This is not entirely true. Certainly the MX record points to the domain mail host, but when a host name is specified, the email goes to that host. Before I commented on this, I ran a test. blu.org is the domain I use. ;; ANSWER SECTION: blu.org. 3600 IN MX 5 asgard-usdc.blu.org. My home system is gaf.blu.org, which is a CNAME pointing to a very ugly ATTBI address. Sending email to gaf@gaf.blu.org from another system does not go through blu.org at all. The IP address will certainly come from the BLU server (or a secondary or cache). JW wrote:
All mail for a domain will be delivered to the host that is in the MX record of the domain. Sending mail to user@somecomputer.yourdomain.tld will not be directed to the computer "somecomputer", but to whatver host is in the MX record. -- Jerry Feldman <gaf@blu.org> Boston Linux and Unix user group http://www.blu.org PGP key id:C5061EA9 PGP Key fingerprint:053C 73EC 3AC1 5C44 3E14 9245 FB00 3ED5 C506 1EA9