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Hello I am running my server and since the ip is not static (my ISP won't give me one because I need to be a commercial customer) I have to use a service like DynDNS but the site is only accessible in my internal network I checked for open ports and 80 and 22 are opened but don't let traffic in and since I installed mysql and vsftpd I need to open the them I did ufw allow in 21/tcp it's says allow in anywhere but i scanned the ip on another computer with nmap and says most are closed. How can I open them?

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Did you already routed the ports via the NAT functions of your modem/router? Please let us know which modem/router brand name and model you own. BTW, for the web server you should route the 8080 port in order to send the petitions from outside to your server, otherwise, the modem web interface itself will respond to such petitions. I think everything may be ok in your server but your modem Network Address Translation may be incomplete. Give us the details on your modem/router and tell us if you already did the NAT in order to get the best support for your case. Welcome to AskUbuntu. :) –  Geppettvs D'Constanzo May 8 '13 at 21:47
You will need to set up port-forwarding in your router. Most routers require that you log into their Web interface to set this up. This works best when your server is using a fixed IP address on your internal network rather than a rotating address through DHCP. Like you, I use DynDNS and had to set up port-forwarding for each service. I would not open port 22 to the public, btw. Services like FTP, Apache/HTTP, MySQL will open their required ports when installed. You should be able to port scan your internal IP and see the open ports. –  douggro May 8 '13 at 22:00
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