Authentication server IP list

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When renewing the ssl certificate, it is renewed through the letsencrypt authentication server.
I want to identify only the letsencrypt auth servers in the firewall and apply the whitelist policy.
If you have a letsencrypt authentication server IP list
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thank you

Let's Encrypt does not publish its validation servers' IP addresses:


Depending on what your whitelist policy is, you might find the dns-01 challenge more apt to your needs.


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