IIS7 SMTP
Phil
I'm running IIS7 on Windows Server 2008
I'm wondering if the SMTP service is suitable for sending a very large
number of emails - more than 100,000 at a time?
Does anyone have experience of using the SMTP service to do this?
Thanks
Phil
Sanford Whiteman
> number of emails - more than 100,000 at a time?
>
> Does anyone have experience of using the SMTP service to do this?
Well, sure. Depends on what you mean by "at a time," of course. For one
thing, you absolutely do not want to open 100,000 concurrent outbound
connections -- and your server will be very happy that you didn't. For
another, you can't have more than 90,000 message objects at any one point
in time by default (you can change this limit, but unless you have a
vastly powerful server it is probably better to configure your application
to accept this limit). Meter the submission flow into the queue slightly,
configure queue lifetimes appropriately, and -- vitally important -- equip
your mailserver appropriately on the hardware side and you will be fine.
IIS SMTP is a powerful MTA.
-- Sandy
------------------------------------
Sanford Whiteman, Chief Technologist
Broadleaf Systems, a division of
Cypress Integrated Systems, Inc.
------------------------------------
Brian Cryer
in message news:op.u2skswgx6c17zw@gw02...
>> I'm wondering if the SMTP service is suitable for sending a very large
>> number of emails - more than 100,000 at a time?
>>
>> Does anyone have experience of using the SMTP service to do this?
>
> Well, sure. Depends on what you mean by "at a time," of course. For one
> thing, you absolutely do not want to open 100,000 concurrent outbound
> connections -- and your server will be very happy that you didn't. For
> another, you can't have more than 90,000 message objects at any one point
> in time by default (you can change this limit, but unless you have a
> vastly powerful server it is probably better to configure your application
> to accept this limit). Meter the submission flow into the queue slightly,
> configure queue lifetimes appropriately, and -- vitally important -- equip
> your mailserver appropriately on the hardware side and you will be fine.
> IIS SMTP is a powerful MTA.
The default limit for the number of outbound connections is 1000, so even if
you send 100,000 emails "at a time" you won't get 100,000 concurrent
outbound connections, only 1000 at most.
Wouldn't it be easier for the OP to simply increase the limit on the number
of messages in the message queue? As per
http://support.microsoft.com/kb/258748? That would probably be a lot easier
than implementing a second queuing mechanism. But I ought to say that I have
no experience in sending out that many emails, so I don't know what pitfalls
there might be. (Sandy, care to share your experiences?)
Its also worth pointing out that with 100,000 emails going out, there will
be quite a number of non-deliveries and bounces and that these ought to be
catered for.
--
Brian Cryer
www.cryer.co.uk/brian
Sanford Whiteman
> even if you send 100,000 emails "at a time" you won't get 100,000
> concurrent outbound connections, only 1000 at most.
Yes, that's exactly what I meant by the fluid definition of "at a time."
> Wouldn't it be easier for the OP to simply increase the limit on the
> number of messages in the message queue?
No, because if the hardware isn't up to it, all you've done is given the
false assurance of the server's capability. The default of 90,000 message
objects is extremely generous for most people who have never built
high-capacity mail servers before (RAID levels, immediate/delay queue
partitioning, RAM per message, etc.). We don't know what the hardware
capabilities are here. But until proven otherwise, it is unlikely that
the hw will be _underused_ at the 90,000 message limit. You only pump
that limit up if you can demonstrate firsthand that you have the resource
headroom.
Brian Cryer
in message news:op.u2vyttjm6c17zw@gw02...
>> The default limit for the number of outbound connections is 1000, so
>> even if you send 100,000 emails "at a time" you won't get 100,000
>> concurrent outbound connections, only 1000 at most.
>
> Yes, that's exactly what I meant by the fluid definition of "at a time."
>
>> Wouldn't it be easier for the OP to simply increase the limit on the
>> number of messages in the message queue?
>
> No, because if the hardware isn't up to it, all you've done is given the
> false assurance of the server's capability. The default of 90,000 message
> objects is extremely generous for most people who have never built
> high-capacity mail servers before (RAID levels, immediate/delay queue
> partitioning, RAM per message, etc.). We don't know what the hardware
> capabilities are here. But until proven otherwise, it is unlikely that
> the hw will be _underused_ at the 90,000 message limit. You only pump
> that limit up if you can demonstrate firsthand that you have the resource
> headroom.
Sounds reasonable. Thank you.
--
Brian Cryer
www.cryer.co.uk/brian