On 2008-12-27, Sahil Tandon <sa...@tandon.net> wrote: > jk...@kinz.org wrote: >> >>> [...] you do not need an MX record to send or receive mail. >> >> True, but many email systems will no longer accept email that >> comes from a system/address with no valid MX record. Yet another >> spam defense technique. As a result, if you don't have an MX >> record much of your mail may be rejected, so these days having an >> MX record is "almost" a requirement. > > This is also false.
I used to have mail rejected because the sending domain didn't have an MX record. After I set up my MX record, those systems that used to reject mail started to accept mail. > Sending email from a domain without an MX record is perfectly > acceptable. That depends. Some mail servers accept it, soem don't. > And, when you receive email from most major mailers (i.e. > gmail), the connecting system is not a valid MX. I'm not sure what you mean by the phrase "the connecting system is not a valid MX". The requirement in question is that the sending domain has an MX record -- I don't think it has anything to do with the connecting client machine. > If a real SMTP client attempts to send email to domainX, it > will first look up the MX and try sending there; if there is > no MX record, then the mail is directed at the A record. This > is all governed by RFCs. Can you give an example of a > legitimate SMTP server out there that rejects email based > solely on the fact that it comes from a domain with no MX > record? It used to happen to me regularly, but I don't run my own mail server any more. > I am sure some people do this, but I'd be surprised if it were > as prevalent as you suggest. Back when I ran a mail server, I would have guessed that 5-10% of servers required that the sending domain have an MX record. -- Grant
