Im trying to upgrade PostgreSQL from 9.2.15 to 9.4.20 with this : /usr/pgsql-9.4/bin/pg_upgrade --old-bindir=/usr/bin --new-bindir=/usr/pgsql-9.4/bin --old-datadir=/var/lib/pgsql/ data --new-datadir=/var/lib/pgsql/9.4/data Can anybody help me with this? I also try -p port parameter not helped. Both databse instances are shut down. that give me this output : Performing Consistency Checks ----------------------------- Checking cluster versions ok *failure* Consult the last few lines of "pg_upgrade_server.log" for the probable cause of the failure. connection to database failed: could not connect to server: No such file or directory Is the server running locally and accepting connections on Unix domain socket "/run/postgresql/.s.PGSQL.50432"? could not connect to old postmaster started with the command: "/usr/bin/pg_ctl" -w -l "pg_upgrade_server.log" -D "/var/lib/pgsql/data" -o "-p 50432 -b -c listen_addresses='' -c unix_so cket_permissions=0700 -c unix_socket_directory='/run/postgresql'" start Failure, exiting -- Sent from: http://www.postgresql-archive.org/PostgreSQL-general-f1843780.html