How to verify certificate renewal actually worked
On May 21, 2019, LinkedIn’s URL shortener went down. The certificate had expired. Millions of people cried out in terror when they couldn’t click on AI link bait. The interesting part: LinkedIn had renewed the certificate ten days earlier. The renewal succeeded. The certificate just never made it to the server. The renewed cert existed somewhere, but the server still served the old one. Most certificate automation is built to prevent the “I forgot to renew” problem.