Router keeps retrying to transfer mail instead of bouncing "450 - User unknown in recipient table"

HCL Domino Domino Forum
1

Hi there,

I’m running Domino 6.5.1 on Windows 2000.

Whenever a user sends mail to an invalid email address nosuchuser@acme.com, router keeps retrying the message:

tell router show queue

Msgs State Via Destination

4 Retry(5) SMTP ACME.COM

Last Error: 450 nosuchuser@acme.com: User unknown in local recipient table.

Next Retry: 08/07/2004 09:30:01

…

101 WaitingForDNS Waiting for DNS availability.

Transfer Threads: Max = 25; Total = 25; Inactive = 0; Max Concurrent = 7

Delivery Threads: Max = 20; Total = 2; Inactive = 0

Why doesn’t router just bounce the message back to my Notes user, telling it the error message?

Why does it keep retrying?

Is there any way I can configure Domino to try to deliver a message, and if user doesn’t exist, bounce it back and remove it from mail.box?

Thanks,

Daniel

2

Subject: Router keeps retrying to transfer mail instead of bouncing “450 - User unknown in recipient table”

If the target domain does not exist at all then messages will bounce very quickly.

Often though a user will misadress an email to a domain which does exist, but has no MX. The Domino server will keep trying to send to these domains for 24 hours before giving up and returning the undeliverable mail to the sender.

I believe this timeout can be set to be shorter, but can’t remember how. No doubt others will pitch in.

3

Subject: It’s not a permanent error

The recipient’s server is returning a 450 error, meaning that this is a transient (ie: non-permanent) error.

Basically the other mail server is telling you that for some reason it cannot deliver the mail at this time, but may be able to deliver it at a later time. This can be due to a lot of reasons (e.g.: the recipients LDAP server is out so the mailserver cannot do any lookups).

The mail will be bounced if the recipient server is returning a 5xx code (permanent error), or if your Domino server stops trying re-delivery in case of a transient error after a pre-set amount of time (4 hours: warning sent to user that mail could not yet be delivered, 5 days: bounce permanently – not sure about these numbers though).

There’s nothing wrong with your server, but there’s something going on on the recipients side that they need to resolve.

cheers,

Bram

4

Subject: Thank you all…(Update: There’s an SPR fix on 6.5.2)

for the responses.

We’re looking into the possibility of using a relay server (Postfix) to get the messages out of the Domino system. This is a mass-mailing solution, to around 200K recipients, and at max of 25 threads, Domino currently can’t get those out the door as fast as we’d like. Hopefully using a Postfix relay will help.

We noticed that these occur mostly to servers who do exist, but:

  1. DNS servers no longer respond to them (Unknown Domain)

  2. DNS servers don’t have any MX records for the domain

  3. MX servers for domain time-out/busy (421)

My main concern is that Domino should skip these domains and try the other ones…

Thanks again for the reply. I’ll keep you posted on how the Postfix/Linux box handles work.

UPDATE

6.5.2 has a fix for the following SPR:

SPR# MDLS59VQUV - Fixed a problem which caused all mail for a destination to be placed in retry after receiving a transient error for one recipient to that destination.