On Wed, 2009-04-01 at 10:40 +0100, Peter Bowyer wrote: > 2009/4/1 Tomasz Chmielewski <[email protected]>: > > > > I know the proper way to do it would be to have an up-to-date list of > > existing users on the Exim box for all "remote users", but it's not > > always possible. > > That's a great use case for Exim's recipient callout verification. As > long as the destination server rejects unknown recipients at SMTP > time, your Exim will 'learn' (ie cache) which users are valid and > which are not and reject invalid users. > The problem then (as seen here recently) is that Exim's cache gets out of step with the recipient server. Exim then accepts the message, but the recipient server rejects it. A bounce goes back to the sender, which is what the OP was trying to avoid.
In our case we have reduced the positive cache time, but I see no way around some window of time existing in which a bounce could be sent out other than not using Exim's positive cache at all. John. -- --------------------------------------------------------------- John Horne, University of Plymouth, UK Tel: +44 (0)1752 587287 E-mail: [email protected] Fax: +44 (0)1752 587001 -- ## List details at http://lists.exim.org/mailman/listinfo/exim-users ## Exim details at http://www.exim.org/ ## Please use the Wiki with this list - http://wiki.exim.org/
