No mail is bounced when the backend server is unavailable. Wiith milter-ahead, I use it with the backup-mx switch. If the backend mail server (be it exchange or any other) is unavailable for any reason, mail will be accepted and good mail queued for later delivery. The domain mail would still be received on the filtering server, although all addresses would be then accepted and processed normally. You'd not be able to receive email as a client, but that would be a problem with the Exchange server to be resolved. With this setup, no 5xx series errors are returned by the filtering server then the backend server is unavailable.<br>
<br><br>Chris<br><div class="gmail_extra"><br><br><div class="gmail_quote">On Sun, Nov 25, 2012 at 6:40 PM, Brian McKerr <span dir="ltr"><<a href="mailto:bmckerr@gmail.com" target="_blank">bmckerr@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Correct me if I'm wrong, but thing you have to consider with the 'milterahead' approach is that if the downstream exchange server is unavailable for some reason, you will not be able to receive any mail and emails will bounce with invalid user or some such error ?<br>
<br>I have a shell script sitting in front of my zimbra server, this script is run from cron and currently it runs every hour primarily because I rarely add new email addresses or domains. It uses ldapsearch against the zimbra server and could easily be adopted to suit AD/Exchange. It generates postfix map files for virtual_mailbox and virtual_domains.<br>
<br>Happy to share if anyone wants to help me debug it ;)<div class="HOEnZb"><div class="h5"><br><br><br><br><div class="gmail_quote">On Sat, Nov 24, 2012 at 8:05 AM, Peter Bonivart <span dir="ltr"><<a href="mailto:bonivart@opencsw.org" target="_blank">bonivart@opencsw.org</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div>On Fri, Nov 23, 2012 at 10:17 PM, Chris Stone <<a href="mailto:axisml@gmail.com" target="_blank">axisml@gmail.com</a>> wrote:<br>
> But, that would mean though that any changes to accounts on the Exchange<br>
> server(s) would not be reflected until the next time the script runs.<br>
<br>
</div>Yes, but it also means it will be more robust.<br>
<div><div><br>
/peter<br>
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