On 5/18/2004 6:44 PM, Per Gregers Bilse wrote:
For a long time since then, backup MXs have been seen as a kind of value-added courtesy service; they serve no really useful purpose
well, they're handy for centralizing filters against multiple domains, if you're willing to put your various primaries at the mercy of the filter service, and if the filter knows your valid recipients. what with ldap-smart servers and fancy routing, this isn't even hard anymore. but general "backup" MX is long-time dead. first the spammers killed our outbound flexibility by forcing everybody to close their relays, and then they killed our inbound flexibility by forcing everybody to close their generic backup MX paths. that cracking sound is stress fractures as the network gets more rigid. -- Eric A. Hall http://www.ehsco.com/ Internet Core Protocols http://www.oreilly.com/catalog/coreprot/