Embedded etcd monitoring

[cablespaghetti]

Currently can't monitor embedded etcd when that is enabled. When a release of k3s has been cut with this PR, we can revisit.

https://github.com/k3s-io/k3s/pull/2750

[plsnotracking]

Looks like the underlying PR has been merged, is it okay to now enable the etcd metrics?

[knweiss]

FWIW: I've just tested this successfully with k3s v1.22.6+k3s1 (stable channel).

I.e. start k3s with --etcd-expose-metrics=true and then configure the local kube-prometheus-stack-32.2.1 values.yaml to a) enable kubeEtcd b) list the IP endpoints of the k3s server nodes where embedded etcd is running and c) switch the etcd port from 2379 to 2381.

kubeEtcd:
  enabled: true

  ## If your etcd is not deployed as a pod, specify IPs it can be found on
  ##
  endpoints:
    - ...insertyourips...
    - ...insertyourips...
    - ...insertyourips...

  ## Etcd service. If using kubeEtcd.endpoints only the port and targetPort are used
  ##
  service:
    enabled: true
    port: 2381
    targetPort: 2381