kube_inventory

Kubernetes Inventory Input Plugin

This plugin generates metrics derived from the state of the following Kubernetes resources:

• daemonsets
• deployments
• endpoints
• ingress
• nodes
• persistentvolumes
• persistentvolumeclaims
• pods (containers)
• services
• statefulsets

Kubernetes is a fast moving project, with a new minor release every 3 months. As such, we will aim to maintain support only for versions that are supported by the major cloud providers; this is roughly 4 release / 2 years.

This plugin supports Kubernetes 1.11 and later.

Series Cardinality Warning

This plugin may produce a high number of series which, when not controlled for, will cause high load on your database. Use the following techniques to avoid cardinality issues:

• Use metric filtering options to exclude unneeded measurements and tags.
• Write to a database with an appropriate retention policy.
• Consider using the Time Series Index.
• Monitor your databases series cardinality.
• Consult the InfluxDB documentation for the most up-to-date techniques.

Configuration:

[[inputs.kube_inventory]]
  ## URL for the Kubernetes API
  url = "https://$HOSTIP:6443"

  ## Namespace to use. Set to "" to use all namespaces.
  # namespace = "default"

  ## Use bearer token for authorization. ('bearer_token' takes priority)
  ## If both of these are empty, we'll use the default serviceaccount:
  ## at: /run/secrets/kubernetes.io/serviceaccount/token
  # bearer_token = "/path/to/bearer/token"
  ## OR
  # bearer_token_string = "abc_123"

  ## Set response_timeout (default 5 seconds)
  # response_timeout = "5s"

  ## Optional Resources to exclude from gathering
  ## Leave them with blank with try to gather everything available.
  ## Values can be - "daemonsets", deployments", "endpoints", "ingress", "nodes",
  ## "persistentvolumes", "persistentvolumeclaims", "pods", "services", "statefulsets"
  # resource_exclude = [ "deployments", "nodes", "statefulsets" ]

  ## Optional Resources to include when gathering
  ## Overrides resource_exclude if both set.
  # resource_include = [ "deployments", "nodes", "statefulsets" ]

  ## selectors to include and exclude as tags.  Globs accepted.
  ## Note that an empty array for both will include all selectors as tags
  ## selector_exclude overrides selector_include if both set.
  selector_include = []
  selector_exclude = ["*"]

  ## Optional TLS Config
  ## Trusted root certificates for server
  # tls_ca = "/path/to/cafile"
  ## Used for TLS client certificate authentication
  # tls_cert = "/path/to/certfile"
  ## Used for TLS client certificate authentication
  # tls_key = "/path/to/keyfile"
  ## Use TLS but skip chain & host verification
  # insecure_skip_verify = false

  ## Uncomment to remove deprecated metrics.
  # fielddrop = ["terminated_reason"]

Kubernetes Permissions

If using RBAC authorization, you will need to create a cluster role to list "persistentvolumes" and "nodes". You will then need to make an aggregated ClusterRole that will eventually be bound to a user or group.

---
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: influx:cluster:viewer
  labels:
    rbac.authorization.k8s.io/aggregate-view-telegraf: "true"
rules:
  - apiGroups: [""]
    resources: ["persistentvolumes", "nodes"]
    verbs: ["get", "list"]

---
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: influx:telegraf
aggregationRule:
  clusterRoleSelectors:
    - matchLabels:
        rbac.authorization.k8s.io/aggregate-view-telegraf: "true"
    - matchLabels:
        rbac.authorization.k8s.io/aggregate-to-view: "true"
rules: [] # Rules are automatically filled in by the controller manager.

Bind the newly created aggregated ClusterRole with the following config file, updating the subjects as needed.

---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: influx:telegraf:viewer
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: influx:telegraf
subjects:
  - kind: ServiceAccount
    name: telegraf
    namespace: default

Quickstart in k3s

When monitoring k3s server instances one can re-use already generated administration token. This is less secure than using the more restrictive dedicated telegraf user but more convienient to set up.

# an empty token will make telegraf use the client cert/key files instead
$ touch /run/telegraf-kubernetes-token
# replace `telegraf` with the user the telegraf process is running as
$ install -o telegraf -m400 /var/lib/rancher/k3s/server/tls/client-admin.crt /run/telegraf-kubernetes-cert
$ install -o telegraf -m400 /var/lib/rancher/k3s/server/tls/client-admin.key /run/telegraf-kubernetes-key

[kube_inventory]
bearer_token = "/run/telegraf-kubernetes-token"
tls_cert = "/run/telegraf-kubernetes-cert"
tls_key = "/run/telegraf-kubernetes-key"

Metrics:

• kubernetes_daemonset
  • tags:
    • daemonset_name
    • namespace
    • selector (*varies)
  • fields:
    • generation
    • current_number_scheduled
    • desired_number_scheduled
    • number_available
    • number_misscheduled
    • number_ready
    • number_unavailable
    • updated_number_scheduled

• kubernetes_deployment
  • tags:
    • deployment_name
    • namespace
    • selector (*varies)
  • fields:
    • replicas_available
    • replicas_unavailable
    • created

• kubernetes_endpoints
  • tags:
    • endpoint_name
    • namespace
    • hostname
    • node_name
    • port_name
    • port_protocol
    • kind (*varies)
  • fields:
    • created
    • generation
    • ready
    • port

• kubernetes_ingress
  • tags:
    • ingress_name
    • namespace
    • hostname
    • ip
    • backend_service_name
    • path
    • host
  • fields:
    • created
    • generation
    • backend_service_port
    • tls

• kubernetes_node
  • tags:
    • node_name
  • fields:
    • capacity_cpu_cores
    • capacity_millicpu_cores
    • capacity_memory_bytes
    • capacity_pods
    • allocatable_cpu_cores
    • allocatable_millicpu_cores
    • allocatable_memory_bytes
    • allocatable_pods

• kubernetes_persistentvolume
  • tags:
    • pv_name
    • phase
    • storageclass
  • fields:
    • phase_type (int, see below)

• kubernetes_persistentvolumeclaim
  • tags:
    • pvc_name
    • namespace
    • phase
    • storageclass
    • selector (*varies)
  • fields:
    • phase_type (int, see below)

• kubernetes_pod_container
  • tags:
    • container_name
    • namespace
    • node_name
    • pod_name
    • node_selector (*varies)
    • phase
    • state
    • readiness
  • fields:
    • restarts_total
    • state_code
    • state_reason
    • phase_reason
    • terminated_reason (string, deprecated in 1.15: use state_reason instead)
    • resource_requests_millicpu_units
    • resource_requests_memory_bytes
    • resource_limits_millicpu_units
    • resource_limits_memory_bytes

• kubernetes_service
  • tags:
    • service_name
    • namespace
    • port_name
    • port_protocol
    • external_name
    • cluster_ip
    • selector (*varies)
  • fields
    • created
    • generation
    • port
    • target_port

• kubernetes_statefulset
  • tags:
    • statefulset_name
    • namespace
    • selector (*varies)
  • fields:
    • created
    • generation
    • replicas
    • replicas_current
    • replicas_ready
    • replicas_updated
    • spec_replicas
    • observed_generation

pv phase_type

The persistentvolume "phase" is saved in the phase tag with a correlated numeric field called phase_type corresponding with that tag value.

Tag value	Corresponding field value
bound	0
failed	1
pending	2
released	3
available	4
unknown	5

pvc phase_type

The persistentvolumeclaim "phase" is saved in the phase tag with a correlated numeric field called phase_type corresponding with that tag value.

Tag value	Corresponding field value
bound	0
lost	1
pending	2
unknown	3

Example Output:

kubernetes_configmap,configmap_name=envoy-config,namespace=default,resource_version=56593031 created=1544103867000000000i 1547597616000000000
kubernetes_daemonset,daemonset_name=telegraf,selector_select1=s1,namespace=logging number_unavailable=0i,desired_number_scheduled=11i,number_available=11i,number_misscheduled=8i,number_ready=11i,updated_number_scheduled=11i,created=1527758699000000000i,generation=16i,current_number_scheduled=11i 1547597616000000000
kubernetes_deployment,deployment_name=deployd,selector_select1=s1,namespace=default replicas_unavailable=0i,created=1544103082000000000i,replicas_available=1i 1547597616000000000
kubernetes_node,node_name=ip-172-17-0-2.internal allocatable_pods=110i,capacity_memory_bytes=128837533696,capacity_pods=110i,capacity_cpu_cores=16i,allocatable_cpu_cores=16i,allocatable_memory_bytes=128732676096 1547597616000000000
kubernetes_persistentvolume,phase=Released,pv_name=pvc-aaaaaaaa-bbbb-cccc-1111-222222222222,storageclass=ebs-1-retain phase_type=3i 1547597616000000000
kubernetes_persistentvolumeclaim,namespace=default,phase=Bound,pvc_name=data-etcd-0,selector_select1=s1,storageclass=ebs-1-retain phase_type=0i 1547597615000000000
kubernetes_pod,namespace=default,node_name=ip-172-17-0-2.internal,pod_name=tick1 last_transition_time=1547578322000000000i,ready="false" 1547597616000000000
kubernetes_service,cluster_ip=172.29.61.80,namespace=redis-cache-0001,port_name=redis,port_protocol=TCP,selector_app=myapp,selector_io.kompose.service=redis,selector_role=slave,service_name=redis-slave created=1588690034000000000i,generation=0i,port=6379i,target_port=0i 1547597616000000000
kubernetes_pod_container,container_name=telegraf,namespace=default,node_name=ip-172-17-0-2.internal,node_selector_node-role.kubernetes.io/compute=true,pod_name=tick1,phase=Running,state=running,readiness=ready resource_requests_cpu_units=0.1,resource_limits_memory_bytes=524288000,resource_limits_cpu_units=0.5,restarts_total=0i,state_code=0i,state_reason="",phase_reason="",resource_requests_memory_bytes=524288000 1547597616000000000
kubernetes_statefulset,namespace=default,selector_select1=s1,statefulset_name=etcd replicas_updated=3i,spec_replicas=3i,observed_generation=1i,created=1544101669000000000i,generation=1i,replicas=3i,replicas_current=3i,replicas_ready=3i 1547597616000000000