At this point I would say "yes", and not just for MCI. Many administrators are requiring RDNS (most notable AOL) these days as a first-line anti-spam measure. I telnetted into MCI's smtp box from a machine with no public RDNS info, and noticed that MCI checks recipient names during the smtp conversation. It verified that it was a valid address (or gave me "eye candy" that looked like it had), took the entire conversation, and then bounced it within 30 seconds or so with the same "no such recipient" message as you'd received. Then I sent an email to that recipient from my mail server, which does have properly configured RDNS in the public zone files, and it hasn't bounced yet. But I've only given it five minutes, and I asked that user to please respond to me if they receive the email. Is it a known live user?
-tom -----Original Message----- From: Tener, Richard [mailto:[EMAIL PROTECTED]] Posted At: Friday, April 19, 2002 12:50 PM Posted To: MSExchange Mailing List Conversation: custom recipient Subject: RE: custom recipient so tom for mci to work on my system i need a reverse lookup zone -----Original Message----- From: Tom Meunier [mailto:[EMAIL PROTECTED]] Sent: Friday, April 19, 2002 1:38 PM To: Exchange Discussions Subject: RE: custom recipient It means that (in this PARTICULAR case, anyway) your DNS isn't properly set up. It would appear that MCImail.com has begun requiring valid reverse DNS lookup before allowing SMTP communications. I hope you don't pay your DNS guy as much as you pay your antivirus guy. C:\>nslookup -q=mx midship.com Server: Address: midship.com MX preference = 10, mail exchanger = smtp.midship.com smtp.midship.com internet address = 12.39.69.130 C:\>nslookup -q=ptr 12.39.69.130 Server: Address: *** dns1.courts.state.tx.us can't find 130.69.39.12.in-addr.arpa.: Non-existent domain -----Original Message----- From: Tener, Richard [mailto:[EMAIL PROTECTED]] Posted At: Friday, April 19, 2002 12:26 PM Posted To: MSExchange Mailing List Conversation: custom recipient Subject: custom recipient Does anyone know why this would happen we had a custom recipeint on our server that has been working all this time until today. I verified with mci that it is not on their end so it must be on my end. Does anyone know what invalid_ip_status means. Thanks Rich Your message did not reach some or all of the intended recipients. Subject: test from logistics Sent: 4/19/02 1:19 PM The following recipient(s) could not be reached: [EMAIL PROTECTED] on 4/19/02 1:19 PM The recipient name is not recognized The MTS-ID of the original message is: c=US;a= ;p=Mid Ship;l=LOGISTICS1-020419171913Z-2794 MSEXCH:IMS:Mid Ship:Logistics:LOGISTICS1 3550 (000B09AA) 550 5.7.1 550 Invalid_IP_Status: [EMAIL PROTECTED] _________________________________________________________________ List posting FAQ: http://www.swinc.com/resource/exch_faq.htm Archives: http://www.swynk.com/sitesearch/search.asp To unsubscribe: mailto:[EMAIL PROTECTED] Exchange List admin: [EMAIL PROTECTED] _________________________________________________________________ List posting FAQ: http://www.swinc.com/resource/exch_faq.htm Archives: http://www.swynk.com/sitesearch/search.asp To unsubscribe: mailto:[EMAIL PROTECTED] Exchange List admin: [EMAIL PROTECTED] _________________________________________________________________ List posting FAQ: http://www.swinc.com/resource/exch_faq.htm Archives: http://www.swynk.com/sitesearch/search.asp To unsubscribe: mailto:[EMAIL PROTECTED] Exchange List admin: [EMAIL PROTECTED]
