TLS handshake error tls: received record with version 301 when expecting version 303

Vault
,
1

We’ve been running Vault 1.11 for quite awhile on Kubernetes eks 1.22.15, we just recently started to receive this error message which we have not seen before, and believe its related to the load balancer certificate perhaps? Although the certificate is fine. Its self signed by the vault automated mechanism. We’ve looked high and low, but can not seem to find our specific error to zero in on in Vault. Hoping to see if anyone here may have run into this in their travels and working with Hashicorp Vault?

Vault TLS 2023-03-06T20:24:23.263Z [INFO] http: TLS handshake error from 10.101.12.131:45332: tls: received record with version 301 when expecting version 303

2

I believe this message means “Something tried to connect to me using TLS 1.0 but I only support TLS 1.2”.

Perhaps something on your network (e.g. a security scanner?) has started attempting to connect to your Vault using older TLS versions.

Try tracking down what that IP address is, and why it is trying to connect to Vault.