Yes the single EBS volume will work. As long as a filesystem only spans a single EBS volume and in your case they all share the same single EBS volume. If each had there own volume; that too would work using multiple snapshots as one coherent backup. i.e. pg_start_backup() take snapshot: /pgsql/pdbabe/data take snapshot: /pgsql/pdbabe/tsdata take snapshot: /pgsql/pdbabe/tsindex take snapshot: /pgsql/pdbabe/tstemp take snapshot: /pgsql/pdbabe/xlog Pg_stop_backup() And of course the associated WALs and future WALs.
