The firwall ufw is inactive.
rstudio@ip-172-31-2-247:/opt/shiny-server/config$ sudo ufw status verbose
[sudo] password for rstudio:
I can tell you I have launched atleast a dozen shiny servers on AWS and faced "connection refused" error several times and it was most often resolved by config settings in the AWS EC2 security group (which is the virtual firewall). This time I am unable to find what that problem could be. I also tried exclusive 3838 port opening as well as all ports opening. Even after opening "All Traffic" on "All ports" from "All IP addresses" nothing seems to work.
I have another shinyapp working on another EC2 instance and it opens the default app successfully.
I cleared my browser cache and even changed the browser to Safari (from chrome) but no luck.
As the port 80 is open (I can access rstudio console) there seems to be some portr config that is missing somewhere. Would appreciate if you could suggest a step by step diagnosis for
error connection refused.
Note: This is a very common error encountered by many people (as I see stackoverflow) and is the starting problem almost everytime I start a new shiny server. Creation of an exhaustive checklist for this problem diagnosis will be really nice.