|
North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: RFC 974 - Mail Routing and the Domain System
Michael J. Maravillo wrote: > > Hello, > > 'Just want to clarify something... is there a difference between: > > domain.com. MX 10 mx1.domain.com. > domain.com. MX 10 mx2.domain.com. > domain.com. MX 10 mx3.domain.com. > ;... > mx1.domain.com. IN A 10.0.0.1 > mx2.domain.com. IN A 10.0.0.2 > mx3.domain.com. IN A 10.0.0.3 > > and: > > domain.com. MX 10 mx.domain.com. > ;... > mx.domain.com. IN A 10.0.0.1 > mx.domain.com. IN A 10.0.0.2 > mx.domain.com. IN A 10.0.0.3 > > >From RFC 974: > > "...Note that multiple MXs may have the same preference value. In > this case, all MXs at with a given value must be tried before any of a > higher value are tried..." > > Is the behaviour the same with the round-robined configuration? My imperfect understanding of how most mail agents handle MX records is that with the first configuration, mx1 will always be tried first, followed by mx2, etc. With the second configuration, a BIND server will return the A addresses in an effectively random pattern, so load should be distributed across the 3 servers. For future reference you are better off asking at [email protected], which seems to be back up and running. Good luck, Doug -- *** Chief Operations Officer, DALnet IRC network *** "Yes, the president should resign. He has lied to the American people, time and time again, and betrayed their trust. He is no longer an effective leader. Since he has admitted guilt, there is no reason to put the American people through an impeachment. He will serve absolutely no purpose in finishing out his term; the only possible solution is for the president to save some dignity and resign." - William Jefferson Clinton, 1974
|