status check errors for secondary domain when using external DNS with @, www A records at different IP

[melato]

Description

If I use external DNS for a mailinabox secondary domain and set the @ and www A/AAAA records to a different IP than the mailinabox IP (MX) then mailinabox shows errors in the status page about.

Steps to reproduce

• Go to control panel, "Mail & Users" -> Users.
• Add a mail address for a new domain (or subdomain) that is on external DNS
• Setup the DNS records for that domain, as Main-In-A-Box wants them, except for NS and (@, www A/AAAA). You can also skip TLSA, SSHFP.
• Go to System -> TLS (SSL) certificates
• Provision the TLS certificates for that domain, by pressing the Provision button. (This gets rid of some errors/warnings).
• Add the _mta-sts TXT record in the external DNS. (Mail-In-A-Box did not show this record earlier).
• Go back to the Status Page

Result

The Status page shows three errors (not warnings).

• The nameservers set on this domain are incorrect.
• This domain should resolve to your box's IP address
• www.{DOMAIN}: This domain should resolve to your box's IP address

Expected Result

There should be no errors. There could be warnings.

Workaround

I can get rid of the errors, by setting the A record in Custom DNS, even though I'm not using the Mail-In-A-Box DNS nameserver:

• Go to control panel, System -> Custom DNS
• Set the A record for the secondary domain
• Go back to the Status Page
• Result: There are now warnings: ? The nameservers set on this domain at your domain name registrar should be... ? Web has been disabled for this domain because you have set a custom DNS record. ? A redirect from 'www.{DOMAIN}' has been disabled for this domain because you have set a custom DNS record on the www subdomain. ? This domain's DNSSEC DS record is not set. (This also appeared before).

[melato]

The workaround works because the status page checks for custom DNS settings of the @ A record uses this code: management/status_checks.py:

# Get the list of domains that we don't serve web for because of a custom CNAME/A record.
domains_with_a_records = get_domains_with_a_records(env)

management/web_update.py:

def get_domains_with_a_records(env):
	domains = set()
	dns = get_custom_dns_config(env)
	for domain, rtype, value in dns:
		if rtype == "CNAME" or (rtype in ("A", "AAAA") and value not in ("local", env['PUBLIC_IP'])):
			domains.add(domain)
	return domains

Perhaps a solution would be for get_domains_with_a_records to do a DNS query for the A record, instead of looking for custom DNS settings.

There is a related enhancement request: #404

[ttimpe]

Please, finally fix this. I've been using MIAB since the beginning and assuming that I want it to handle all of my DNS for all of my domains is just a little too much. Give me per-domain checkboxes or radioboxes. 🔘Just mail, contacts, calendar 🔘Website hosting (root domain and www should resolve to this server) 🔘Have MIAB be the primary nameserver for this domain

This would remove a lot of clutter on the status check dashboard.

[JoshData]

Really not interested in having folks demand that other contributors add new features, so I blocked @ttimpe.