Operations | Monitoring | ITSM | DevOps | Cloud

There is a public record of every TLS certificate ever issued for your domain, and anyone can search it. Most people who run infrastructure have never heard of these certificate transparency logs. So I read our own log, and here’s what anyone could learn about CertKit from them.

You’re probably running a TLS configuration that the IETF says is “non-conformant”. But you didn’t do anything wrong. In July, the IETF published a pair of RFCs that took away three of TLS 1.2’s key exchange methods and froze the rest of it. The phrase they used is MUST NOT, the strongest thing a specification is allowed to say. Nginx, Apache, and Windows Server all ship with those key exchanges turned on by default. Nothing breaks tomorrow.

In May I wrote that you probably don’t need private PKI for internal infrastructure, because DNS validation gets a publicly trusted certificate onto hosts that never touch the internet. In June I pointed out that Apple enforces an 825-day cap on private certificates, so your own CA doesn’t even free you from the browser vendors. Two days ago I told you that public client certificates stop renewing in October, and that the replacement is a private certificate authority.

Chrome’s root program decides what certificates will be trusted by Chrome, and what they are allowed to do. Recently, Google decided that client authentication isn’t on the list. Under Chrome Root Program Policy v1.8, every certificate issued on or after March 15, 2027 can assert only one Extended Key Usage (EKU): server authentication. Let’s Encrypt moved early.

Every HTTPS connection starts with a TLS handshake. It’s the security check, answering “are you who you say you are?” and “how are we going to keep this conversation secret?”. There’s a lot going on during the handshake, and there used to be even more before it all got hacked and removed. And that’s useful to understand, the modern TLS 1.3 handshake is short because everything else got compromised.

The old deployment flow expected a lot from you. You had to know what format your certificate needed to be in. You had to know where it should be stored on the target system. Then you had to review and customize a deployment script in a code editor before anything ran. It turns out most of you don’t want to do that. And fair enough, staring at a script editor when you just want a certificate on your Exchange server is a little intimidating.

Every certificate renewal automation tool has to answer one architecture question before it does anything else: where does the private key get generated? A reader who used to be “the certificate guy” at his organization emailed me this week to ask about exactly that: It’s the right instinct. It’s also how most automation tools work. Certbot generates the key on the server, builds a certificate signing request, and the private key never leaves the machine.

How do we keep our Sonicwall certificates up to date as certificate lifetimes get shorter? We’re already at 200 day certs with 100 then 47 day certificates coming soon. A certificate you used to touch once every year now needs replacing up to twelve times a year. Doing this by hand is out of the question, no one has the time. Even if they did, the frequent updates is just asking for mistakes. Luckily, this can be automated using the SonicOS API.

On June 3, Let’s Encrypt announced that the post-quantum web is going to run on something called Merkle Tree Certificates. The internet did what it does and turned this into a doomsday Q-Day countdown. The quantum computers are coming, your certificates are about to break, panic! Unlike every other security vendor, I’m not worried about quantum computers. But the announcement is still worth your attention. Just not for the reason you’ve been told.

Most security vendors hide their documentation behind a login. Some don’t write it at all. You get a sales page, a demo, and a request to install an agent on your servers, and you’re expected to trust that the thing does what the marketing says. That’s backwards. So we wrote the docs, and we put all of them at certkit.io/docs. No login, no account gate, no “contact us for details.” You can read every page before you create an account.