It would be nice to have an option in the Connect dialog to enter the combination of an IP address and a custom TCP port number (other than the default 35021).
A situation in which this can be very useful is, when there are multiple drives connected to a single EoE network, and the engineering PC cannot be directly connected to a local network, for example when using routed access or when accessing (remotely) via a VPN tunnel.
For example, for remote access, we can add a port forwarding to our Codesys master (a Linux-based system with the Codesys SL runtime) to a single drive:
iptables -t nat -A PREROUTING -p tcp --dport 35021 -j DNAT --to-destination 172.16.0.3
but this cannot be done for multiple drives, because port 35021 can only be forwarded once.
We could make multiple port forwardings in the master, for example:
port 10002 -> 172.16.0.2:35021
port 10003 -> 172.16.0.3:35021
port 10004 -> 172.16.0.4:35021
port 10005 -> 172.16.0.5:35021
port 10006 -> 172.16.0.6:35021
etc
This way, all individual drives can still listen to port 35021 (so no firmware change is needed), but the various drives can be accessed from the Engineering software by connecting to the IP-address of the Codesys master on port 10002-10006.
The only problem is currently, that the Engineering software cannot be told to connect to a custom port number.
(double axis units may also pose a complication, because they occupy 2 IP addresses).
(aside: the SafeX Engineering software has a dropdown with several port numbers in its connection settings dialog, but CtrlX Drive Engineering doesn't).
The current work-around is to remove the port forwarding and change it to a different destination, every time we need to switch between drives, but that is quite tedious and hard to explain to colleagues without Linux expertise.
