I created a couple of subdomain NS records pointing to a set of external DNS servers. For some reason, these only propagate to a few locations and these locations keep changing. Its not uniformly propagating. I can see this on DNS Propagation Checker - Global DNS Testing Tool. Not sure what is going on?
It’s been a couple of days since we added this. We removed and re-added again about 24 hours ago.
The main domain is elecktra.net. The subdomain is _acme-challenge.elecktra.net. The reason for adding the NS records is to validate ownership of the domain for greengeeks.com where we are hosting a WP site at content.elecktra.net so that we can add a Let’sEncrypt cert. These NS records are failing to propagate and we are unable to add the cert.