Problem fixed Re: HI, Problem get firewall going.

Neil Dugan ubuntu at butterflystitches.com.au
Mon Jul 31 15:27:47 BST 2006


Neil Dugan wrote:
> Michael Chesterton wrote:
> 
>> Neil Dugan <ubuntu at butterflystitches.com.au> writes:
>>
>>
>>> Hi I am new to this list, if this is the wrong place to ask let me know.
>>>
>>> I have setup a ubuntu box for internet access and also as a firewall.
>>> I can get on the internet from the firewall computer. :)   From the
>>> other computer I can ping both interfaces of the firewall (i.e. eth0
>>> and eth1).  :)
>>>
>>> But I can't ping the modem @ 192.168.1.1 :(
>>
>>
>>
>> First thought is the modem doesn't have a route for
>> 192.168.5/24. But I'm not sure if the firewall is masquerading.
> 
> 
> As far as I can tell it isn't doing anything as no packet info is logged
> 
> # route
> Kernel IP routing table
> Destination     Gateway         Genmask         Flags Metric Ref Use Iface
> 192.168.0.0     *               255.255.0.0     U     0      0 0 eth0
> default         192.168.5.254   0.0.0.0         UG    0      0 0 eth0
> 
>>
>>
>>> The eth1 interface of the firewall does report receiving bytes (via.
>>> ifconfig) but I can't trace where that info is going.  I put lots of
>>> LOG actions in the iptables to find out where the ping was going but
>>> none of them report anything.  The program ethereal says the eth1
>>> interface is receiving lots of ARP requests for 192.168.1.1 but no
>>> answers are sent.
>>
>>
>>
>> I don't think eth1 of the firewall should be be receiving arp requests
>> for 192.168.1.1, sounds like the computer thinks 192.168.1.1 is
>> directly connected to it's network, not via 192.168.5.254
>>
>>
>>
> Any way I can find out?
> I might have configured the DHCP wrong.
> 
> Regards Neil.
> 

I changed the config of the DHCP server, this changed the route table
on the computer attached to the firewall, this caused the ARP requests
to not be done, and everything worked.

Thanks Michael Chesterton for the hint.

Now all I have to do is the finish the firewall config.

Regards Neil.





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