TRS Default Port 83? or 81?

[Coopbase]

Hello, I am kind of confused as to what is the default port number of Telerik Report Server (TRS) after installation, is it port 83? or port 81? I installed several pc of our client, some were 83 and 81. It says here in the docs https://docs.telerik.com/report-server/implementer-guide/setup/installation#:~:text=The%20Report%20Server%20web%20application,on%20port%2083%20by%20default. that it is port 83 but why is it that some of the servers got port 81? Is there a need of configuration here? Mind you that only 1 TRS running in one pc. 

If it changes to port 81, any particular reason as why it changes to port 81 instead of port 83?

[Lance | Manager Technical Support]

Hi Coopbase,

Yes, the default port we try to use is 83. However, if that is unavailable, we will then go to the next available port that isn't bound. For clarity, let me directly quote our IIS documentation:

"The Report Server installer performs a basic setup of the new Report Server web app by adding an HTTP binding under port 83, if available, or under the first subsequent available port."

If you'd like to read more, go here => IIS Configuration - Telerik Report Server.

Regards,
Lance | Manager Technical Support
Progress Telerik