10-21-2009 08:15 PM
We have particular email host we seem to be having problems sending to. I am pretty sure its something o their end. But I am providing info from our Mail Flow Central logs. There is one that I don't believe I've seen before. Does anyone know what this means?
Date:
October 20, 2009 10:15:06 -0500
Last state:
Message successfully delivered to '<user>@<domain>.com' at 'xx.xxx.xx.xx'. Response: ''possible delivery''
:?
10-29-2009 06:04 PM
This was obtained from the Support Portal knowledge base. Hopefully it helps.
What does the "Possible Delivery" feature do?
http://tinyurl.com/28zqcq
+++
What does the "Possible Delivery" feature do?
When the Possible Delivery feature is enabled, AsyncOS treats any
message as a "possible delivery" if it times out after the body of the message is delivered, but
before the recipient host acknowledges receipt of the message.
This functionality prevents recipients from
receiving multiple copies of a message if continuous errors at their
recipient host prevent acknowledgement of receipt. AsyncOS logs this
recipient as a possible delivery in the mail logs and counts the message
as completed.
The timeout is a TCP timeout; normally 4 minutes. SMTP will timeout before 4 minutes.
If this feature is disabled, the Email Security Appliance (ESA) will try to resend the message. If the feature is enabled, the message is seen as delivered.
++++
We have particular email host we seem to be having problems sending to. I am pretty sure its something o their end. But I am providing info from our Mail Flow Central logs. There is one that I don't believe I've seen before. Does anyone know what this means?
Date:
October 20, 2009 10:15:06 -0500
Last state:
Message successfully delivered to '@ .com' at 'xx.xxx.xx.xx'. Response: ''possible delivery''
:?
12-17-2015 11:28 AM
So, should this feature even be enabled? The User Guide states the following. Yet, it seems to be the recommended setting.
"If you enable this feature, message delivery will not be reliable and may lead to loss of messages. Also, your appliance will not be RFC 5321-compliant. For more information, see http://tools.ietf.org/html/rfc5321#section-6.1."
12-17-2015 08:13 PM
Hey Tim,
This is my 2cents
But I'd suggest not to have it enabled, this feature was put forward in older releases for the servers who needed mass mailing to be done and did not want to keep queues are a very high level while waiting for the final 220 message accepted message.
Feature catered to large mass mailing services.
Regards,
Matthew
12-18-2015 11:41 AM
Thank you, Mathew. TAC also recommended disabling it.
11-05-2009 02:51 PM
Thanks! that makes sense. There seems to be some "network" issue between us, and this domain...
Discover and save your favorite ideas. Come back to expert answers, step-by-step guides, recent topics, and more.
New here? Get started with these tips. How to use Community New member guide