Access registry metrics
The OpenShift Container Registry provides an endpoint for Prometheus metrics. Prometheus is a stand-alone, open source systems monitoring and alerting toolkit. The metrics get exposed at the /extensions/v2/metrics path of the registry endpoint. You can access the metrics by running a metrics query that includes a cluster role.
Procedure
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Create a cluster role if you do not already have one to access the metrics:
$ cat <<EOF | oc create -f - apiVersion: rbac.authorization.k8s.io/v1 kind: ClusterRole metadata: name: prometheus-scraper rules: - apiGroups: - image.openshift.io resources: - registry/metrics verbs: - get EOF -
Add the cluster role to a user account by entering the following command:
$ oc adm policy add-cluster-role-to-user prometheus-scraper <username> -
For the metrics query, get the user token.
openshift: $ oc whoami -t -
Run a metrics query in node or inside a pod. The following example command and output demonstrate this task.
$ curl --insecure -s -u <user>:<secret> \https://image-registry.openshift-image-registry.svc:5000/extensions/v2/metrics | grep imageregistry | head -n 20
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<user>:<secret>: The<user>object can be arbitrary, but<secret>tag must use the user token.# HELP imageregistry_build_info A metric with a constant '1' value labeled by major, minor, git commit & git version from which the image registry was built. # TYPE imageregistry_build_info gauge imageregistry_build_info{gitCommit="9f72191",gitVersion="v3.11.0+9f72191-135-dirty",major="3",minor="11+"} 1 # HELP imageregistry_digest_cache_requests_total Total number of requests without scope to the digest cache. # TYPE imageregistry_digest_cache_requests_total counter imageregistry_digest_cache_requests_total{type="Hit"} 5 imageregistry_digest_cache_requests_total{type="Miss"} 24 # HELP imageregistry_digest_cache_scoped_requests_total Total number of scoped requests to the digest cache. # TYPE imageregistry_digest_cache_scoped_requests_total counter imageregistry_digest_cache_scoped_requests_total{type="Hit"} 33 imageregistry_digest_cache_scoped_requests_total{type="Miss"} 44 # HELP imageregistry_http_in_flight_requests A gauge of requests currently being served by the registry. # TYPE imageregistry_http_in_flight_requests gauge imageregistry_http_in_flight_requests 1 # HELP imageregistry_http_request_duration_seconds A histogram of latencies for requests to the registry. # TYPE imageregistry_http_request_duration_seconds summary imageregistry_http_request_duration_seconds{method="get",quantile="0.5"} 0.01296087 imageregistry_http_request_duration_seconds{method="get",quantile="0.9"} 0.014847248 imageregistry_http_request_duration_seconds{method="get",quantile="0.99"} 0.015981195 imageregistry_http_request_duration_seconds_sum{method="get"} 12.260727916000022
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