Trying to install Cloudcmd with portainer but getting errors

I used Technodadlife's videos to install Cloudcmd and Watchtower on my OMV4 NAS while using the old plugin for Plex. That Plex plugin was rather outdated and some issues where popping up so I recently installed OMV5 and managed to get Plex running using Portainer without too much fuss. Today I tried to install Cloudcmd and using this https://forum.openmediavault.o…mpose-files-in-Portainer/ and the compose info from cloudcmd's docker page. When I deployed it, I got this error

Deployment error
Error response from daemon:
driver failed programming
external connectivity on
endpoint cloudcmd_web1
(800fc4dd09f252433badb8f84a5f
e2dd58add6862b2d1c48efcf9968
dc903403):  Bind for 0.0.0.0:8000
failed: port is already allocated

So at this point I have no idea what is wrong so I removed the container and tried again, same error.

Could someone help me understand what I did wrong and how I might fix it and get Cloudcmd up and running?

Thanks

Is there a way to check which ports are in use or can I just use 8002 for instance ?

Please excuse me for all the questions, I am quite the novice using the command line. I used putty to log in as root and tried to run the telnet command like you listed but using my ip address and got "Command not found". Still, I tried to use port 8002 for the compose argument and got it to deploy and run, but when I went to my ip:8002, it would not connect in my browser, any ideas why?

version: '2'
services:
  web:
    ports:
      - 8000:8000
    volumes:
      - ~:/root
      - /:/mnt/fs
    image: coderaiser/cloudcmd

That is the compose contents I used but changed the port to 8002. While poking around the image details in Portainer, I noticed that within the dockerfile details section, it shows "expose" 8000/tcp and one of the last image layers is called expose 8000. Could this be the problem, even though i change the port, it is still exposing 8000 so things don't work?

I don't have a compose file, I used the stack function and pasted the compose info into it as shown in the link in my first post which generates the container within portainer. This is the actual information i used

version: '2'
services:
  web:
    ports:
      - 8002:8002
    volumes:
      - ~:/root
      - /:/mnt/fs
    image: coderaiser/cloudcmd

That worked, thank you very much for your help and patience gderf.

Yes, I figured that out, thanks again