Saving debug log to /var/log/letsencrypt/letsencrypt.log Requesting a certificate for http://mail.duckdavid.com and 4 more domains Certbot failed to authenticate some domains (authenticator: webroot). The Certificate Authority reported these problems: Domain: http://autoconfig.mail.duckdavid.com Type: dns Detail: DNS problem: SERVFAIL looking up CAA for http://duckdavid.com - the domain's nameservers may be malfunctioning Domain: http://autodiscover.mail.duckdavid.com Type: dns Detail: DNS problem: SERVFAIL looking up CAA for http://duckdavid.com - the domain's nameservers may be malfunctioning Domain: http://mail.duckdavid.com Type: dns Detail: DNS problem: SERVFAIL looking up CAA for http://duckdavid.com - the domain's nameservers may be malfunctioning Domain: http://mta-sts.mail.duckdavid.com Type: dns Detail: DNS problem: SERVFAIL looking up CAA for http://duckdavid.com - the domain's nameservers may be malfunctioning Domain: http://www.mail.duckdavid.com Type: dns Detail: DNS problem: SERVFAIL looking up CAA for http://duckdavid.com - the domain's nameservers may be malfunctioning Hint: The Certificate Authority failed to download the temporary challenge files created by Certbot. Ensure that the listed domains serve their content from the provided --webroot-path/-w and that files created there can be downloaded from the internet. Some challenges have failed. Ask for help or search for solutions at https://community.letsencrypt.org. See the logfile /var/log/letsencrypt/letsencrypt.log or re-run Certbot with -v for more details.