A connection to the primary cluster is still required to start/stop the backup and copy files that are not replicated, but the vast majority of files are copied from the standby in order to reduce load on the master.
Master and standby can both be configured on the backup server and pgBackRest will automatically determine which is the master. This means no configuration changes for backup are required after failing over from a master to standby when a separate backup server is used.
These include (depending on the version where they were introduced): pgsql_tmp, pg_dynshmem, pg_notify, pg_replslot, pg_serial, pg_snapshots, pg_stat_tmp, pg_subtrans. The postgresql.auto.conf.tmp file is now excluded in addition to files that were already excluded: backup_label.old, postmaster.opts, postmaster.pid, recovery.conf, recovery.done.
Bug Fixes:
* Fixed an issue where tablespace paths that had $PGDATA as a substring would be identified as a subdirectories of $PGDATA even when they were not. Also hardened relative path checking a bit. (Reported by Chris Fort.)
* Tablespace paths that had $PGDATA as a substring would be identified as a subdirectories of $PGDATA even when they were not.
* Also hardened relative path checking a bit.
Bug Fixes:
* Fixed an issue an where an extraneous remote was created causing threaded backup/restore to possibly timeout and/or throw a lock conflict. (Reported by Michael Vitale.)
* Fixed an issue where db-path was not required for the check command so an assert was raised when it was missing rather than a polite error message. (Reported by Michael Vitale.)
* Fixed check command to throw an error when database version/id does not match that of the archive. (Fixed by Cynthia Shang.)
* Fixed an issue where a remote could try to start its own remote when the backup-host option was not present in pgbackrest.conf on the database server. (Reported by Lardière Sébastien.)
* Fixed an issue where the contents of pg_xlog were being backed up if the directory was symlinked. This didn't cause any issues during restore but was a waste of space.
* Fixed an invalid log() call in lock routines.
Features:
* Experimental support for non-exclusive backups in PostgreSQL 9.6 beta3. Changes to the control/catalog/WAL versions in subsequent betas may break compatibility but pgBackRest will be updated with each release to keep pace.
Refactoring:
* Enhancements to the protocol layer for improved reliability and error handling.
* All remote types now take locks. The exceptions date to when the test harness and pgBackRest were running in the same VM and no longer apply.
* Exceptions are now passed back from threads as messages when possible rather than raised directly.
* Temp files created during backup are now placed in the same directory as the target file.
* Output lock file name when a lock cannot be acquired to aid in debugging.
* Reduce calls to protocolGet() in backup/restore.
* Suppress banners on SSH protocol connections.
* Improved remote error messages to identify the host where the error was raised.
This is a better approach than 93320b8 (reverted in this commit) because it ensures that the remote type will be none so any functions that utilize optionRemoteTypeTest will work correctly.
This bug was only an issue when backup-host was not properly configured on the database host.
Bug Fixes:
* Fixed an issue where keep-alives could be starved out by lots of small files during multi-threaded backup. They were also completely absent from single/multi-threaded backup resume and restore checksumming. (Reported by Janice Parkinson, Chris Barber.)
* Fixed an issue where the expire command would refuse to run when explicitly called from the command line if the db-host option was set. This was not an issue when expire was run automatically after a backup (Reported by Chris Barber.)
* Fixed an issue where validation was being running on archive_command even when the archive-check option was disabled.
Features:
* Added check command to validate that pgBackRest is configured correctly for archiving and backups. (Contributed by Cynthia Shang.)
* Added the protocol-timeout option. Previously protocol-timeout was set as db-timeout + 30 seconds.
* Failure to shutdown remotes at the end of the backup no longer throws an exception. Instead a warning is generated that recommends a higher protocol-timeout.
* Experimental support for non-exclusive backups in PostgreSQL 9.6 beta2. Changes to the control/catalog/WAL versions in subsequent betas may break compatibility but pgBackRest will be updated with each release to keep pace.
Refactoring:
* The pg_xlogfile_name() function is no longer used to construct WAL filenames from LSNs. While this function is convenient it is not available on a standby. Instead, the archive is searched for the LSN in order to find the timeline. If due to some misadventure the LSN appears on multiple timelines then an error will be thrown, whereas before this condition would have passed unnoticed.
* Option handling is now far more strict. Previously it was possible for a command to use an option that was not explicitly assigned to it. This was especially true for the backup-host and db-host options which are used to determine locality.
* Improved handling of users/groups captured during backup that do not exist on the restore host. Also explicitly handle the case where user/group is not mapped to a name.
* Changed version variable to a constant. It had originally been designed to play nice with a specific packaging tool but that tool was never used.
