Re: how do I set the MAC address in POSTROUTING?

[Pascal Hambourg <pascal.mail@plouf.fr.eu.org>]

Hello,

sean a écrit :
> Daniel Musketa wrote:
>>
>> AFAIK MAC addresses are used in ethernet to address ethernet frames. 
>> On ip routed ppp0 no ethernet frames arrive.
> 
> OK. If that's the case, then the --mac-source target would only work on 
> a LAN, not over the ethernet.

I guess you mean over the *in*ternet. Ethernet is a LAN technology.

> This would mean thatthe --mac-sourse 
> target has very limited use - only on local LANs.

Indeed, the scope of a MAC address is link local, limited to the LAN.

> But there is still a place for a MAC address.

On an IP/PPP link ? No way. A PPP interface has no MAC address, it is 
useless. There is a place only in the lines that the LOG target prints 
because they have a fixed format.

> How can I  put one in the 
> packet on the client side? This would allow me to use it over the internet.

You cannot use MAC addresses over an IP/PPP link. You cannot rely on MAC 
addresses over the internet either because this is layer 2 information 
that is not routed by definition.