Throughout our family we run a number of Yunohosts. Lacking IPv4 addresses, some of them run at this or that home, some run on VPS’s. They run different domains (some YNH just a single domain, others more than one).
Sometimes the homeserved Yunohosts are unable to receive email, eg, when I break the router by accident.
With not all mailservers seeing a lot of traffic, it is not always directly clear that there is a problem.
I would like to have redundant mail servers outside the house, for example using one of the mailservers of the externally hosted Yunohosts. A separate VPS would be an option as well, but in that case I’d like it to be a backup mailserver for multiple Yunohosts.
The standard way, I think, would be to have multiple MX records, with multiple mail servers.
How would I go about that? I would prefer to keep hosting mail services within Yunohost. One of the obstacles I see is that the pointer / reverse DNS would not match multiple mail domains (already worrying me with multiple domains on a single YNH at the moment, rightfully so?)
Thanks in advance for your suggestions!