Yeah they chose a weird way of preventing people from sending mail to that server. Blocking port 25 is so much easier.
Sincerely, Andrey Fyodorov Systems Engineer Messaging and Collaboration Spherion -----Original Message----- From: Dean Cunningham [mailto:[EMAIL PROTECTED] Sent: Monday, September 08, 2003 8:41 PM To: Exchange Discussions Subject: Re: Delivery to Alternate MX Records IMNSHO their logic is screwed. The MX records work as follows Get me a list of MX records for the domain seanet.com [done] Can I connect to highest priority MX record ? Yes = try and send the email No = try next MX record Under Yes, if having trouble sending email , exchange server retries but because server can always connect to highest priority MX record, it will keep choosing to use that one until the message holding peroid for your exchange server times it out and sends the message back to the server. The people at seanet.com need to block port 25 for their server with the highest priority MX record. this will then force the exchange server to use the next available MX record. Whilst not exactly explained see ftp://ftp.rfc-editor.org/in-notes/rfc2821.txt and http://www.rfc-editor.org for a 452 error your sherver should be (and is ) reacting as follows 4yz Transient Negative Completion reply The command was not accepted, and the requested action did not occur. However, the error condition is temporary and the action may be requested again. The sender should return to the beginning of the command sequence (if any). It is difficult to assign a meaning to "transient" when two different sites (receiver- and sender-SMTP agents) must agree on the interpretation. Each reply in this category might have a different time value, but the SMTP client is encouraged to try again. A rule of thumb to determine whether a reply fits into the 4yz or the 5yz category (see below) is that replies are 4yz if they can be successful if repeated without any change in command form or in properties of the sender or receiver (that is, the command is repeated identically and the receiver does not put up a new implementation.) cheers dean >>> [EMAIL PROTECTED] 9/09/2003 11:28:04 a.m. >>> Hi All, I'm a bit puzzled by something and I'm hoping that someone can help out. There's a particular domain, seanet.com, that we can't send messages to at the moment. Any message sent to this domain hangs in the IMC queue with the error, 452 4.3.0 Cannot write message to disk. According to this ISP's support group they've recently reconfigured their main mail server so it can no longer receive messages from the outside world, and I assume that the error we're seeing is a result of this reconfiguration. They further claim that our server should try to deliver messages to their second or third mail server, something it definitely isn't doing. So here are my questions. Should an Exchange server (5.5, by the way) try the next MX record after getting a 452 from the primary server, and are there any settings in Exchange that affect this behavior? As an additional philosophical question, does it strike anyone else as strange that they should deliberately put an essentially malfunctioning server at the address of their first MX record in the name of spam fighting and security? -Peter ********************************************************************** Northland State of the Environment Report 2002 now online at www.nrc.govt.nz ********************************************************************** NORTHLAND REGIONAL COUNCIL This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify [EMAIL PROTECTED] ********************************************************************** _________________________________________________________________ List posting FAQ: http://www.swinc.com/resource/exch_faq.htm Web Interface: http://intm-dl.sparklist.com/cgi-bin/lyris.pl?enter=exchange&text_mode=&; lang=english To unsubscribe: mailto:[EMAIL PROTECTED] Exchange List admin: [EMAIL PROTECTED] _________________________________________________________________ List posting FAQ: http://www.swinc.com/resource/exch_faq.htm Web Interface: http://intm-dl.sparklist.com/cgi-bin/lyris.pl?enter=exchange&text_mode=&lang=english To unsubscribe: mailto:[EMAIL PROTECTED] Exchange List admin: [EMAIL PROTECTED]
