Mission impossible : How to open ports on rooted server

  • Hello Everyone !


    i'm trying to open ports on my netcup rooted server but to no avail.


    I'm running ubuntu server 22.04, configured UFW correctly (at least i think), still can't access any port from outside.


    Only 22 is open, nothing else.


    Even disabling UFW makes no difference. i thought disabling it would make every port accesible.

    afaik there is no firewall on rs ?


    Thank you so much for your lights.


    Have a great day


    Mat

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  • Red

    Changed the title of the thread from “Mission impossible : How to open port on rooted server” to “Mission impossible : How to open ports on rooted server”.
    • Best Answer

    i'm using UFW, do i need to go through nftables ?

    Yes, of course (in case you are using nftables and not iptables). Who knows, which other tools have manipulated the settings.


    every other port stays close no matter what i do in UFW.

    And which server is running on port 3000? Check it with "netstat -tulpen" or "ss -tulpen".



    //Add:

    There is no server running in Port 3000. That is the reason why the port is closed.

  • I have no clue what i'm looking at

    It shows you which Services on your system are running and on what Port they are listening. There are no services running on Port 3000

    Meine (Netcup) Produkte: S 1000 G7, VPS 200 G8 Ostern 2019, IPs, Failover..

    Thanks 1
  • It shows you which Services on your system are running and on what Port they are listening. There are no services running on Port 3000

    Ho my ho my, so if no service is running/listening on said port, they stay "closed" ?


    i tried to open the port before installing the services... that may explain a lot.


    i guess i have a lot more to learn about networking.


    Thank you Lukay, and thank you Frank !

  • Yes, of course (in case you are using nftables and not iptables). Who knows, which other tools have manipulated the settings.


    And which server is running on port 3000? Check it with "netstat -tulpen" or "ss -tulpen".

    //Add:

    There is no server running in Port 3000. That is the reason why the port is closed.

    I wiped the OS 3 times wondering what was happenning so no other tools manipulating stuff. only my ignorance of how things works ^^


    Thank you again ! will try to install the service first ;)

  • Red

    Selected a post as the best answer.
  • Ho my ho my, so if no service is running/listening on said port, they stay "closed" ?

    Yes. From the outside there is no difference between a closed Firewall and no service that could answer the requests. The Tool used to check the state of the Port can just see that no one respondes.

    Meine (Netcup) Produkte: S 1000 G7, VPS 200 G8 Ostern 2019, IPs, Failover..

    Like 1