Whilst trying to renew a Let’s Encrypt certificate on an older CentOS server, you might experience the following:
Cert is due for renewal, auto-renewing... Starting new HTTPS connection (1): acme-v01.api.letsencrypt.org Attempting to renew cert from /etc/letsencrypt/renewal/mail.blue-hat.co.za.conf produced an unexpected error: urn:acme:error:serverInternal :: The server experienced an internal error :: ACMEv1 is deprecated and you can no longer get certificates from this endpoint. Please use the ACMEv2 endpoint, you may need to update your ACME client software to do so. Visit https://community.letsencrypt.org/t/end-of-life-plan-for-acmev1/88430/27 for more information.. Skipping.
The problem is certbot
is outdated. Do this:
yum update certbot
Reference
yum update certbot