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.
* 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.
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.
* Make the code more modular and object-oriented.
* Multiple Docker containers can now be created for a single test to simulate more realistic environments.
