Setup internet-> firewall->masquerading router->private network

Setup internet-> firewall->masquerading router->private network

Post by Art Gonzal » Sun, 04 Nov 2001 07:31:12



Hello:

I'm involved in a project to implement the following scheme using
Redhat Linux 7.1.

SETUP:

   INTERNET
      |
 eth0 206.254.0.13        GATEWAY=school router
   FIREWALL
 -----------------------------------------------\
|eth1 206.254.0.33        GATEWAY=206.254.0.13
|      |                                           SUBNET
|eth0 206.254.0.34        GATEWAY=206.254.0.33(?)
 ------------------------------------------------/
   MASQ ROUTER
 eth1 10.10.15.3          GATEWAY=206.254.0.33
      |
 PRIVATE 10 block NETWORK

However we are having problems setting up the firewall.  Currently, if
we remove the firewall we can ping externally; however, upon setting
up the firewall we can't ping from the MASQ router to an external
address.  Yet from the firewall we can ping externally.  Please any
hints or suggestions.
If more information is needed let me know.

Art

 
 
 

Setup internet-> firewall->masquerading router->private network

Post by Dean Thompso » Sun, 04 Nov 2001 17:56:22


Hi!,

Quote:> I'm involved in a project to implement the following scheme using
> Redhat Linux 7.1.

> SETUP:

>    INTERNET
>       |
>  eth0 206.254.0.13        GATEWAY=school router
>    FIREWALL
>  -----------------------------------------------\
> |eth1 206.254.0.33        GATEWAY=206.254.0.13
> |      |                                           SUBNET
> |eth0 206.254.0.34        GATEWAY=206.254.0.33(?)
>  ------------------------------------------------/
>    MASQ ROUTER
>  eth1 10.10.15.3          GATEWAY=206.254.0.33
>       |
>  PRIVATE 10 block NETWORK

> However we are having problems setting up the firewall.  Currently, if
> we remove the firewall we can ping externally; however, upon setting
> up the firewall we can't ping from the MASQ router to an external
> address.  Yet from the firewall we can ping externally.  Please any
> hints or suggestions.
> If more information is needed let me know.

I would check your gateway/routing table on the firewall.  I am not sure why
eth0 on the firewall has got a proper IP address, unless you are feeding a set
of machines on a DMZ.  If that is the case, then the DMZ machines should use
the IP address: 206.254.0.34 as their gateway, and the firewall machine should
be using the IP address of: 206.254.0.13 as its gateway.

Check to make sure that you remove a duplicate route entry which is most
likely on the firewall.

See ya

Dean Thompson

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