Not all IP addresses listed for SMTP server

[ChristianWickham]

I have a Windows 2008 R2 server with SMTP. The server has 4 network cards,
and three of these are Internet facing, and one is on the DMZ.
We are transitioning from a Windows 2003 SMTP server to Windows Server 2008
R2. On the Windows 2003 machine, I was able to pick the two IP addresses (one
external, one internal) for SMTP traffic, and obviously our firewall was
configured for these IP addresses and no others.

In the "IP Address" box on the SMTP Virtual Server on the 2008 R2 box, I get
(All Unassigned) and just the one internal address - none of the external
interfaces are shown.
I have to select (All Unassigned) as I cannot limit this to just one
interface as the Internet cannot connect to the internal interface.
The problem is that this causes mail to queue as it cannot be sent on two of
the external interfaces that are not for SMTP. After a few minutes, it
chooses the one interface that it can get out on.

How can I force the SMTP component to pick up the other IP addresses so that
I can pick them from the list, or can I manually edit the registry or the
metabase(?) to enter the interfaces or IP addresses to use for SMTP
communication.

HELP!

[Sanford Whiteman]

> How can I force the SMTP component to pick up the other IP addresses so
> that I can pick them from the list, or can I manually edit the registry
> or the
> metabase(?) to enter the interfaces or IP addresses to use for SMTP
> communication.

I don't have a multihomed box to test this on right now, but you can
certainly edit the metabase accordingly.

You also might alter the metrics for the ifs so that the externally
routable one is preferred.

-- Sandy

------------------------------------
Sanford Whiteman, Chief Technologist
Broadleaf Systems, a division of
Cypress Integrated Systems, Inc.
------------------------------------

[ChristianWickham]

"Sanford Whiteman" wrote:

> I don't have a multihomed box to test this on right now, but you can
> certainly edit the metabase accordingly.

How? Where? What parameters? I have never edited the Metabase before.

> You also might alter the metrics for the ifs so that the externally
> routable one is preferred.
>

That's not really an option because the other network cards are used by OCS
2007 R2, and it needs to use the correct interface for it's own initiation of
outbound traffic.

Any other ideas that might help me select the IP addresses that are not
shown in the drop-down list?

[Sanford Whiteman]

> How? Where? What parameters? I have never edited the Metabase before.

Metabase Explorer (IIS RK).

LM > SmtpSvc > (Virtual Server #) > ServerBindings

Format is as

1.2.3.4:25:

> That's not really an option because the other network cards are used by
> OCS
> 2007 R2, and it needs to use the correct interface for it's own
> initiation of
> outbound traffic.

You should realize that when you fix the inbound socket for SMTP, that
doesn't actually affect the outbound binding.

Does OCS not bind the outbound socket to a particular interface already?
If so, then changing metrics will not affect this directly bound traffic.

[ChristianWickham]

"Sanford Whiteman" wrote:

> > How? Where? What parameters? I have never edited the Metabase before.
>
> Metabase Explorer (IIS RK).
>
> LM > SmtpSvc > (Virtual Server #) > ServerBindings
>
> Format is as
>
> 1.2.3.4:25:

Thanks, that sort of helped. I stopped the IIS services, edited
c:\windows\system32\inetsrv\metabase.xml and then found "ServerBindings" and
put in the two IP addresses in the format that you recommended above (for us
it was 123.123.123.1:25: 192.168.1.5:25: - we need a space between the two
sections).
This then appeared in IIS after the restart of services.
It appears to be working now, the queues are decreasing right now.

> > That's not really an option because the other network cards are used by
> > OCS
> > 2007 R2, and it needs to use the correct interface for it's own
> > initiation of
> > outbound traffic.
>
> You should realize that when you fix the inbound socket for SMTP, that
> doesn't actually affect the outbound binding.
>
> Does OCS not bind the outbound socket to a particular interface already?
> If so, then changing metrics will not affect this directly bound traffic.
>
> -- Sandy
>

The problem with OCS 2007 R2 on 2008 is listed in this website

http://blogs.pointbridge.com/Blogs/schertz_jeff/Pages/Post.aspx?_ID=78

[Sanford Whiteman]

> Thanks, that sort of helped.

Sort of?

> it was 123.123.123.1:25: 192.168.1.5:25: - we need a space between the
> two
> sections

N.B. In Metabase Explorer, you simply add a new item using the appropriate
format. I wasn't directing you to edit the XML file directly, though of
course you can.

> The problem with OCS 2007 R2 on 2008 is listed in this website
>
> http://blogs.pointbridge.com/Blogs/schertz_jeff/Pages/Post.aspx?_ID=78

Noted. Though the author does speak of workarounds in the OCS area as
well.

I do think we are circling two separate issues. One is the SMTP response
stream -- the outbound half of a TCP session that was initiated from a
remote host to an SMTP virtual server on port 25. The other is outbound
SMTP send sessions initiated from the local box to a remote SMTP server.
The former is affected by strong host/weak host. The latter, not
directly, provided the outbound socket is created on an interface that has
both a route to the remote host and whose source IP is allowed to connect
outbound to port 25 through intermediate routers/firewalls.

I'm going to have to know more about what traffic patterns you're seeing
now.