I have a paranoid client that wants emails sent to be archived at 2 servers at once. So if an email was sent to name@domain.com, that email would go to their regular mail server, and then at the same time go to a secondary mail server and stored there. I suggested doing a secondary MX record, in case the first fails, but they wanted all emails to be backed up anyway. First question is, is this even possible to do. Have mail go to 2 different servers at once. Would this be setup using 2 mail.domain.com A-records and having MX pointed to mail.domain.com? Second, what is best solution for this? It seems pointless to me to be making a backup of a server when it's working.....but nonetheless. Would it be better to setup email forwarding for every account and send it to a secondary email address? Any feedback would be highly appreciated! Thank you in advance.
I know sendmail has no such functionality in it, and I don't think any other smtp server has it either. Sendmail won't do it because of privacy issues, and that's probably the same with all the other programs. Sendmail has the new Milter API and maybe you can hack the SMFIF_ADDRCPT to duplicate the recipient and forward it to another domain, but that's the best I can think of...