2016-10-18 22:11:30 UTC [13107-1] FATAL: database files are incompatible with server
2016-10-18 22:11:30 UTC [13107-2] DETAIL: The data directory was initialized by PostgreSQL version 9.6, which is not compatible with this version 9.4.9.
It seems the old-datadir /var/lib/postgresql/9.4/main is init by postgres version 9.6?