[Building Sakai] mail sending failures - greylisting

[Matthew Buckett]

On Thu, Mar 12, 2009 at 10:59 AM, Steve Swinsburg
<s.swinsburg at lancaster.ac.uk> wrote:
> Hi all,
> I am getting the following errors when sending mail from within Sakai,
> either via Site Info > Add Participants, or via the Mailtool:
> Failed to send email.
> Error message: Sending failed; nested exception is: class
> javax.mail.SendFailedException: Invalid Addresses;
> nested exception is: class javax.mail.SendFailedException: 451 4.7.1
> Greylisting in action, please come back in 00:10:00
> I've never seen this before. the email addresses I am supplying are valid
> and varied (ie not all the same domain), but it returns this error so
> quickly that I think it's something to do with the mail setup on this end,
> not the receiving end.
>
> Anyone know what the go is here?

Shot in the dark...

We at one point had problems with outbound mails getting rejected
because we weren't giving a valid SMTP HELO command, I didn't track
down what was causing this but just forced javax.mail to use a good
hostname.

http://jira.sakaiproject.org/jira/browse/SAK-11775

Now we run a SMTP server on localhost and sakai just delivers to
localhost which then forwards all the mail to our institutional
servers. This is much more robust generally (once setup).

-- 
  Matthew Buckett