Re: IP Alias with iptables

[Antony Stone <Antony@Soft-Solutions.co.uk>]

On Wednesday 21 April 2004 12:39 am, Rodrigo Haces wrote:

> Thanks for this, hope this is my last post:
>
> assuming this will allow all 192.168.1.0/24 go to 192.168.0.0/24 how could
> i do if i want not all the subnet, but only 192.168.1.10, i suppose is with
> the -s option, but im not sure of how to use this.

iptables -A FORWARD -i eth0 -o eth1 -s 192.168.1.10 -j ACCEPT

Regards,

Antony

> > -----Mensaje original-----
> > De: netfilter-admin@lists.netfilter.org
> > [mailto:netfilter-admin@lists.netfilter.org]En nombre de Antony Stone
> > Enviado el: Martes, 20 de Abril de 2004 01:33 a.m.
> > Para: Netfilter
> > Asunto: Re: IP Alias with iptables
> >
> > On Tuesday 20 April 2004 4:08 am, Rodrigo Haces wrote:
> > > New Situation:
> > >
> > > eth0: 192.168.1.1 Connected to hub 1
> > > eth1: 192.168.0.1 Connected to hub 2
> > >
> > > hub 1 is for guests
> > > hub 2 is for administrative porposes, and MUST be able to use network
> > > 192.168.0.x and 192.168.1.x
> >
> > So, the firewall needs to allow 192.168.1.0/24 addresses to connect to
> > 192.168.0.0/24 but not the other way round.
> >
> > > so this is something i thought.
> > >
> > > eth0... 192.168.1.1 netmask 255.255.255.0
> > > eth1... 192.168.0.1 netmask 255.255.0.0
> >
> > Doesn't look good.
> >
> > > eth1:1. 192.168.1.101 netmask 255.255.0.0
> >
> > Looks as bad as the first idea, with only one interface.
> >
> > > my laptop is part of the administrative sector, i have
> >
> > 192.168.0.10 ip, but
> >
> > > i need to be able to use also 192.168.1.10 so i can monitor guests,
> >
> > What is wrong with yur laptop havign just one IP address (that *is*
> > conventional, after all), and the firewall allowing it to
> > "monitor" addresses
> > in the other subnet?   Perhaps you should explain more about what
> > you mean by
> > "monitor"?
> >
> > > Any ideas
> >
> > Yes.   Have two subnets with separate address ranges, a firewall
> > in between,
> > and allow one subnet to connect to the other, but not the other way
> > round.
> >
> > eg:
> > eth0 192.168.1.1 netmask 255.255.255.0
> > eth1 192.168.0.1 netmask 255.255.255.0
> >
> > iptables -P FORWARD DROP
> > iptables -A FORWARD -m state --state ESTABLISHED,RELATED -j ACCEPT
> > iptables -A FORWARD -i eth0 -o eth1 -j ACCEPT
> >
> > Regards,
> >
> > Antony.
> >
> > --
> > Success is a lousy teacher.  It seduces smart people into
> > thinking they can't
> > lose.
> >
> >  - William H Gates III
> >
> >                                                      Please reply
> > to the list;
> >                                                            please
> > don't CC me.

-- 
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