Hi,
I have recently deployed a test Exchange 2013 with the mailbox role and client access roll on Windows server 2012 R2
The test machine is also a DC, DNS server, DHCP Server. I have no edge transport server, the Frontend transport connector, ie SMTP service is being used.
Exchange 2013 has been updated to CU7 and windows server 2012 has all the latest updates installed from windows update.
The problem i am having is the Sender ID filter, installed with the anti-spam configuration, is running very slowly.
If i use the Test-SenderID cmdlet with any external address it can sometimes take minutes to come back with the test result.
However sometimes it comes back quite quickly - its somewhat intermittent. It doesn't matter what 'PurportedResponsibleDomain' i use or IPaddress for the test - the majority of the time its very slow, although occasionally it will come back within a second with the result, but do the same test again with the same parameters and its back to a minute or 2 again.
This slow response is replicated with a SMTP test via telnet, upon the final '.' to send the email, it can hang for a minute or 2. If i disable the SenderID filter i get the acknowledgement from the SMTP server within a second. This occurs if i telnet direct from the exchange machine, or from another machine on the network.
Things i have observed:
-After a couple of days from rebooting the server - the SenderID filter suddenly, for apparently no reason, starts responding instantly, with the Test-SenderID cmdlet consistently returing results within a second - ie problem resolved. If i reboot the server im back to the slow running.
-Internal email is being delivered fast, no delays
-External email is delayed by a minute or 2, confirmed to be caused by the SenderID filter.
Things i have checked:
-DNS configuration looks good, no problems, all Local IP's on the 1 and only adapter have A records. There is a valid MX record, external DNS records for the mail domain are correct. I have put valid SPF records for the dc domain etc.
-No errors in application logs other than the usual suspects from exchange 2013 (a few performance counter errors)
-No DNS errors or warnings in the event logs.
-InternalSMTPServers on the TransportConfig has been set to the IP assigned to the adapter. I have also tried adding all IP's on this adapter (there are 4), and even 127.0.0.1 to this InternalSMTPServers list, but it makes no difference for external mail or the Test-SenderID cmdlet. It does however speed up a telnet smtp test direct from the exchange machine as the internalSMTPServers list results in a bypass.