XO Mail engineers?

Thu Aug 5 08:59:26 UTC 2004

Drew,

Here's the straight scoop:

The "New XO SMTP servers" are new in the sense that they go back to a 
1997 platform rather than a 1993 platform that smtp.concentric.net 
derives from.  They're both from the Concentric* part of XO, and both 
come out of my team, for what it's worth.

What we've been doing is consolidating some of the extremely old 
systems onto the newer platforms, where we've been focusing our 
development cycles for some time.  'smtp.concentric.net' isn't ceasing 
to exist, but it's now (or rather, extremely soon) will be on the 
up-to-date systems.

That said, we're not forcing people to host mail with us in order to 
use us for outbound relay.  The one restriction that will be imposed by 
the new smtp.concentric.net that the old one didn't do was to require 
the sender domain to exist on-platform rather than to allow completely 
unchecked relay by domain.  Domain hosting is bundled with all our DSL 
and other network access products, so for the vast majority of people, 
this is no problem, because we don't need to be authoritative, or have 
MX pointed to us, for this to work.  The one situation where people are 
impaired is if they want to send mail via a domain name of some other 
ISP (e.g. aol.com), in which case they should use the relays provided 
by their other ISP (we don't block outbound port 25 across the board), 
or if a customer is running a mail server/mailing list/etc of their 
own, where said server might send out mail from any domain, in which 
case that server should be doing its own MX routing and not relying on 
a relay.

Most of our DSL and other access customers that use an XO-provided 
relay are already on the newer platform and have been for a long time, 
and only a few remain with configurations still pointing at the older 
legacy systems.  So the actual impact here is quite small.

You may now all commence flaming this, and me :)

--David Schairer
VP/Chief Systems Architect
XO Communications, Inc.

* We have recently relaunched the Concentric brand for our email and 
hosting products -- www.concentric.com -- for those of you who remember 
it from the 'before time' :)  I have a few discount codes left for 
email/hosting accounts -- send me an email if interested.

On Aug 4, 2004, at 9:41 AM, Drew Weaver wrote:

>             It has come to my attention that XO has "done away" with 
> some of concentric's email systems and have replaced them with new "XO 
> SMTP servers" these new XO SMTP servers aren't allowing people who 
> don't have their mail hosted at XO to relay mail through them even 
> though they are XO DSL customers, you guys may want to rethink your 
> policy on this. It is generally the responsibility of the ISP to 
> provide the outgoing mail transport for your connected users.
>
>  
>
> -Drew
>
>  
>
>  