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I am having a bit of trouble opening a port in Fedora Core, I run a command
nmap -P0 192.168.1.12
and returns a list of open ports... thats fine, i can see what ports are open. I tried using the command for iptables to open port 25 i did the iptables-save command and restarted iptables but it hasnt seem to have worked. I typed the command from a book which i dont have to hand at the moment... could anyone tell me a simple command to open a port number, and leave it opened, even after the pc or service has restarted (ie save that configuration for that port being opened)
while we are on the subject of opening ports.... anyone know how to do the reverse and close them?
Cheers for your help, its the one thing that i think is stopping my mail server from working (hopefully the only thing)
Distribution: debian, gentoo, os x (darwin), ubuntu
iptables-save is a command you should be using with iptables-restore. so you do
iptables-save > firewall.rules
at satrup you can have a script run
iptables-restore < firewall.rules
or something like that - have a look at the man pages.
by 'opening' port 25 on your firewall, does not mean that the port is really open! you need a service that is running on port 25, ie. postfix or exim
if you want to take care of the firewall rules yourself, rather than using the FC gui, i recomend you disable the FC firewall, and use the iptables command by hand, ie. writing a simple bash script, which you run at startup
google for iptables tutorial, one of the first 2 or 3 entries is a really good manual
the thing is, i have got postfix running, and my firewall is disabled. if i run the same nmap command on my routers ip address it says 25 closed and 53 is open (because i have my router mapped to the client pc for ports 25 and 53), so 53 seems to be open and im runing bind on that and 25 seems to be closesd yet i am running postfix on it. any further suggestions?