SSH tunneling to your secured database/RDS through bastion/jump server with forwarded port

by 
$ ssh -f -N -v -t -L 5433:target_host:5432 user@jump_server
  • target_host is the host/database_server/RDS that you want to access that only can be accessed from jump _server or bastion if you’re using AWS
  • jump_server is the host that accessible from you and the only host that can access target_host
  • 5432 is local port (postgresql default)
  • 5433 is the forwarded host/database_server/RDS port that you can access through localhost
    What’s next?
    Afterwards, you should be able to get postgresql open with forwarded port through localhost (5433).

    Test the forwarded port using telnet:

    $ telnet localhost 5433

    or using netcat:

    $ nc -vz localhost 5433