Thanks for reply, but I have 120 databases running on a one single instance. So it's not possible to take backup of instance instead of taking pg_dumb of all databases separately.
Example: suppose we have two instances running on single server, instance A having 120 databases and instance B having 50 databases and I want to move all databases running on instance A to another server having same postgres version and server configuration.
So,please suggest how i can move instance A to another server.