ClusterLoader：need to suport get etcd mtrics by cert file

[keontang]

I have a v1.11.2 k8s cluster with an etcd cluster which enables auth by cert file. When i run clusterloader2, EtcdMetrics measurement failed to get etcd metrics by http:

https://github.com/kubernetes/perf-tests/blob/f7ae8630a0d06f5ecd141d5d08d3bfdb9cec4e88/clusterloader2/pkg/measurement/common/etcd_metrics.go#L100

func getEtcdMetrics(provider, host string) ([]*model.Sample, error) {

	...
       cmd := "curl http://localhost:2379/metrics"
	...

}

so, i think maybe we need to suport get etcd mtrics by cert file.

[fejta-bot]

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[fejta-bot]

Stale issues rot after 30d of inactivity. Mark the issue as fresh with /remove-lifecycle rotten. Rotten issues close after an additional 30d of inactivity.

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[wojtek-t]

/remove-lifecycle rotten

[fejta-bot]

Issues go stale after 90d of inactivity. Mark the issue as fresh with /remove-lifecycle stale. Stale issues rot after an additional 30d of inactivity and eventually close.

If this issue is safe to close now please do so with /close.

Send feedback to sig-testing, kubernetes/test-infra and/or fejta. /lifecycle stale

[wojtek-t]

/remove-lifecycle stale /lifecycle frozen

[WangEP]

If you use kubeadm to build the cluster, the metric port may not 2379. In my machine, it's 2381. you can use “ps aux | grep -P '/etc[d] ' ” to get in detail( pay attention to the “--listen-metrics-urls=”)