Use your box’s DNS API to set custom DNS records on domains hosted here. For instance, you can create your own dynamic DNS service

can someone explain furth what this means:

Use your box’s DNS API to set custom DNS records on domains hosted here. For instance, you can create your own dynamic DNS service.

Have you seen the Custom DNS page in the admin interface?

Yes, of course. I have 2 boxes running. one external dns (fwla.com) and one custom dns (ucamg.com)

I was looking for a little more clarity of the sentence. I think it indicates that I can use it for sub-domains to act more like Route53 or the domain info section at the registrar for sub-domains (and the main domain too). I’ve almost considered moving fwla.com (currently using Route53 even though registrar is godaddy) to do all the route53 stuff. I’ve just been concerned about all the customization I have going with the DNS.

On the customDNS box, I want to host mail for additional domains and so think this option is suggesting just that.

Is there ANY additional information about what is implied in this sentence that i’ve missed?

I don’t know what sort of additional information you’re looking for. That sentence and the API docs look straightforward to me.

To host mail for another domain, just create an alias.