When you run:

CompatTelRunner.exe /test:whatever

the program will… sleep for exactly 1 second.

The whatever bit can be any string, as long as it’s at least 1 character long.

In Windows 11 24H2+ and Windows Server 2025+ you can use new net.exe command line arguments to Configure alternative SMB ports: TCP, QUIC, RDMA:

• /TCPPORT <port>
• /QUICPORT <port>
• /RDMAPORT <port>

I am not the first one to point it out — see this article.