Trouble with Multi-Level Subdomain DNS

[tech22]

Hi, I run a website with an example.com.au structure and just set up a subdomain:
green.example.com.au and am getting a “This site can’t be reached” error.

I added the correct IPV4 and IPV6 A and AAAA records but this hasn’t fixed the problem.

I’m aware that multi-level subdomains do not work on Cloudflare - would this url be considered a multi-level subdomain that wouldn’t work on CF?

[fritex]

Hm, do you mean like:

• [example.com]
  • [c.example.com]
    • [b.c.example.com]
      • [a.b.c.example.com]

Could be some limitations due to an SSL as written here:

Origin Certificates and Subdomains

The help portion which references *.secure.example.com is in the origin certificate help. Origin certificates are used for the securing of connections between Cloudflare and the origin. Origin certificates are not signed by a public CA and aren’t trusted by end user browsers. They are intended to provide validation for secure authentication between Cloudflare and the server where the content resides (and re installed and configured on those origin servers). The certificates which are presented …

Moreover, are you using Flexible or do you already have SSL certificate at your origin for the desired sub-domains, meaning that you use Full SSL at Cloudflare?

If not, I beleive you would need to pay $10 for a dedicated SSL certificate at Cloudflare or to be on the Business Plan so you could import your SSL certificate that covers all of them and have it resolved successfully.

Double level sub domain

@user220, Universal SSL only covers the root domain and has a first level wildcard. For the second level you would need a certificate which explicitly covers that host or which is a wildcard for the first level host *.testing.example.com which would cover abc. and bcd.testing.example.com. The $10 option is a SAN cert which would allow you to define up to 50 hostnames. So you could have testing, *.testing (counts as 2 host names on SAN cert) and development and *.development as well as …

[sdayman]

No, that shouldn’t be. You can tell if it fails that test if you see two subdomain levels in that DNS record: