Prometheus black-box probes for all puppetmaster hosts are failing with:
```
Get "https://<IP>:<port>/puppet/v3": x509: certificate relies on legacy Common Name field, use SANs instead
```
[[ https://logstash.wikimedia.org/app/discover#/doc/0fade920-6712-11eb-8327-370b46f9e7a5/ecs-probes-1-1.11.0-7-2025.05.08?id=HE4JsZYBaJATmKuImJV- | Example ]] for Service puppetmaster1001:8141 has failed probes (http_puppetmaster1001_eqiad_wmnet_backend_https_ip6).
This appears to have started 3 days ago, and presents like a recurrence of {T373369}. However, I'm having a hard time sorting out from that task what the resolution was.
**Edit**: The "3 days ago" reported by the alerts dashboard may be spurious, as I can easily find identical failures in the Network probes logstash dashboard prior to that. In fact, I'm having difficulty finding a time when these **were not** failing.