I am confused as to how alerts are processed in SharePoint Foundation 2010.
I have 3 virtual machines currently running in my test environment, plus a laptop with Win7 on it.
One virtual machine has Server 2008 R2 with SharePoint Foundation 2010 and SQL Express installed. Another virtual machine has Server 2008 R2 and is a domain controller and my DNS server. The third virtual machine is a dedicated mail server running FreeBSD and postfix. No Exchange server running.
My Win7 laptop has Outlook 2010 installed and fetches mail from the FreeBSD server.
I've been doing some work with email enabled lists and alerts from lists, all using Outlook on the Win7 machine to test. At one point, my alerts stopped working. That issue has since been fixed, but now I am curious, based on a little further testing, how my alerts are getting through.
SharePoint is configured to use the SMTP server on the box where it is installed for outgoing email. However, during some investigative work, I disabled the SMTP virtual server from the IIS 6.0 management interface and I disabled the SMTP service running on that machine. With both these disabled, the alerts are still being processed and arriving at my Win7 Outlook inbox.
Checking the SharePoint logs, I don't see the alert job running as I did when troubleshooting the inital problem of alerts not being processed (turned out to be a corrupted entry in the ImmedSubscription table in the site's content database where the alert was created).
Any ideas of how SharePoint is sending out the alerts with (as far as I can tell) SMTP services disabled on the box?
I've created a test message RFC-882 format and put it into the Pickup folder, and it's still sitting there. Plus trying to telnet to port 25 of the server also isn't working. Both those tell me that SMTP on the box is down right now - again, as I intended.
Thanks in advance.