Re: route outgoing smtp via a specific interface

[Antony Stone <Antony@Soft-Solutions.co.uk>]

On Monday 03 May 2004 12:25 am, Christer Ekholm wrote:

> Antony Stone <Antony@Soft-Solutions.co.uk> writes:
> > On Sunday 02 May 2004 11:50 pm, Christer Ekholm wrote:
> >> I have two IP-providers. And the faster one of them blocks smtp. I
> >> have been trying to route smtp to the slower while still routing
> >> everything else to the faster, without success. Is it possible at all?
> >
> > IProute2, http://lartc.org
>
> Thankyou for the answer. I have read that, and tried everything I
> could think of.

Ah.   Sorry if my previous response seemed a little terse - I did not realise 
you were aware of iproute2 and had tried so much of it already.

> I think my problem is that I need this to work from the host with the
> connections to the providers. (localhost).
>
> My next thought was to use iptables to add a SNAT rule. But SNAT is only
> allowed in POSTROUTING, and I think I would need that in OUTPUT

I would recommend that you do try such a rule, since POSTROUTING happens after 
OUTPUT (and FORWARD).

Try:

iptables -A POSTROUTING -t nat -p tcp --dport 25 -j SNAT --to 217.215.183.181

Regards,

Antony.

-- 
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