE $ psql -d test -c "INSERT INTO t1 VALUES (1);" INSERT 0 1 $ pgbackrest backup --stanza=demo --type=full --repo=1 P00 INFO: backup command begin ... P00 INFO: execute non-exclusive pg_start_backup(): backup begins after the requested immediate checkpoint completes P00 INFO: backup start archive = 000000010000000000000016, lsn = 0/16000028 P00 INFO: full backup size = 63.0MB P00 INFO: execute non-exclusive pg_stop_backup() and wait for all WAL segments to archive P00 INFO: backup stop archive = 000000010000000000000016, lsn = 0/16000138 P00 INFO: check archive for segment(s) 000000010000000000000016:000000010000000000000016 P00 INFO: new backup label = 20210419-143643F P00 INFO: backup command end: completed successfully P00 INFO: expire command begin ... P00 INFO: repo1: expire full backup 20210419-143400F P00 INFO: repo1: remove expired backup 20210419-143400F P00 INFO: expire command end: completed successfully $ psql -d test -c "INSERT INTO t1 VALUES (2);" INSERT 0 1 $ pgbackrest backup --stanza=demo --type=full --repo=2 P00 INFO: backup command begin ... P00 INFO: execute non-exclusive pg_start_backup(): backup begins after the requested immediate checkpoint completes P00 INFO: backup start archive = 000000010000000000000018, lsn = 0/18000028 P00 INFO: full backup size = 63MB P00 INFO: execute non-exclusive pg_stop_backup() and wait for all WAL segments to archive P00 INFO: backup stop archive = 000000010000000000000018, lsn = 0/18000138 P00 INFO: check archive for segment(s) 000000010000000000000018:000000010000000000000018 P00 INFO: new backup label = 20210419-143749F P00 INFO: backup command end: completed successfully P00 INFO: expire command begin ... P00 INFO: repo2: expire full backup set 20210419-142414F, 20210419-142414F_20210419-142556I P00 INFO: repo2: remove expired backup 20210419-142414F_20210419-142556I P00 INFO: repo2: remove expired backup 20210419-142414F P00 INFO: expire command end: completed successfully $ psql -d postgres -c "select pg_create_restore_point('RP1');" pg_create_restore_point ------------------------- 0/190000C8 (1 row) $ psql -d postgres -Atc "select current_timestamp,current_setting('datestyle'),txid_current();" 19-APR-21 14:38:55.313716 +00:00|Redwood, SHOW_TIME|1183 $ psql -d test -c "INSERT INTO t1 VALUES (3); SELECT pg_switch_wal();" pg_switch_wal --------------- 0/19000238 (1 row) $ pgbackrest info --stanza=demo stanza: demo status: ok cipher: none db (current) wal archive min/max (13): 000000010000000000000016/000000010000000000000019 full backup: 20210419-143643F timestamp start/stop: 2021-04-19 14:36:43 / 2021-04-19 14:37:01 wal start/stop: 000000010000000000000016 / 000000010000000000000016 database size: 63.0MB, database backup size: 63.0MB repo1: backup set size: 10MB, backup size: 10MB full backup: 20210419-143749F timestamp start/stop: 2021-04-19 14:37:49 / 2021-04-19 14:38:03 wal start/stop: 000000010000000000000018 / 000000010000000000000018 database size: 63MB, database backup size: 63MB repo2: backup set size: 10MB, backup size: 10MB
As you can see in the example above, the backup command automatically triggered the expire command on the repository when we created a backup. Since this command is operating on one repository only, it would not expire anything in the other repositories until the backup or expire command is run for that repository.
Since the default retention policy is based on a number of backups, it is expected that only new backups are affecting the backups and archives to expire.
Restore Command
The restore command automatically defaults to selecting the latest backup from the first repository where backups exist. The order in which the repositories are checked is dictated by order of the repositories as configured in the pgbackrest.conf (e.g. repo1 will be checked before repo2). To restore from from a specific repository, the --repo option can be used.
PITR can be performed by specifying --type=time and specifying the target time with --target. If a backup is not specified via the --set option, then the configured repositories will be checked for a backup that contains the requested time. If no backup can be found, the latest backup from the first repository containing backups will be used.
$ mkdir /tmp/restored_data $ pgbackrest restore --stanza=demo --target="RP1" --type=name --no-delta --pg1-path=/tmp/restored_data P00 INFO: repo1: restore backup set 20210419-143643F $ rm -rf /tmp/restored_data/* $ pgbackrest restore --stanza=demo --target="2021-04-19 14:38:55.313716+00:00" --type=time --no-delta --pg1-path=/tmp/restored_data HINT: time format must be YYYY-MM-DD HH:MM:SS with optional msec and optional timezone (+/- HH or HHMM or HH:MM) - if timezone is omitted, local time is assumed (for UTC use +00) P00 INFO: repo1: restore backup set 20210419-143643F $ rm -rf /tmp/restored_data/* $ pgbackrest restore --stanza=demo --target="RP1" --type=name --no-delta --pg1-path=/tmp/restored_data --repo=2 P00 INFO: repo2: restore backup set 20210419-143749F
Even if the backup in repo2 is newer, the first found match is preserved. Let's take a new backup in repo1 to check if pgBackRest will auto-select the backup in repo2:
$ pgbackrest backup --stanza=demo --type=full --repo=1 P00 INFO: backup command begin ... P00 INFO: execute non-exclusive pg_start_backup(): backup begins after the requested immediate checkpoint completes P00 INFO: backup start archive = 00000001000000000000001B, lsn = 0/1B000028 P00 INFO: full backup size = 63MB P00 INFO: execute non-exclusive pg_stop_backup() and wait for all WAL segments to archive P00 INFO: backup stop archive = 00000001000000000000001B, lsn = 0/1B000138 P00 INFO: check archive for segment(s) 00000001000000000000001B:00000001000000000000001B P00 INFO: new backup label = 20210419-144656F P00 INFO: backup command end: completed successfully P00 INFO: expire command begin ... P00 INFO: repo1: expire full backup 20210419-143643F P00 INFO: repo1: remove expired backup 20210419-143643F P00 INFO: expire command end: completed successfully $ pgbackrest info --stanza=demo stanza: demo status: ok cipher: none db (current) wal archive min/max (13): 000000010000000000000018/00000001000000000000001B full backup: 20210419-143749F timestamp start/stop: 2021-04-19 14:37:49 / 2021-04-19 14:38:03 wal start/stop: 000000010000000000000018 / 000000010000000000000018 database size: 63MB, database backup size: 63MB repo2: backup set size: 10MB, backup size: 10MB full backup: 20210419-144656F timestamp start/stop: 2021-04-19 14:46:56 / 2021-04-19 14:47:10 wal start/stop: 00000001000000000000001B / 00000001000000000000001B database size: 63MB, database backup size: 63MB repo1: backup set size: 10MB, backup size: 10MB $ rm -rf /tmp/restored_data/* $ pgbackrest restore --stanza=demo --target="2021-04-19 14:38:55.313716+00:00" --type=time --no-delta --pg1-path=/tmp/restored_data P00 INFO: repo2: restore backup set 20210419-143749F
The recovery process may be complex and tricky depending on the target, and therefore, the info command can really be helpful to determine the repository to restore from.
Archive Get Command
When multiple repositories are configured, WAL will be fetched from the repositories in priority order (e.g. repo1, repo2, etc.). In general it is better if faster storage has higher priority. The command can operate on a single repository by specifying it with the --repo option.
root# systemctl stop edb-as-13.service $ mv /var/lib/edb/as13/data /var/lib/edb/as13/data.orig $ mkdir -m 700 /var/lib/edb/as13/data $ pgbackrest restore --stanza=demo --target="2021-04-19 14:38:55.313716+00:00" --type=time --no-delta --target-action=promote P00 INFO: restore command begin ... P00 INFO: write updated /var/lib/edb/as13/data/postgresql.auto.conf P00 INFO: restore global/pg_control (performed last to ensure aborted restores cannot be started) P00 INFO: restore command end: completed successfully $ cat /var/lib/edb/as13/data/postgresql.auto.conf|grep restore_command restore_command = 'pgbackrest --stanza=demo archive-get %f "%p"' root# systemctl start edb-as-13.service $ cat /var/lib/edb/as13/data/log/edb-2021-04-19_145147.log ... LOG: starting point-in-time recovery to 2021-04-19 14:38:55.313716+00 P00 INFO: found 000000010000000000000018 in the repo2: 13-1 archive P00 INFO: found 000000010000000000000019 in the repo2: 13-1 archive LOG: recovery stopping before commit of transaction 1183, time 2021-04-19 14:38:55.314118+00 LOG: redo done at 0/19000100 P00 INFO: unable to find 00000002.history in the archive LOG: selected new timeline ID: 2 LOG: archive recovery complete P00 INFO: pushed WAL file '00000002.history' to the archive $ ls /var/lib/edb/as13/backups/repo*/archive/demo/13-1/00000002.history /var/lib/edb/as13/backups/repo1/archive/demo/13-1/00000002.history /var/lib/edb/as13/backups/repo2/archive/demo/13-1/00000002.history
PostgreSQL found the WALs needed for recovery in our repo2, picked a new timeline and pushed the history file to the repositories.
Whenever a new timeline is created, PostgreSQL creates a timeline history file that shows which timeline it branched off from and when. These history files are necessary to allow the system to pick the right WAL segment files when recovering from a backup that contains multiple timelines.
root# systemctl stop edb-as-13.service $ rm -rf /var/lib/edb/as13/data/* $ rm -rf /var/lib/edb/as13/backups/repo1/archive/demo/13-1/00000002.history $ pgbackrest restore --stanza=demo --target="2021-04-19 14:38:55.313716+00:00" --type=time --target-timeline=current --no-delta --target-action=promote P00 INFO: restore command begin ... P00 INFO: repo2: restore backup set 20210419-143749F P00 INFO: write updated /var/lib/edb/as13/data/postgresql.auto.conf P00 INFO: restore global/pg_control (performed last to ensure aborted restores cannot be started) P00 INFO: restore command end: completed successfully root# systemctl start edb-as-13.service $ cat /var/lib/edb/as13/data/log/edb-2021-04-19_145721.log P00 INFO: found 00000002.history in the repo2: 13-1 archive P00 INFO: unable to find 00000003.history in the archive LOG: selected new timeline ID: 3 P00 INFO: pushed WAL file '00000003.history' to the archive
As shown above, since the history file is stored within the same repository as the restored backup set, PostgreSQL is able to pick a new and accurate timeline.
Let us now retry after moving the history file to repo1.
root# systemctl stop edb-as-13.service $ rm -rf /var/lib/edb/as13/data/* $ mv /var/lib/edb/as13/backups/repo2/archive/demo/13-1/00000002.history /var/lib/edb/as13/backups/repo1/archive/demo/13-1/00000002.history $ pgbackrest restore --stanza=demo --target="2021-04-19 14:38:55.313716+00:00" --type=time --target-timeline=current --no-delta --target-action=promote root# systemctl start edb-as-13.service $ cat /var/lib/edb/as13/data/log/edb-2021-04-19_150037.log P00 INFO: found 00000002.history in the repo1: 13-1 archive P00 INFO: found 00000003.history in the repo1: 13-1 archive P00 INFO: unable to find 00000004.history in the archive LOG: selected new timeline ID: 4 P00 INFO: pushed WAL file '00000004.history' to the archive
As we can see, both 00000002.history and 00000003.history have been found in repo1 so PostgreSQL could pick the next timeline correctly, even if the restored backup set came from repo2.
When using multiple repositories, the archive-get command will tolerate gaps in one repository (due to lack of disk space e.g.) mainly because it will still be able to find the missing files in the other repository.
- On this page
- Configuration
- Initialization
- Backups
- Restore
Could this page be better? Report a problem or suggest an addition!