Hello,
When i try to open a port bigger than 9999 is not working, i have a webserver i put on port 11211, i create an inbound rule in firewall for this port, i create a rule in security group to accept connection on this port but the port is still close. When i change port with a port from range 1024-9999 and i made same settings is working.
Verify that the subnet allows traffic on that port. If you use the Network Reachability Analyzer (it is now under AWS Network Manager), it can show you what is causing the block.
