Thank you for your post!
More than the Firewall on the Server you will need to setup Port Forwarding on the Network to allow outside connections. This is Port forwarding information that might help understand this process. Setting this up might require looking up Router Settings or calling your Internet Service Provider.
I set up the port forward for FMS 12 and 15.
The web direct is working on FMS15 now.
Is there any special setting for the port forward rule?
WebDirect would be using ports 80 and 443 while FileMaker Pro uses Port 5003. If the Port Forwarding isn't configured properly the FileMaker Pro 15 may not be hitting the FileMaker Server 15. Improperly configured Network could even cause it to be forwarded to the FileMaker Server 12, which FileMaker Pro 15 is not compatible with.
This doesn't look like port forwarding. the firewall simply opens or allows certain ports. The forwarding is done on the router. Katherine router interface.
Via the router interface . . .
If you are running 2 servers then you will need two external IP addresses, or a port remapping to connect to each server.
This is because you can only forward one external port to one internal server. It is not possible to forward one port to two servers otherwise your router would not know which server to send you to each time you attempt to connect!
If you have 2 separate external IP addresses from your ISP you could port forward external IP addresses
22.214.171.124:5003 to your FMS12 server
126.96.36.199:5003 to your FMS15 server
(Note those are example IP addresses) Then externally from FileMaker each IP address will connect to a different server. So use the .2 address to connect to the new server, and the .1 address to connect to the old server.
Alternatively you could remap another external port to internal port 5003 on the FMS15 server
map external port 5003 -> to internal address 10.0.0.9:5003 your FMS12 server
map external port 55000 -> to internal address 10.0.0.6:5003 your FMS15 server
Externally then you would point FileMaker to server 188.8.131.52:55000 to get to the FMS15 server. (Again using example IP addresses).
Sorry that this is such a complicated post, but networks are complicated...
Thanks for help to Carls and Rick.
I thoght I set up the port 5003 for 10.0.0.6 but I did not.
Now, the problem is solved.