Paul, it may be a worthwhile call to Microsoft Support to verify that you a) have a bug and b) don't have a different issue such as DNS. Al _____ From: paul_lemonidis@xxxxxxxxxxx [mailto:paul_lemonidis@xxxxxxxxxxx] Sent: Thursday, December 18, 2003 10:56 AM To: [ExchangeList] Subject: [exchangelist] RE: Multiple MX Records http://www.MSExchange.org/ Hi Al Many thanks for your prompt reply and help. Sorry I should have said. I am running Exchange 2003 Build 6.5.6944.0 on Windows 2003. From what you say it sounds like I may have to wait for a hotfix or service pack to resolve this? Having said that I do seem to remember we did have the problem on our old Exchange 2000 machine which had SP3 with the latest rollup package. Fortunately it is not a major problem at present. Whilst it could be me firewall my gut feeling is that it is not. Unfortunately I have no way to prove or disprove that statement at present. May thanks in advance. Regards, Paul Lemonidis. ----- Original Message ----- From: Mulnick, <mailto:Al.Mulnick@xxxxxxxxxx> Al To: [ExchangeList] <mailto:exchangelist@xxxxxxxxxxxxx> Sent: Thursday, December 18, 2003 1:51 PM Subject: [exchangelist] RE: Multiple MX Records http://www.MSExchange.org/ <http://www.MSExchange.org/> If I recall correctly, there was an issue similar to this that was fixed in later releases. The problem was with the underlying SMTP (I think; it's been some time). What versions of OS and app are you running? The issue was something to do with the way the SMTP service would use MX records. It was very similar to what you describe. _____ From: paul_lemonidis@xxxxxxxxxxx [mailto:paul_lemonidis@xxxxxxxxxxx] Sent: Thursday, December 18, 2003 8:31 AM To: [ExchangeList] Subject: [exchangelist] Multiple MX Records http://www.MSExchange.org/ Hi All Has anyone else come across this one? I have outbound messages queued up for domains where there primary server is down. These queue up and are not delivered which would seem fair enough on the face of it. Just one problem the destination system has multiple MX records and the other hosts are up. Why does Exchange refuse to use them? Even if I force the connection they do not leave? Eventually they go of their own accord but this takes several minutes or even hours? I cannot say at this stage if this is as a result of the primary server coming back on line. I suspect it is. > server 217.20.32.36 Default Server: ns1.lon.ipmh.telecity.net Address: 217.20.32.36 > set q=mx > mtsn.org.uk Server: ns1.lon.ipmh.telecity.net Address: 217.20.32.36 Non-authoritative answer: mtsn.org.uk MX preference = 10, mail exchanger = scanmailext.easymail.va.ifl .net mtsn.org.uk MX preference = 20, mail exchanger = mx1.easymail.va.ifl.net mtsn.org.uk MX preference = 30, mail exchanger = mx2.easymail.va.ifl.net mtsn.org.uk nameserver = dns2.rmplc.co.uk mtsn.org.uk nameserver = dns0.rmplc.co.uk mtsn.org.uk nameserver = dns1.rmplc.co.uk scanmailext.easymail.va.ifl.net internet address = 213.18.255.195 mx1.easymail.va.ifl.net internet address = 213.18.248.112 mx2.easymail.va.ifl.net internet address = 213.18.248.112 > I can telnet the second server just fine. The first one drops the connection almost immediately. I suspect that is the answer? I am guessing that since it does make a connection of sorts, albeit very briefly, it never tries the second record as it thinks it is connected and thus never checks the other MX records. Above and below are relevant screen shots. 421 SMTP service not available, closing transmission channel Connection to host lost. Can someone tell me if I am correct and if there is any way around this please. I know that strictly speaking, if my theory is correct, it could be classed as a firewall issue at the remote end but that doesn't help me deliver mail. The only short term way I see around this is to set up an extra Virtual SMTP server and restrict the address space to just that domain and forward to the second record host explicitly rather than using DNS. Although that won't help with the trapped messages I suspect? Any ideas, comments or suggestions please? Many thanks in advance, Regards, Paul Lemonidis. ------------------------------------------------------ List Archives: http://www.webelists.com/cgi/lyris.pl?enter=exchangelist Exchange Newsletters: http://www.msexchange.org/pages/newsletter.asp Exchange FAQ: http://www.msexchange.org/pages/larticle.asp?type=FAQ ------------------------------------------------------ Other Internet Software Marketing Sites: Leading Network Software Directory: http://www.serverfiles.com No.1 ISA Server Resource Site: http://www.isaserver.org Windows Security Resource Site: http://www.windowsecurity.com/ Network Security Library: http://www.secinf.net/ Windows 2000/NT Fax Solutions: http://www.ntfaxfaq.com ------------------------------------------------------ ------------------------------------------------------ List Archives: http://www.webelists.com/cgi/lyris.pl?enter=exchangelist Exchange Newsletters: http://www.msexchange.org/pages/newsletter.asp Exchange FAQ: http://www.msexchange.org/pages/larticle.asp?type=FAQ ------------------------------------------------------ Other Internet Software Marketing Sites: Leading Network Software Directory: http://www.serverfiles.com No.1 ISA Server Resource Site: http://www.isaserver.org Windows Security Resource Site: http://www.windowsecurity.com/ Network Security Library: http://www.secinf.net/ Windows 2000/NT Fax Solutions: http://www.ntfaxfaq.com ------------------------------------------------------ ------------------------------------------------------ List Archives: http://www.webelists.com/cgi/lyris.pl?enter=exchangelist Exchange Newsletters: http://www.msexchange.org/pages/newsletter.asp Exchange FAQ: http://www.msexchange.org/pages/larticle.asp?type=FAQ ------------------------------------------------------ Other Internet Software Marketing Sites: Leading Network Software Directory: http://www.serverfiles.com No.1 ISA Server Resource Site: http://www.isaserver.org Windows Security Resource Site: http://www.windowsecurity.com/ Network Security Library: http://www.secinf.net/ Windows 2000/NT Fax Solutions: http://www.ntfaxfaq.com ------------------------------------------------------