We have software that automatically sets up terminal servers. We support a large line (Digi, Lantronix, Chiyu, etc). We are looking at integrating your NCD5500 Gen3 into our software.
The other TS we interface with offer a TELNET port to allow for setup via software (rather than the web admin which is difficult for automated software to utilize). However, I can’t find any such access on your device.
I do note, however, that you have a Windows Configuration Tool - so I suspect that some such ability exists.
Our software is all in C and running on Debian devices.
Does your device support non-web setup, and if so can I get access to how to do this?