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ACME challenge validation

ACME challenge validation is a mechanism used by Certificate Authorities (CAs), such as Let's Encrypt, to verify that an applicant controls the domain for which a certificate is requested.^[free-domain.md]

Validation Methods

The validation process typically involves proving ownership of the domain by responding to a challenge issued by the CA.

  • HTTP Challenge: The CA expects a specific file to be accessible at a standard path on the web server. The default path utilized is EXAMPLE.COM/.well-known/acme-challenge/.^[free-domain.md]
  • DNS Challenge: The CA expects a specific DNS TXT record to be created for the domain. For instance, a validation path might look like http://www.yudady.tk/.well-known/pki-validation/10A01C0C743DA31E6706682CF9257B37.txt.^[free-domain.md]

Tools and Automation

The certbot tool is commonly used to automate the request and validation process for obtaining SSL certificates^[free-domain.md].

Sources

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