How to open TCP port in Ubuntu 10.10?

Question

How to open TCP port in Ubuntu 10.10 ?

Solution 1

sudo iptables -A INPUT -p tcp --dport (port number) -j ACCEPT

Solution 2

Shooting in the darkness:

sudo ufw allow 80

Now there is a rule in your ubuntu firewall allowing external access to your 80 port. If you want more specific rule see man ufw. If you are on non-routable IP address you have to forward port in your router. If you provide more context to your question, then I can adjust this answer.

Solution 3

Your question needs a lot more detail:

• What do you mean by "open a port"? Do you want to do it in a program? Just run a program?
• What is your network configuration? LAN structure, Internet uplink, OSes involved, which router/switch...
• Do you have any firewalls / NAT in place? On your system, elsewhere in the network?

That said, if you have the "typical" home setup (one or more computers hooked up to a combined switch/router with Internet uplink via DSL or cable): Typically the switch/router/modem combo has a built-in firewall. You'll probably need to open a port there. Usually these devices have a web interface for configuration, look into your manuals.

Solution 4

I suggest Netcat: The very basic way to do that (via Netcat) is:

nc -l <port_number>

Example:

nc -l 12569

View more solutions

Comments

[Denys Cherepanin]

Belongs either on superuser.com or askubuntu.com.

[S.Hoekstra]

For what do you want to open the port? To host a service? to use for outgoing traffic? What do you want to achieve?

[weberc2]

This doesn't work under Ubuntu 12.10... nmap localhost -p80 still displays CLOSED

[SSH This]

@Romka no no, thats not how you ask a question, more info needed, this answer is correct

[Chris Moschini]

sudo ufw enable would be required first on a default Ubuntu install, since ufw is disabled by default.