I have the same issue. Do you see anything if you run kubectl get --raw /api/v1/nodes/minikube/proxy/metrics/cadvisor ?

I'm running minikube v1.34.0 and my metrics are use the above path.

If you've deployed using the k8s-monitoring helm chart, you can see a section in the alloy configmap:

    discovery.relabel "cadvisor" {
      targets = discovery.kubernetes.nodes.targets
      rule {
        replacement   = "/metrics/cadvisor"
        target_label  = "__metrics_path__"
      }
    }

which is pointing alloy at the incorrect path, kubectl get --raw metrics/cadvisor doesn't return anything.

I'm not sure if there is a way to modify this via the values file... I'm thinking of running a standalone alloy just to scrape cadvisor.