Mail-in-a-Box on Oracle Cloud (aarch64)

Notes for installing MiaB for a subdomain (not the root domain) on OCI’s aarch64 Ampere shape VMs:

Turn up a VM, note it’s Public IP
- Pick an Ubuntu LTS version listed at https://mailinabox.email/
- The tol only support every other LTS version, see this support thread
Set up NS records for
- Create Glue records (DNS type A for ns1.box.sub.domain.ext and ns2.box.sub.domain.ext pointing at the VM’s public IP from above)
- Create NS records for sub.domain.ext and box.sub.domain.ext pointing at ns1.box.sub.domain.ext, and ns2.box.sub.domain.ext
Login to the VM, and run curl -s https://mailinabox.email/setup.sh | sudo -E bash
Provision SSL / TLS certificates at https://box.sub.domain.ext/admin#tls
Setup a catch-all email for the domain at https://box.sub.domain.ext/admin#aliases
Setup 2-factor auth for the domain at https://box.sub.domain.ext/admin#mfa
[Optional] Setup a secondary DNS¹ using he.net
- Add ns1.he.net ns2.he.net ns3.he.net ns4.he.net ns5.he.net xfr:216.218.133.2 xfr:2001:470:600::2 into the Hostname box in the Using a secondary nameserver section at https://box.sub.domain.ext/admin#custom_dns.
- On the domain’s primary registrar, add DNS entries of type NS for sub.domain.ext pointing at ns1.he.net, ns2.he.net
- Go to https://dns.he.net > Zones > Add a new slave
- Enter sub.domain.ext for the domain, and ns1.box.sub.domain.ext as master NS