Re: Problem reexplained.....

["Jörg Harmuth" <harmuth@mnemon.de>]

Jörg Harmuth wrote:
> Alaios wrote:
>> Let me reexplain the problem plz
>>> From src 143.233.222.253 starts some traffic that goes
>> to the 143.233.222.77 this is the eth1 of the laptop
>> The laptop has also one more interface the 10.2.4.1
>> that is connected back to back (cross cable) with the
>> interface of an other pc with ip address 10.2.4.2
>> IO want the traffic that reaches 143.233.222.77 reach
>> the 10.2.4.2
>> This is the first step.. when i succesfully implement
>> this then the next step is to forward this traffic
>> from the pc to a second pc... ( i ll use the same
>> methodology if step one works)
>> So now we can only focus to the first step
>> Plz take in mind that i dont have any firewall enables
>> /proc/sys/net/ipv4/ip_forward is set to 1. I have no
>> other iptables rules applied... I will only apply what
>> u ll write to do..
>> Before applying any iptables rules firstly i do
>> iptables -F iptables -F -t nat
> 
> 
> First do as AragonX recommended. There is no sense in continuing if the 
> basics aren't ok. Additionally check if the default gateway of 10.2.4.2 
> is set to 10.2.4.1. Then try Edmundo's approach and add
> 
> iptables -t nat -A POSTROUTING -o eth1 -j SNAT \
>          --to 143.233.222.77
> 
> Question: Is 143.233.222.77 a dial-up interface ?
> 
> If it doesn't work tcpdump on 143.233.222.77, then on 10.2.4.1,..., 
> briefly: find the point, where it breaks. You may post the dumps. Some 
> surrounding information could help too: ifconfig, route -n, 
> iptables-save, hmm - I think that should do.
> 
> Good luck,
> 
> Joerg


Humm, I should have read the whole thread before posting, especially the 
previous one :( My fault.

Yes, indeed. In the first place this is a routing problem. Read Nicks 
charming explanation of subnet masks and you will see, that it can't 
work. Do as others recommended: put a box between or change 253 to 
something lower than 127 or change your network from 64/26 to 192/26 or 
add a default gateway (you could try route add default eth1 - maybe it 
works) - whatever you are able to do. But first fix your routing.

Good luck,

Joerg