topic Re: how to configure Firewall in Operating System - Linux

how to configure Firewall

Guna_2 — Thu, 11 Jan 2007 05:12:44 GMT

Dear all

I am having 2 ip address in my linux box. I want to configure my firewall in such a way that, If telnet request is coming from one setof ip address it should accept and if it is from another set of ip address it should deny.

Is it possible with linux basic firewall

If possible please tell me how to configure that.

Thanks And Regards,
Guna

Re: how to configure Firewall

g33k — Thu, 11 Jan 2007 06:29:46 GMT

if basic firewall for you is IPTABLES.

Then its easy.

iptables -A INPUT -d 192.168.0.5 --destination-port 23 -j ACCEPT

allows telnet on ip address 192.168.0.5 or you can use -i eth0 if the interface is eth0.

You should you use DROP for deny.

But it depends how you iptables is set now...

More info here
http://www.linuxguruz.com/iptables/howto/

Re: how to configure Firewall

Wouter Jagers — Thu, 11 Jan 2007 15:12:57 GMT

Hiya,

Also, you could check how to use the hosts.allow and hosts.deny files (man, google).

But most of all, for some level of security, I would recommend using ssh and disabling telnet alltogether ;-)

Cheers

Re: how to configure Firewall

Wouter Jagers — Thu, 11 Jan 2007 15:15:18 GMT

Sorry, I guess I misread your question. You probably want to accept connections to one of your IPs and not connections the other. Forget about hosts.allow and hosts.deny then (well, don't forget, but it won't help you here).

My advice on ssh is still valid, though.

Cheers