# 2021-09-17-16:33:45+0800 Fix generate alertmanager cert false alert

- Cause: `alertmanager cert expire alert`
- Operation:
Alert-manager already use `letsencrypt-generated-alertmanager-operated-tls` cert, we can remove this secret.
```
kubectl delete secret letsencrypt-generated-alertmanager-tls -n monitoring
```
- Impact: `NONE`
- Recovery operation: `NONE`
- Time window: `2021-09-17-16:33:45+0800 ~ 2021-09-17-16:40:45+0800`