If I were to add the following records to my domain host, what would happen if one host (220.127.116.11 for example) was down?
MX @ mail.mydomain.com
A mail 18.104.22.168
A mail 22.214.171.124
I want to setup our only mail server so that if our ISP goes down (which it has 2 times this week), that I can move the cable over to our other ISP and mail will continue flowing by switching from the 126.96.36.199 WAN IP to the 188.8.131.52 WAN IP.
If I do it this way, would this cause intermittent problems where it does a round-robin and the mail server answers incoming 50% of the time, or will it work like having 2 MX records and just jump to the next one if the first one doesn't answer?
Right now, I have it setup as the following which is working fine. The annoying thing is that people have to access OWA now as mail2, which we would rather have both working as just mail.
MX @ mail.mydomain.com pref 10
MX @ mail2.mydomain.com pref 20
A mail 184.108.40.206
A mail2 220.127.116.11