Heroku自动证书管理：域名验证失败求助

Hey there, let’s walk through troubleshooting this Heroku Automated Certificate Management (ACM) validation error step by step— I’ve worked through similar issues with GoDaddy DNS before, so here’s what I’d prioritize checking:

• Match your DNS records exactly to Heroku’s requirements
  First, run heroku domains in your terminal and jot down the target value for each domain (it’ll look something like your-app-name.herokudns.com). Head over to GoDaddy’s DNS manager and verify:

  • For subdomains (e.g., www.yourdomain.com), you need a CNAME record pointing directly to that Heroku target. Avoid using A records here—Heroku’s IPs are dynamic, so A records will break validation.
  • For root domains (e.g., yourdomain.com), use an ALIAS or ANAME record (GoDaddy labels this as an "Alias" record type in their DNS tool) pointing to the Heroku target. Root domains can’t use CNAME records, so this is non-negotiable.
  • Set the record’s TTL (Time to Live) to a low value (like 300 seconds) to speed up DNS propagation—GoDaddy often defaults to longer TTLs, which can delay validation.

• Confirm DNS propagation is complete
  Even if you updated your records, DNS might not have rolled out to all global servers yet. Use terminal commands to check locally:

  • For subdomains: Run dig your-subdomain.yourdomain.com CNAME — the output should show your Heroku herokudns.com target.
  • For root domains: Run dig yourdomain.com — look for the Alias record pointing to the correct Heroku target.
    Keep in mind propagation can take up to 24 hours, but with a 300-second TTL, it’s usually much faster.

• Clear out conflicting DNS records
  GoDaddy sometimes adds default records (like A records pointing to their own hosting servers) that can conflict with your Heroku setup. Check for duplicate records for the same domain (e.g., both an A record and an Alias for your root domain) and delete any that don’t match Heroku’s requirements. Conflicting records will confuse the validation process every time.

• Re-trigger the validation workflow
  After fixing your DNS records, force Heroku to re-run the validation check by running these commands in order:

  heroku certs:auto:disable
  heroku certs:auto:enable
  

  Sometimes the initial validation attempt times out or gets stuck, and a fresh start resolves the issue.

• Double-check for domain name typos
  It sounds simple, but a tiny typo (like youdomain.com instead of yourdomain.com) between your heroku domains output and GoDaddy’s DNS setup will cause validation to fail. Cross-reference each domain name carefully.

Pro tip: If you’re using a root domain, make sure GoDaddy’s "Domain Forwarding" feature is disabled for it—this feature can override your Alias record and block Heroku’s validation checks entirely.

内容的提问来源于stack exchange，提问作者John Rogerson