Q:

Unable to establish connectivity on a port after configuring proper rules

I have a Linux VM on azure, which I can access using SSH without any issues. I needed access to another port(lets say 7077) from outside, and here is what i have done so far, but unable to establish connectivity

Created an inbound rule from the networking settings, it created the rule on the Network security Group attached to the network interface.
Added a new Network Security Group, attached it to the Subnet

If I do a netcat request on port 22, i get a successful connectivity, but for the port 7077 I get connection refused. 
Also with IP flow verification passes for the port
Any pointer would be helpful. 

A:

You need to allow that same port in the firewall settings of the VM. The OS itself is what is refusing the connection suggesting you have not setup any firewall rules to allow that port. 
Try adding a allow rule in the firewall settings and see if you can reach that port. 
https://www.digitalocean.com/community/tutorials/how-to-list-and-delete-iptables-firewall-rules
http://www.thegeekstuff.com/2011/02/iptables-add-rule/
Ubuntu 17.04
https://help.ubuntu.com/lts/serverguide/firewall.html

