OCI: Secure Load Balancer
It started as a routine wildcard certificate renewal and updating on the Oracle Cloud Infrastructure. It usually takes about 20 minutes, but not today when the certbot offered me a private key update.
I spent most of those twenty minutes remembering how to update wildcard certificates and why the Load balancer states no certificates are configured. Today it started with a private key update offer, presumably, a smart move in the pre-quantum computing era.
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I went through the steps and got my new certificate and key pair. The next step is to create a new load balancer certificate (I don't think regular certificates are allowed on always-free accounts) and instruct the secure listener to use it.
The result was disappointing, and the site threw the error below without reason.
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The OpenSSL has no problem with the certificate and private key but threw the "handshake failure" on the load balancer port. The answer was in the listener configuration.
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Open listener for edit (three dots on the right), and expand the Advanced Options section. Select the predefined oci-modern-ssl-cipher-suite-v1 or create a custom set of ciphers that meet your security policies.
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Save the changes and give it a few seconds to propagate the changes. No,w the site is available, and the browser has no issues with the protocols and ciphers.
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To summarize: if you make significant certificate changes, ensure that your infrastructure is ready.