Let’s Encrypt: Please refer to https://curl.haxx.se/libcurl/c/libcurl-errors.html for error code: 6

Today, about a nearly two weeks after making some config changes for some Let’s Encrypt certs, today I saw new-to-me messages:

[Sat Jun 13 18:46:07 UTC 2026] Renewing: 'r720-02-pg01.example.org'
[Sat Jun 13 18:46:07 UTC 2026] Renewing using Le_API=https://acme-v02.api.acmeencrypt.org/directory
[Sat Jun 13 18:46:07 UTC 2026] Please refer to https://curl.haxx.se/libcurl/c/libcurl-errors.html for error code: 6
[Sat Jun 13 18:46:07 UTC 2026] Cannot init API for: https://acme-v02.api.acmeencrypt.org/directory.
[Sat Jun 13 18:46:07 UTC 2026] Sleeping for 10 seconds and retrying.
[Sat Jun 13 18:46:17 UTC 2026] Please refer to https://curl.haxx.se/libcurl/c/libcurl-errors.html for error code: 6
[Sat Jun 13 18:46:17 UTC 2026] Cannot init API for: https://acme-v02.api.acmeencrypt.org/directory.
...

In this post:

• FreeBSD 15.0
• acme.sh-3.1.3_1

Looking up that URL, I found:

CURLE_COULDNT_RESOLVE_HOST (6)

Could not resolve host. The given remote host was not resolved.

Let’s see:

root@certs:/var/db/acme/certs # host acme-v02.api.acmeencrypt.org
Host acme-v02.api.acmeencrypt.org not found: 3(NXDOMAIN)
root@certs:/var/db/acme/certs # 

Oh.

I posted on Mastodon before proceeding. First things first. Priority matters.

Then I went into /var/db/acme/certs/r720-02-pg01.example.org/r720-02-pg01.example.org.conf and made this change:

-Le_API='https://acme-v02.api.acmeencrypt.org/directory'
+Le_API='https://acme-v02.api.letsencrypt.org/directory'

In short, acmeencrypt became letsencrypt.

I reran my cronjob. The cert renewed.

Not shown above: I ran this command to identify the files with similar problems:

root@certs:/var/db/acme/certs # joe $(grep -l acme-v02.api.acmeencrypt.org */*.conf)

Thanks for coming to my TED talk.