When my host goes down I don't care too much about the website being down but moreso about my email. Is there anyway for me to have a backup email server? So that if my host goes down the mails forward to another account? I'm thinking that setting up a mydomain.com account and having their nameservers as backup would work. If my host goes down then the mydomain nameservers would forward the mail to my stable account. Would that work?
I don't have this setup or active - so take it with a grain of salt. I believe it would work, but not sure from experience.
I believe there is a way to setup your domain so that mail goes through ZoneEdit. I believe there is a way that costs one or two credits/year to have them cache mail there before it is sent to you the enduser.
I know you were looking for specifics, I don't have them. But I offer this to you to point a possible way.
That would only work for users whose ISP do not have a DNS entry for your website in their cache. If your main host goes down, new DNS requests will go to the backup name server, but the old data will still remain cached in the DNS servers of other ISPs until the information expires.
What you want to do is have two MX records set up in your zone. If the main MX fails, mail servers look at the secondary MX record.
I understood (perhaps wrongly) that email servers tried to deliver messages for X number of days? Otherwise, what are the (occasional all be it) messages all about that say your message could not be delivered at this time but the server will keep trying.. blah blah?