Magnus Holmgren wrote:
> On Thursday 21 September 2006 22:52, Fernando Barajas took the opportunity to
> say:
>
>>Hi! I run a webhosting business here in Mexico, and I have my server
>>hosted at EV1 servers. My server runs Linux RHEL with Cpanel and Exim
>>as the MTA.
>>
>>Do you know if ther's a way that I could send different domains' mails
>>from a different IP? That is, that all mails from *@domain1.com will
>>go out from IP "11.22.33.44", and all mails from "*anotherdomain.com"
>>will go out from IP "55.66.77.88"?
>>
>>I have 2 IPs on my server, and they respond to different domains for
>>HTTP, but all the mail that comes out from my server comes from the
>>server's main IP.
>
>
> This should really be in the FAQ...
>
> See for example
> http://www.exim.org/mail-archives/exim-users/Week-of-Mon-20060612/msg00046.html
>
>
Which includes;
"The problem is that it's not always possible to choose a domain unambigously.
For example, if several messages are queued for one remote host they will be
sent over the same connection even if they are associated with more than one
of your local domains."
- AFAIK, that *can* be overcome by use of appropriate routers as well as
transports. Ours seem to work anyway...
"For that reason it's probably better to use a "neutral" interface and hostname
to send from."
Having tried it the other way, I'd have to say that this part is good advice
wherever possible, *especially* when one is contemplating using 'helo_data' for
more (virtual) domains than one has separate IP's for.
The 'receiving' MTA will (ordinarily) do a lookup on the IP it receives the
connection from, not 'trust' what you have sent as a HELO.
This means either an outright mismatch OR a dice-roll (where more than one PTR
record references the same IP).
Bill
