NAT IP POOL!

NAT IP POOL!

[Blizzards]

Hi list!


Those are my questions:

A)I need to SNAT a subnet 192.168.1.0/24 with 172.16.1.0/24.
I use this tule:
iptables -t nat -A POSTROUTING -s 192.168.1.0/24 -j SNAT --to 172.16.1.0/24
This is ok, but when i nat an address, i must create an ip alias on ethn 
an my nat box for this to work. Ok.
When i use few address no problem at all, but using a pool of address (a 
subnet or an interval of ip address), i must create 254 aliases for the 
interface or there was a better method?
B)Iptables Nat a pool of address with 1:1 method like cisco nat?
If yes, when no more address 1:1 are avaiable for connections, can i
se a PAT address like cisco nat?
Or iptables works differently balancing the load of ip address used?

Thanks in advance
Giulius.

Re: NAT IP POOL!

[Filip Sneppe]

On Thu, 2002-12-05 at 12:11, Blizzards wrote:
> Hi list!
> 
> 
> Those are my questions:
> 
> A)I need to SNAT a subnet 192.168.1.0/24 with 172.16.1.0/24.
> I use this tule:
> iptables -t nat -A POSTROUTING -s 192.168.1.0/24 -j SNAT --to 172.16.1.0/24
> This is ok, but when i nat an address, i must create an ip alias on ethn 
> an my nat box for this to work. Ok.
> When i use few address no problem at all, but using a pool of address (a 
> subnet or an interval of ip address), i must create 254 aliases for the 
> interface or there was a better method?
> B)Iptables Nat a pool of address with 1:1 method like cisco nat?
> If yes, when no more address 1:1 are avaiable for connections, can i
> se a PAT address like cisco nat?
> Or iptables works differently balancing the load of ip address used?
> 

Hi,

You probably want to look at the NETMAP target that is in patch-o-matic.
SNAT and DNAT targets will do some loadbalancing. You'll get weird
results with your setup.

With NETMAP you can do source NAT and destination NAT of whole subnets
with a strict 1:1 mapping.

Regards,
Filip

Re: NAT IP POOL!

[Blizzards]

>
>
>Hi,
>
>You probably want to look at the NETMAP target that is in patch-o-matic.
>SNAT and DNAT targets will do some loadbalancing. You'll get weird
>results with your setup.
>
>With NETMAP you can do source NAT and destination NAT of whole subnets
>with a strict 1:1 mapping.
>
Ok, but if i need to SNAT a whole subnet 192.168.1.0/24 with a short 
pool of address like 172.16.1.1-172.16.1.10
with a strict 1:1 only 10 ip are natted.
NETMAP give me the ability to write down a PAT address for the rest of 
connections?
Or for short pool it's better to setup interfaces aliases?

Thanks.
Giulius.

>
>Regards,
>Filip
>
>
>  
>