TLS certificate guides
Background for getting public TLS certificates under control before the shorter lifetime limits arrive.
47-Day TLS Certificates: The CA/Browser Forum SC-081 Timeline Explained
The 200, 100 and 47-day TLS certificate limits from CA/Browser Forum ballot SC-081: dates, validation reuse, why it happens and renewals per year.
Certificate Renewal Automation: A Practical ACME Guide
How to automate TLS certificate renewal with ACME: HTTP-01, DNS-01 and TLS-ALPN-01, wildcards, appliances that cannot run ACME, ARI and monitoring.
Certificate Transparency: How CT Logs Reveal Your Subdomains
How Certificate Transparency logs work, how to search them for your certificates and subdomains, what they reveal and how to keep internal names out.