IP-tables configuration for a Workstation

Hi.

I've found the following IP-tables configuration for a Workstation:

(1) iptables –F
(2) iptables –X
(3) iptables –P INPUT DROP
(4) iptables –P OUTPUT ACCEPT
(5) iptables –P FORWARD DROP
(6) iptables –A INPUT –i lo –j ACCEPT
(7) iptables –A INPUT –m state --state ESTABLISHED,RELATED
–j ACCEPT

Could somebody tell me the meaning of the rule (6)? I guess that "lo" is
the "virtual" interface to the localhost (127.0.0.0), but: what's the
meaning of openning the loopback interface?

Thank you.

Jordi <(E-Mail Removed)> wrote:
> Hi.
>
> I've found the following IP-tables configuration for a Workstation:
>
> (1) iptables ?F
> (2) iptables ?X
> (3) iptables ?P INPUT DROP
> (4) iptables ?P OUTPUT ACCEPT
> (5) iptables ?P FORWARD DROP
> (6) iptables ?A INPUT ?i lo ?j ACCEPT
> (7) iptables ?A INPUT ?m state --state ESTABLISHED,RELATED ?j ACCEPT
>
> Could somebody tell me the meaning of the rule (6)? I guess that "lo" is
> the "virtual" interface to the localhost (127.0.0.0), but: what's the
> meaning of openning the loopback interface?

Try it with the rule, then without. You'll see.

--
William Park <(E-Mail Removed)>, Toronto, Canada
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