If checking remotely from the internet, there are several websites that will allow you to check if port 6001 (or any other port assigned) is open.
Port 6001 is the Clear-Com default port for Agent IC and IP panels. One of these websites is: https://www.yougetsignal.com/tools/open-ports/
When you access the site, you can edit the public IP associated with an IVC card or LQ (Remote Address), and the port. If the port is open or closed in the router/firewall, you'll get a message indicating this. see above & See attachment.
If checking internally, you could run a port scan program, or you could telnet into the local IVC or LQ IP address.
Make sure you can ping the IP
Open a command prompt
Type the command this way (using the local IP plus the port): "telnet 192.168.254.150:6001"
If you get a blank screen, there's a good chance the port is open. If you get an error message, the port is not.