Even though I’m not familiar with the intricacies of this tool’s installation, you should be able to access it using
<server-ip>:port as this rock-on is running in
If this doesn’t work, this may mean you have the port is question already used by something else.
I’ll take the opportunity of such a timely question to let you know that I am currently in the middle of reworking / implementing rock-on networking, and the possibility of adding / editing ports published by a given container was a possibility I thought about. While this is not something I am currently planning on implementing in my current work, this could very-well be the subject of future improvements. See the Github issue linked below where I mentioned this:
As you can see in the issue above and the related ones linked therein, I first need to lay out the ground work for rock-on networking and make sure it is implementing correctly. The next step will thus be to implement the kind of features like adding new ports and/or editing current ones.
Hope this helps, and let us know how it goes with the Webtools plugins.