Once your ACME client tells Let’s Encrypt that the file is ready, Let’s Encrypt tries retrieving it (potentially multiple times from multiple vantage points).
If our validation checks get the right responses from your web server, the validation is considered successful and you can go on to issue your certificate.
If you want to change your DNS provider, you just need to make some small changes at your registrar.
You can have multiple TXT records in place for the same name.
It can be hard to measure this because they often also use anycast, which means multiple servers can have the same IP address, and depending on where you are in the world you might talk to a different server (and get a different answer) than Let’s Encrypt does.
The best DNS APIs provide a way for you to automatically check whether and update is fully propagated.
I have a form with a couple of buttons and I'm using j Query Validation Plugin from
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If the validation checks fail, you’ll have to try again with a new certificate.