> my MX record and then in my A record add "backup.mydomain.com" to point > to the RCN static IP? I would set that up with a higher priority number > so it only gets accessed when my primary MX record (which points to my > Covad IP) is down. Would that work?
For inbound, yes, since MX failover is built in to the MX algorithm). The bigger problem is outbound mail. Even if you manage to get working dead gateway detection so that outbound packets go out your RCN link if Covad is down (many cheapish routers can make sure this part works), you have to make sure that the mailserver's public IP on the RCN link has a PTR record matching its HELO -- and that PTR can't be in a known subscriber range or have be a suspicious subscriber-like hostname (1-2-3-4-cable-consumer.rcn.net). If you can get the PTR-EHLO-A "roundtrip" working on your backup link so you can have reliable outbound delivery in a failover state, then you should be okay. As Darin said, this does not account for any attempt to balance inbound HTTP over the 2 links; if you can automate DNS updates (by running your own DNS, or at least your own stealth primary DNS) this can, albeit roughly, be accomplished. And I don't disagree with the recommendation of just moving anything this sensitive to a datacenter! :) But there are indeed ways of getting it done at home in a rough sense for a few $ (dual-WAN router, Draytek for example). Just a matter of how much energy you want to spend, and what kind of guarantees you can make to your clients. --Sandy ------------------------------------ Sanford Whiteman, Chief Technologist Broadleaf Systems, a division of Cypress Integrated Systems, Inc. e-mail: sa...@cypressintegrated.com SpamAssassin plugs into Declude! http://www.imprimia.com/products/software/freeutils/SPAMC32/download/release/ Defuse Dictionary Attacks: Turn Exchange or IMail mailboxes into IMail Aliases! http://www.imprimia.com/products/software/freeutils/exchange2aliases/download/release/ http://www.imprimia.com/products/software/freeutils/ldap2aliases/download/release/ To Unsubscribe: http://imailserver.com/support/discussion_list/ List Archive: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ Knowledge Base/FAQ: http://imailserver.com/support/kb.html