Transparent firewall

Transparent firewall

[Janos Makadi]

Hi,

I have a problem, and I don`t know how to solve it.

What I would like to do is this:

I have a database server and I want to protect it. It has one nic 
connected to the local network. I want to setup a new linux box with two 
nics connected to the same ip network like this:

        ****        ****
  ------*  *--------*  *
        ****        ****

       Linux       RDBMS

Every traffic has to go through the Linux box, and filter out the 
unneded packets. I dont know how to config the linux to use the same ip 
network with this confoguration. Let me explain. For example the server 
has 10.1.0.5/255.255.255.0 address, and all the clients use this network 
config too. What ip addresses is allowed to use with the linux box? I 
mean can I use 10.1.0.4, 10.1.0.3 for the two nics at the linux box?

Any RTFM answers, with links is appreciated.

Thanks,

Janos Makadi

RE: Transparent firewall

[Aldo Lagana]

you want to BRIDGE the two interfaces - look at ebtables and BRIDGING HOW-TO

-----Original Message-----
From: Janos Makadi [mailto:maki@freemail.hu]
Sent: Wednesday, June 02, 2004 4:10 PM
To: netfilter@lists.netfilter.org
Subject: Transparent firewall


Hi,

I have a problem, and I don`t know how to solve it.

What I would like to do is this:

I have a database server and I want to protect it. It has one nic 
connected to the local network. I want to setup a new linux box with two 
nics connected to the same ip network like this:

        ****        ****
  ------*  *--------*  *
        ****        ****

       Linux       RDBMS

Every traffic has to go through the Linux box, and filter out the 
unneded packets. I dont know how to config the linux to use the same ip 
network with this confoguration. Let me explain. For example the server 
has 10.1.0.5/255.255.255.0 address, and all the clients use this network 
config too. What ip addresses is allowed to use with the linux box? I 
mean can I use 10.1.0.4, 10.1.0.3 for the two nics at the linux box?

Any RTFM answers, with links is appreciated.

Thanks,

Janos Makadi


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RE: Transparent firewall

[Jeremy Jones]

You want bridging.  Start here: http://bridge.sourceforge.net/

jeremy jones

-----Original Message-----
From: netfilter-admin@lists.netfilter.org
[mailto:netfilter-admin@lists.netfilter.org] On Behalf Of Janos Makadi
Sent: Wednesday, June 02, 2004 2:10 PM
To: netfilter@lists.netfilter.org
Subject: Transparent firewall


Hi,

I have a problem, and I don`t know how to solve it.

What I would like to do is this:

I have a database server and I want to protect it. It has one nic 
connected to the local network. I want to setup a new linux box with two

nics connected to the same ip network like this:

        ****        ****
  ------*  *--------*  *
        ****        ****

       Linux       RDBMS

Every traffic has to go through the Linux box, and filter out the 
unneded packets. I dont know how to config the linux to use the same ip 
network with this confoguration. Let me explain. For example the server 
has 10.1.0.5/255.255.255.0 address, and all the clients use this network

config too. What ip addresses is allowed to use with the linux box? I 
mean can I use 10.1.0.4, 10.1.0.3 for the two nics at the linux box?

Any RTFM answers, with links is appreciated.

Thanks,

Janos Makadi

Re: Transparent firewall

[Janos Makadi]

Jeremy Jones wrote:

> You want bridging.  Start here: http://bridge.sourceforge.net/

Thanks for the answers. I start reading and learning.


Regads,

Janos Makadi

Re: Transparent firewall

[T. Horsnell (tsh)]

We have a similar scheme between our LAN and the University-owned
router, and we use proxy-arp instead of bridging (bridging wasnt
available when we first started 3 years ago)

Cheers,
Terry.


>Jeremy Jones wrote:
>
>> You want bridging.  Start here: http://bridge.sourceforge.net/
>
>Thanks for the answers. I start reading and learning.
>
>
>Regads,
>
>Janos Makadi
>
>
>
>