This article is about how to make backup of a database from filesystem in PostgreSQL. Also provides details on how to make and restore the database from filesystem. If you have come across case where you are required to start 'psql' database from filesystem backup. There might be case that some of Ubuntu files crashed during a blackout. The Ubuntu needs to be reinstalled. You do not have database backup files, you have somehow restored filesystem, or situation like, you forgot the AWS root password and you need to redo all setup right from database on other instance. This post is about second case, where I forgot the AWS root password, so I have attached the filesystem to other instance