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Kubelet Configuration (v1beta1)

Resource Types

KubeletConfiguration

KubeletConfiguration contains the configuration for the Kubelet

FieldDescription
apiVersion
string
kubelet.config.k8s.io/v1beta1
kind
string
KubeletConfiguration
enableServer [Required]
bool

enableServer enables Kubelet's secured server. Note: Kubelet's insecure port is controlled by the readOnlyPort option. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may disrupt components that interact with the Kubelet server. Default: true

staticPodPath
string

staticPodPath is the path to the directory containing local (static) pods to run, or the path to a single static pod file. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that the set of static pods specified at the new path may be different than the ones the Kubelet initially started with, and this may disrupt your node. Default: ""

syncFrequency
meta/v1.Duration

syncFrequency is the max period between synchronizing running containers and config. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that shortening this duration may have a negative performance impact, especially as the number of Pods on the node increases. Alternatively, increasing this duration will result in longer refresh times for ConfigMaps and Secrets. Default: "1m"

fileCheckFrequency
meta/v1.Duration

fileCheckFrequency is the duration between checking config files for new data. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that shortening the duration will cause the Kubelet to reload local Static Pod configurations more frequently, which may have a negative performance impact. Default: "20s"

httpCheckFrequency
meta/v1.Duration

httpCheckFrequency is the duration between checking http for new data. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that shortening the duration will cause the Kubelet to poll staticPodURL more frequently, which may have a negative performance impact. Default: "20s"

staticPodURL
string

staticPodURL is the URL for accessing static pods to run. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that the set of static pods specified at the new URL may be different than the ones the Kubelet initially started with, and this may disrupt your node. Default: ""

staticPodURLHeader
map[string][]string

staticPodURLHeader is a map of slices with HTTP headers to use when accessing the podURL. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may disrupt the ability to read the latest set of static pods from StaticPodURL. Default: nil

address
string

address is the IP address for the Kubelet to serve on (set to 0.0.0.0 for all interfaces). If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may disrupt components that interact with the Kubelet server. Default: "0.0.0.0"

port
int32

port is the port for the Kubelet to serve on. The port number must be between 1 and 65535, inclusive. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may disrupt components that interact with the Kubelet server. Default: 10250

readOnlyPort
int32

readOnlyPort is the read-only port for the Kubelet to serve on with no authentication/authorization. The port number must be between 1 and 65535, inclusive. Setting this field to 0 disables the read-only service. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may disrupt components that interact with the Kubelet server. Default: 0 (disabled)

tlsCertFile
string

tlsCertFile is the file containing x509 Certificate for HTTPS. (CA cert, if any, concatenated after server cert). If tlsCertFile and tlsPrivateKeyFile are not provided, a self-signed certificate and key are generated for the public address and saved to the directory passed to the Kubelet's --cert-dir flag. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may disrupt components that interact with the Kubelet server. Default: ""

tlsPrivateKeyFile
string

tlsPrivateKeyFile is the file containing x509 private key matching tlsCertFile. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may disrupt components that interact with the Kubelet server. Default: ""

tlsCipherSuites
[]string

tlsCipherSuites is the list of allowed cipher suites for the server. Values are from tls package constants (https://golang.org/pkg/crypto/tls/#pkg-constants). If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may disrupt components that interact with the Kubelet server. Default: nil

tlsMinVersion
string

tlsMinVersion is the minimum TLS version supported. Values are from tls package constants (https://golang.org/pkg/crypto/tls/#pkg-constants). If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may disrupt components that interact with the Kubelet server. Default: ""

rotateCertificates
bool

rotateCertificates enables client certificate rotation. The Kubelet will request a new certificate from the certificates.k8s.io API. This requires an approver to approve the certificate signing requests. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that disabling it may disrupt the Kubelet's ability to authenticate with the API server after the current certificate expires. Default: false

serverTLSBootstrap
bool

serverTLSBootstrap enables server certificate bootstrap. Instead of self signing a serving certificate, the Kubelet will request a certificate from the 'certificates.k8s.io' API. This requires an approver to approve the certificate signing requests (CSR). The RotateKubeletServerCertificate feature must be enabled when setting this field. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that disabling it will stop the renewal of Kubelet server certificates, which can disrupt components that interact with the Kubelet server in the long term, due to certificate expiration. Default: false

authentication
KubeletAuthentication

authentication specifies how requests to the Kubelet's server are authenticated. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may disrupt components that interact with the Kubelet server. Defaults: anonymous: enabled: false webhook: enabled: true cacheTTL: "2m"

authorization
KubeletAuthorization

authorization specifies how requests to the Kubelet's server are authorized. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may disrupt components that interact with the Kubelet server. Defaults: mode: Webhook webhook: cacheAuthorizedTTL: "5m" cacheUnauthorizedTTL: "30s"

registryPullQPS
int32

registryPullQPS is the limit of registry pulls per second. The value must not be a negative number. Setting it to 0 means no limit. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may impact scalability by changing the amount of traffic produced by image pulls. Default: 5

registryBurst
int32

registryBurst is the maximum size of bursty pulls, temporarily allows pulls to burst to this number, while still not exceeding registryPullQPS. The value must not be a negative number. Only used if registryPullQPS is greater than 0. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may impact scalability by changing the amount of traffic produced by image pulls. Default: 10

eventRecordQPS
int32

eventRecordQPS is the maximum event creations per second. If 0, there is no limit enforced. The value cannot be a negative number. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may impact scalability by changing the amount of traffic produced by event creations. Default: 5

eventBurst
int32

eventBurst is the maximum size of a burst of event creations, temporarily allows event creations to burst to this number, while still not exceeding eventRecordQPS. This field canot be a negative number and it is only used when eventRecordQPS > 0. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may impact scalability by changing the amount of traffic produced by event creations. Default: 10

enableDebuggingHandlers
bool

enableDebuggingHandlers enables server endpoints for log access and local running of containers and commands, including the exec, attach, logs, and portforward features. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that disabling it may disrupt components that interact with the Kubelet server. Default: true

enableContentionProfiling
bool

enableContentionProfiling enables lock contention profiling, if enableDebuggingHandlers is true. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that enabling it may carry a performance impact. Default: false

healthzPort
int32

healthzPort is the port of the localhost healthz endpoint (set to 0 to disable). A valid number is between 1 and 65535. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may disrupt components that monitor Kubelet health. Default: 10248

healthzBindAddress
string

healthzBindAddress is the IP address for the healthz server to serve on. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may disrupt components that monitor Kubelet health. Default: "127.0.0.1"

oomScoreAdj
int32

oomScoreAdj is The oom-score-adj value for kubelet process. Values must be within the range [-1000, 1000]. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may impact the stability of nodes under memory pressure. Default: -999

clusterDomain
string

clusterDomain is the DNS domain for this cluster. If set, kubelet will configure all containers to search this domain in addition to the host's search domains. Dynamic Kubelet Config (deprecated): Dynamically updating this field is not recommended, as it should be kept in sync with the rest of the cluster. Default: ""

clusterDNS
[]string

clusterDNS is a list of IP addresses for the cluster DNS server. If set, kubelet will configure all containers to use this for DNS resolution instead of the host's DNS servers. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that changes will only take effect on Pods created after the update. Draining the node is recommended before changing this field. Default: nil

streamingConnectionIdleTimeout
meta/v1.Duration

streamingConnectionIdleTimeout is the maximum time a streaming connection can be idle before the connection is automatically closed. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may impact components that rely on infrequent updates over streaming connections to the Kubelet server. Default: "4h"

nodeStatusUpdateFrequency
meta/v1.Duration

nodeStatusUpdateFrequency is the frequency that kubelet computes node status. If node lease feature is not enabled, it is also the frequency that kubelet posts node status to master. Note: When node lease feature is not enabled, be cautious when changing the constant, it must work with nodeMonitorGracePeriod in nodecontroller. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may impact node scalability, and also that the node controller's nodeMonitorGracePeriod must be set to N*NodeStatusUpdateFrequency, where N is the number of retries before the node controller marks the node unhealthy. Default: "10s"

nodeStatusReportFrequency
meta/v1.Duration

nodeStatusReportFrequency is the frequency that kubelet posts node status to master if node status does not change. Kubelet will ignore this frequency and post node status immediately if any change is detected. It is only used when node lease feature is enabled. nodeStatusReportFrequency's default value is 5m. But if nodeStatusUpdateFrequency is set explicitly, nodeStatusReportFrequency's default value will be set to nodeStatusUpdateFrequency for backward compatibility. Default: "5m"

nodeLeaseDurationSeconds
int32

nodeLeaseDurationSeconds is the duration the Kubelet will set on its corresponding Lease. NodeLease provides an indicator of node health by having the Kubelet create and periodically renew a lease, named after the node, in the kube-node-lease namespace. If the lease expires, the node can be considered unhealthy. The lease is currently renewed every 10s, per KEP-0009. In the future, the lease renewal interval may be set based on the lease duration. The field value must be greater than 0. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that decreasing the duration may reduce tolerance for issues that temporarily prevent the Kubelet from renewing the lease (e.g. a short-lived network issue). Default: 40

imageMinimumGCAge
meta/v1.Duration

imageMinimumGCAge is the minimum age for an unused image before it is garbage collected. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may trigger or delay garbage collection, and may change the image overhead on the node. Default: "2m"

imageGCHighThresholdPercent
int32

imageGCHighThresholdPercent is the percent of disk usage after which image garbage collection is always run. The percent is calculated by dividing this field value by 100, so this field must be between 0 and 100, inclusive. When specified, the value must be greater than imageGCLowThresholdPercent. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may trigger or delay garbage collection, and may change the image overhead on the node. Default: 85

imageGCLowThresholdPercent
int32

imageGCLowThresholdPercent is the percent of disk usage before which image garbage collection is never run. Lowest disk usage to garbage collect to. The percent is calculated by dividing this field value by 100, so the field value must be between 0 and 100, inclusive. When specified, the value must be less than imageGCHighThresholdPercent. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may trigger or delay garbage collection, and may change the image overhead on the node. Default: 80

volumeStatsAggPeriod
meta/v1.Duration

volumeStatsAggPeriod is the frequency for calculating and caching volume disk usage for all pods. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that shortening the period may carry a performance impact. Default: "1m"

kubeletCgroups
string

kubeletCgroups is the absolute name of cgroups to isolate the kubelet in Dynamic Kubelet Config (deprecated): This field should not be updated without a full node reboot. It is safest to keep this value the same as the local config. Default: ""

systemCgroups
string

systemCgroups is absolute name of cgroups in which to place all non-kernel processes that are not already in a container. Empty for no container. Rolling back the flag requires a reboot. The cgroupRoot must be specified if this field is not empty. Dynamic Kubelet Config (deprecated): This field should not be updated without a full node reboot. It is safest to keep this value the same as the local config. Default: ""

cgroupRoot
string

cgroupRoot is the root cgroup to use for pods. This is handled by the container runtime on a best effort basis. Dynamic Kubelet Config (deprecated): This field should not be updated without a full node reboot. It is safest to keep this value the same as the local config. Default: ""

cgroupsPerQOS
bool

cgroupsPerQOS enable QoS based CGroup hierarchy: top level CGroups for QoS classes and all Burstable and BestEffort Pods are brought up under their specific top level QoS CGroup. Dynamic Kubelet Config (deprecated): This field should not be updated without a full node reboot. It is safest to keep this value the same as the local config. Default: true

cgroupDriver
string

cgroupDriver is the driver kubelet uses to manipulate CGroups on the host (cgroupfs or systemd). Dynamic Kubelet Config (deprecated): This field should not be updated without a full node reboot. It is safest to keep this value the same as the local config. Default: "cgroupfs"

cpuManagerPolicy
string

cpuManagerPolicy is the name of the policy to use. Requires the CPUManager feature gate to be enabled. Dynamic Kubelet Config (deprecated): This field should not be updated without a full node reboot. It is safest to keep this value the same as the local config. Default: "None"

cpuManagerPolicyOptions
map[string]string

cpuManagerPolicyOptions is a set of key=value which allows to set extra options to fine tune the behaviour of the cpu manager policies. Requires both the "CPUManager" and "CPUManagerPolicyOptions" feature gates to be enabled. Dynamic Kubelet Config (beta): This field should not be updated without a full node reboot. It is safest to keep this value the same as the local config. Default: nil

cpuManagerReconcilePeriod
meta/v1.Duration

cpuManagerReconcilePeriod is the reconciliation period for the CPU Manager. Requires the CPUManager feature gate to be enabled. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that shortening the period may carry a performance impact. Default: "10s"

memoryManagerPolicy
string

memoryManagerPolicy is the name of the policy to use by memory manager. Requires the MemoryManager feature gate to be enabled. Dynamic Kubelet Config (deprecated): This field should not be updated without a full node reboot. It is safest to keep this value the same as the local config. Default: "none"

topologyManagerPolicy
string

topologyManagerPolicy is the name of the topology manager policy to use. Valid values include:

  • restricted: kubelet only allows pods with optimal NUMA node alignment for requested resources;
  • best-effort: kubelet will favor pods with NUMA alignment of CPU and device resources;
  • none: kubelet has no knowledge of NUMA alignment of a pod's CPU and device resources.
  • single-numa-node: kubelet only allows pods with a single NUMA alignment of CPU and device resources.

Policies other than "none" require the TopologyManager feature gate to be enabled. Dynamic Kubelet Config (deprecated): This field should not be updated without a full node reboot. It is safest to keep this value the same as the local config. Default: "none"

topologyManagerScope
string

topologyManagerScope represents the scope of topology hint generation that topology manager requests and hint providers generate. Valid values include:

  • container: topology policy is applied on a per-container basis.
  • pod: topology policy is applied on a per-pod basis.

"pod" scope requires the TopologyManager feature gate to be enabled. Default: "container"

qosReserved
map[string]string

qosReserved is a set of resource name to percentage pairs that specify the minimum percentage of a resource reserved for exclusive use by the guaranteed QoS tier. Currently supported resources: "memory" Requires the QOSReserved feature gate to be enabled. Dynamic Kubelet Config (deprecated): This field should not be updated without a full node reboot. It is safest to keep this value the same as the local config. Default: nil

runtimeRequestTimeout
meta/v1.Duration

runtimeRequestTimeout is the timeout for all runtime requests except long running requests - pull, logs, exec and attach. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may disrupt components that interact with the Kubelet server. Default: "2m"

hairpinMode
string

hairpinMode specifies how the Kubelet should configure the container bridge for hairpin packets. Setting this flag allows endpoints in a Service to loadbalance back to themselves if they should try to access their own Service. Values:

  • "promiscuous-bridge": make the container bridge promiscuous.
  • "hairpin-veth": set the hairpin flag on container veth interfaces.
  • "none": do nothing.

Generally, one must set --hairpin-mode=hairpin-veth to achieve hairpin NAT, because promiscuous-bridge assumes the existence of a container bridge named cbr0. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may require a node reboot, depending on the network plugin. Default: "promiscuous-bridge"

maxPods
int32

maxPods is the maximum number of Pods that can run on this Kubelet. The value must be a non-negative integer. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that changes may cause Pods to fail admission on Kubelet restart, and may change the value reported in Node.Status.Capacity[v1.ResourcePods], thus affecting future scheduling decisions. Increasing this value may also decrease performance, as more Pods can be packed into a single node. Default: 110

podCIDR
string

podCIDR is the CIDR to use for pod IP addresses, only used in standalone mode. In cluster mode, this is obtained from the control plane. Dynamic Kubelet Config (deprecated): This field should always be set to the empty default. It should only set for standalone Kubelets, which cannot use Dynamic Kubelet Config. Default: ""

podPidsLimit
int64

podPidsLimit is the maximum number of PIDs in any pod. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that lowering it may prevent container processes from forking after the change. Default: -1

resolvConf
string

resolvConf is the resolver configuration file used as the basis for the container DNS resolution configuration. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that changes will only take effect on Pods created after the update. Draining the node is recommended before changing this field. If set to the empty string, will override the default and effectively disable DNS lookups. Default: "/etc/resolv.conf"

runOnce
bool

runOnce causes the Kubelet to check the API server once for pods, run those in addition to the pods specified by static pod files, and exit. Default: false

cpuCFSQuota
bool

cpuCFSQuota enables CPU CFS quota enforcement for containers that specify CPU limits. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that disabling it may reduce node stability. Default: true

cpuCFSQuotaPeriod
meta/v1.Duration

cpuCFSQuotaPeriod is the CPU CFS quota period value, cpu.cfs_period_us. The value must be between 1 us and 1 second, inclusive. Requires the CustomCPUCFSQuotaPeriod feature gate to be enabled. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that limits set for containers will result in different cpu.cfs_quota settings. This will trigger container restarts on the node being reconfigured. Default: "100ms"

nodeStatusMaxImages
int32

nodeStatusMaxImages caps the number of images reported in Node.status.images. The value must be greater than -2. Note: If -1 is specified, no cap will be applied. If 0 is specified, no image is returned. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that different values can be reported on node status. Default: 50

maxOpenFiles
int64

maxOpenFiles is Number of files that can be opened by Kubelet process. The value must be a non-negative number. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may impact the ability of the Kubelet to interact with the node's filesystem. Default: 1000000

contentType
string

contentType is contentType of requests sent to apiserver. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may impact the ability for the Kubelet to communicate with the API server. If the Kubelet loses contact with the API server due to a change to this field, the change cannot be reverted via dynamic Kubelet config. Default: "application/vnd.kubernetes.protobuf"

kubeAPIQPS
int32

kubeAPIQPS is the QPS to use while talking with kubernetes apiserver. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may impact scalability by changing the amount of traffic the Kubelet sends to the API server. Default: 5

kubeAPIBurst
int32

kubeAPIBurst is the burst to allow while talking with kubernetes API server. This field cannot be a negative number. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may impact scalability by changing the amount of traffic the Kubelet sends to the API server. Default: 10

serializeImagePulls
bool

serializeImagePulls when enabled, tells the Kubelet to pull images one at a time. We recommend not changing the default value on nodes that run docker daemon with version < 1.9 or an Aufs storage backend. Issue #10959 has more details. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may impact the performance of image pulls. Default: true

evictionHard
map[string]string

evictionHard is a map of signal names to quantities that defines hard eviction thresholds. For example: {"memory.available": "300Mi"}. To explicitly disable, pass a 0% or 100% threshold on an arbitrary resource. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may trigger or delay Pod evictions. Default: memory.available: "100Mi" nodefs.available: "10%" nodefs.inodesFree: "5%" imagefs.available: "15%"

evictionSoft
map[string]string

evictionSoft is a map of signal names to quantities that defines soft eviction thresholds. For example: {"memory.available": "300Mi"}. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may trigger or delay Pod evictions, and may change the allocatable reported by the node. Default: nil

evictionSoftGracePeriod
map[string]string

evictionSoftGracePeriod is a map of signal names to quantities that defines grace periods for each soft eviction signal. For example: {"memory.available": "30s"}. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may trigger or delay Pod evictions. Default: nil

evictionPressureTransitionPeriod
meta/v1.Duration

evictionPressureTransitionPeriod is the duration for which the kubelet has to wait before transitioning out of an eviction pressure condition. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that lowering it may decrease the stability of the node when the node is overcommitted. Default: "5m"

evictionMaxPodGracePeriod
int32

evictionMaxPodGracePeriod is the maximum allowed grace period (in seconds) to use when terminating pods in response to a soft eviction threshold being met. This value effectively caps the Pod's terminationGracePeriodSeconds value during soft evictions. Note: Due to issue #64530, the behavior has a bug where this value currently just overrides the grace period during soft eviction, which can increase the grace period from what is set on the Pod. This bug will be fixed in a future release. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that lowering it decreases the amount of time Pods will have to gracefully clean up before being killed during a soft eviction. Default: 0

evictionMinimumReclaim
map[string]string

evictionMinimumReclaim is a map of signal names to quantities that defines minimum reclaims, which describe the minimum amount of a given resource the kubelet will reclaim when performing a pod eviction while that resource is under pressure. For example: {"imagefs.available": "2Gi"}. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may change how well eviction can manage resource pressure. Default: nil

podsPerCore
int32

podsPerCore is the maximum number of pods per core. Cannot exceed maxPods. The value must be a non-negative integer. If 0, there is no limit on the number of Pods. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that changes may cause Pods to fail admission on Kubelet restart, and may change the value reported in Node.status.capacity.pods, thus affecting future scheduling decisions. Increasing this value may also decrease performance, as more Pods can be packed into a single node. Default: 0

enableControllerAttachDetach
bool

enableControllerAttachDetach enables the Attach/Detach controller to manage attachment/detachment of volumes scheduled to this node, and disables kubelet from executing any attach/detach operations. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that changing which component is responsible for volume management on a live node may result in volumes refusing to detach if the node is not drained prior to the update, and if Pods are scheduled to the node before the volumes.kubernetes.io/controller-managed-attach-detach annotation is updated by the Kubelet. In general, it is safest to leave this value set the same as local config. Default: true

protectKernelDefaults
bool

protectKernelDefaults, if true, causes the Kubelet to error if kernel flags are not as it expects. Otherwise the Kubelet will attempt to modify kernel flags to match its expectation. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that enabling it may cause the Kubelet to crash-loop if the Kernel is not configured as Kubelet expects. Default: false

makeIPTablesUtilChains
bool

makeIPTablesUtilChains, if true, causes the Kubelet ensures a set of iptables rules are present on host. These rules will serve as utility rules for various components, e.g. kube-proxy. The rules will be created based on iptablesMasqueradeBit and iptablesDropBit. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that disabling it will prevent the Kubelet from healing locally misconfigured iptables rules. Default: true

iptablesMasqueradeBit
int32

iptablesMasqueradeBit is the bit of the iptables fwmark space to mark for SNAT. Values must be within the range [0, 31]. Must be different from other mark bits. Warning: Please match the value of the corresponding parameter in kube-proxy. TODO: clean up IPTablesMasqueradeBit in kube-proxy. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it needs to be coordinated with other components, like kube-proxy, and the update will only be effective if MakeIPTablesUtilChains is enabled. Default: 14

iptablesDropBit
int32

iptablesDropBit is the bit of the iptables fwmark space to mark for dropping packets. Values must be within the range [0, 31]. Must be different from other mark bits. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it needs to be coordinated with other components, like kube-proxy, and the update will only be effective if MakeIPTablesUtilChains is enabled. Default: 15

featureGates
map[string]bool

featureGates is a map of feature names to bools that enable or disable experimental features. This field modifies piecemeal the built-in default values from "k8s.io/kubernetes/pkg/features/kube_features.go". If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider the documentation for the features you are enabling or disabling. While we encourage feature developers to make it possible to dynamically enable and disable features, some changes may require node reboots, and some features may require careful coordination to retroactively disable. Default: nil

failSwapOn
bool

failSwapOn tells the Kubelet to fail to start if swap is enabled on the node. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that setting it to true will cause the Kubelet to crash-loop if swap is enabled. Default: true

memorySwap
MemorySwapConfiguration

memorySwap configures swap memory available to container workloads.

containerLogMaxSize
string

containerLogMaxSize is a quantity defining the maximum size of the container log file before it is rotated. For example: "5Mi" or "256Ki". If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may trigger log rotation. Default: "10Mi"

containerLogMaxFiles
int32

containerLogMaxFiles specifies the maximum number of container log files that can be present for a container. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that lowering it may cause log files to be deleted. Default: 5

configMapAndSecretChangeDetectionStrategy
ResourceChangeDetectionStrategy

configMapAndSecretChangeDetectionStrategy is a mode in which ConfigMap and Secret managers are running. Valid values include:

  • Get: kubelet fetches necessary objects directly from the API server;
  • Cache: kubelet uses TTL cache for object fetched from the API server;
  • Watch: kubelet uses watches to observe changes to objects that are in its interest.

Default: "Watch"

systemReserved
map[string]string

systemReserved is a set of ResourceName=ResourceQuantity (e.g. cpu=200m,memory=150G) pairs that describe resources reserved for non-kubernetes components. Currently only cpu and memory are supported. See http://kubernetes.io/docs/user-guide/compute-resources for more detail. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may not be possible to increase the reserved resources, because this requires resizing cgroups. Always look for a NodeAllocatableEnforced event after updating this field to ensure that the update was successful. Default: nil

kubeReserved
map[string]string

kubeReserved is a set of ResourceName=ResourceQuantity (e.g. cpu=200m,memory=150G) pairs that describe resources reserved for kubernetes system components. Currently cpu, memory and local storage for root file system are supported. See https://kubernetes.io/docs/concepts/configuration/manage-resources-containers/ for more details. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may not be possible to increase the reserved resources, because this requires resizing cgroups. Always look for a NodeAllocatableEnforced event after updating this field to ensure that the update was successful. Default: nil

reservedSystemCPUs [Required]
string

The reservedSystemCPUs option specifies the CPU list reserved for the host level system threads and kubernetes related threads. This provide a "static" CPU list rather than the "dynamic" list by systemReserved and kubeReserved. This option does not support systemReservedCgroup or kubeReservedCgroup.

showHiddenMetricsForVersion
string

showHiddenMetricsForVersion is the previous version for which you want to show hidden metrics. Only the previous minor version is meaningful, other values will not be allowed. The format is <major>.<minor>, e.g.: 1.16. The purpose of this format is make sure you have the opportunity to notice if the next release hides additional metrics, rather than being surprised when they are permanently removed in the release after that. Default: ""

systemReservedCgroup
string

systemReservedCgroup helps the kubelet identify absolute name of top level CGroup used to enforce systemReserved compute resource reservation for OS system daemons. Refer to Node Allocatable doc for more information. Dynamic Kubelet Config (deprecated): This field should not be updated without a full node reboot. It is safest to keep this value the same as the local config. Default: ""

kubeReservedCgroup
string

kubeReservedCgroup helps the kubelet identify absolute name of top level CGroup used to enforce KubeReserved compute resource reservation for Kubernetes node system daemons. Refer to Node Allocatable doc for more information. Dynamic Kubelet Config (deprecated): This field should not be updated without a full node reboot. It is safest to keep this value the same as the local config. Default: ""

enforceNodeAllocatable
[]string

This flag specifies the various Node Allocatable enforcements that Kubelet needs to perform. This flag accepts a list of options. Acceptable options are none, pods, system-reserved and kube-reserved. If none is specified, no other options may be specified. When system-reserved is in the list, systemReservedCgroup must be specified. When kube-reserved is in the list, kubeReservedCgroup must be specified. This field is supported only when cgroupsPerQOS is set to true. Refer to Node Allocatable for more information. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that removing enforcements may reduce the stability of the node. Alternatively, adding enforcements may reduce the stability of components which were using more than the reserved amount of resources; for example, enforcing kube-reserved may cause Kubelets to OOM if it uses more than the reserved resources, and enforcing system-reserved may cause system daemons to OOM if they use more than the reserved resources. Default: ["pods"]

allowedUnsafeSysctls
[]string

A comma separated whitelist of unsafe sysctls or sysctl patterns (ending in *). Unsafe sysctl groups are kernel.shm*, kernel.msg*, kernel.sem, fs.mqueue.*, and net.*. For example: "kernel.msg*,net.ipv4.route.min_pmtu" Default: []

volumePluginDir
string

volumePluginDir is the full path of the directory in which to search for additional third party volume plugins. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that changing the volumePluginDir may disrupt workloads relying on third party volume plugins. Default: "/usr/libexec/kubernetes/kubelet-plugins/volume/exec/"

providerID
string

providerID, if set, sets the unique ID of the instance that an external provider (i.e. cloudprovider) can use to identify a specific node. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may impact the ability of the Kubelet to interact with cloud providers. Default: ""

kernelMemcgNotification
bool

kernelMemcgNotification, if set, instructs the the kubelet to integrate with the kernel memcg notification for determining if memory eviction thresholds are exceeded rather than polling. If DynamicKubeletConfig (deprecated; default off) is on, when dynamically updating this field, consider that it may impact the way Kubelet interacts with the kernel. Default: false

logging [Required]
LoggingConfiguration

logging specifies the options of logging. Refer to Logs Options for more information. Default: Format: text

enableSystemLogHandler
bool

enableSystemLogHandler enables system logs via web interface host:port/logs/ Default: true

shutdownGracePeriod
meta/v1.Duration

shutdownGracePeriod specifies the total duration that the node should delay the shutdown and total grace period for pod termination during a node shutdown. Default: "0s"

shutdownGracePeriodCriticalPods
meta/v1.Duration

shutdownGracePeriodCriticalPods specifies the duration used to terminate critical pods during a node shutdown. This should be less than shutdownGracePeriod. For example, if shutdownGracePeriod=30s, and shutdownGracePeriodCriticalPods=10s, during a node shutdown the first 20 seconds would be reserved for gracefully terminating normal pods, and the last 10 seconds would be reserved for terminating critical pods. Default: "0s"

shutdownGracePeriodByPodPriority
[]ShutdownGracePeriodByPodPriority

shutdownGracePeriodByPodPriority specifies the shutdown grace period for Pods based on their associated priority class value. When a shutdown request is received, the Kubelet will initiate shutdown on all pods running on the node with a grace period that depends on the priority of the pod, and then wait for all pods to exit. Each entry in the array represents the graceful shutdown time a pod with a priority class value that lies in the range of that value and the next higher entry in the list when the node is shutting down. For example, to allow critical pods 10s to shutdown, priority>=10000 pods 20s to shutdown, and all remaining pods 30s to shutdown.

shutdownGracePeriodByPodPriority:

  • priority: 2000000000 shutdownGracePeriodSeconds: 10
  • priority: 10000 shutdownGracePeriodSeconds: 20
  • priority: 0 shutdownGracePeriodSeconds: 30

The time the Kubelet will wait before exiting will at most be the maximum of all shutdownGracePeriodSeconds for each priority class range represented on the node. When all pods have exited or reached their grace periods, the Kubelet will release the shutdown inhibit lock. Requires the GracefulNodeShutdown feature gate to be enabled. This configuration must be empty if either ShutdownGracePeriod or ShutdownGracePeriodCriticalPods is set. Default: nil

reservedMemory
[]MemoryReservation

reservedMemory specifies a comma-separated list of memory reservations for NUMA nodes. The parameter makes sense only in the context of the memory manager feature. The memory manager will not allocate reserved memory for container workloads. For example, if you have a NUMA0 with 10Gi of memory and the reservedMemory was specified to reserve 1Gi of memory at NUMA0, the memory manager will assume that only 9Gi is available for allocation. You can specify a different amount of NUMA node and memory types. You can omit this parameter at all, but you should be aware that the amount of reserved memory from all NUMA nodes should be equal to the amount of memory specified by the node allocatable. If at least one node allocatable parameter has a non-zero value, you will need to specify at least one NUMA node. Also, avoid specifying:

  1. Duplicates, the same NUMA node, and memory type, but with a different value.
  2. zero limits for any memory type.
  3. NUMAs nodes IDs that do not exist under the machine.
  4. memory types except for memory and hugepages-

Default: nil

enableProfilingHandler
bool

enableProfilingHandler enables profiling via web interface host:port/debug/pprof/ Default: true

enableDebugFlagsHandler
bool

enableDebugFlagsHandler enables flags endpoint via web interface host:port/debug/flags/v Default: true

seccompDefault
bool

SeccompDefault enables the use of RuntimeDefault as the default seccomp profile for all workloads. This requires the corresponding SeccompDefault feature gate to be enabled as well. Default: false

memoryThrottlingFactor
float64

MemoryThrottlingFactor specifies the factor multiplied by the memory limit or node allocatable memory when setting the cgroupv2 memory.high value to enforce MemoryQoS. Decreasing this factor will set lower high limit for container cgroups and put heavier reclaim pressure while increasing will put less reclaim pressure. See http://kep.k8s.io/2570 for more details. Default: 0.8

registerWithTaints
[]core/v1.Taint

registerWithTaints are an array of taints to add to a node object when the kubelet registers itself. This only takes effect when registerNode is true and upon the initial registration of the node. Default: nil

registerNode
bool

registerNode enables automatic registration with the apiserver. Default: true

SerializedNodeConfigSource

SerializedNodeConfigSource allows us to serialize v1.NodeConfigSource. This type is used internally by the Kubelet for tracking checkpointed dynamic configs. It exists in the kubeletconfig API group because it is classified as a versioned input to the Kubelet.

FieldDescription
apiVersion
string
kubelet.config.k8s.io/v1beta1
kind
string
SerializedNodeConfigSource
source
core/v1.NodeConfigSource

source is the source that we are serializing.

KubeletAnonymousAuthentication

Appears in:

FieldDescription
enabled
bool

enabled allows anonymous requests to the kubelet server. Requests that are not rejected by another authentication method are treated as anonymous requests. Anonymous requests have a username of system:anonymous, and a group name of system:unauthenticated.

KubeletAuthentication

Appears in:

FieldDescription
x509
KubeletX509Authentication

x509 contains settings related to x509 client certificate authentication.

webhook
KubeletWebhookAuthentication

webhook contains settings related to webhook bearer token authentication.

anonymous
KubeletAnonymousAuthentication

anonymous contains settings related to anonymous authentication.

KubeletAuthorization

Appears in:

FieldDescription
mode
KubeletAuthorizationMode

mode is the authorization mode to apply to requests to the kubelet server. Valid values are AlwaysAllow and Webhook. Webhook mode uses the SubjectAccessReview API to determine authorization.

webhook
KubeletWebhookAuthorization

webhook contains settings related to Webhook authorization.

KubeletAuthorizationMode

(Alias of string)

Appears in:

KubeletWebhookAuthentication

Appears in:

FieldDescription
enabled
bool

enabled allows bearer token authentication backed by the tokenreviews.authentication.k8s.io API.

cacheTTL
meta/v1.Duration

cacheTTL enables caching of authentication results

KubeletWebhookAuthorization

Appears in:

FieldDescription
cacheAuthorizedTTL
meta/v1.Duration

cacheAuthorizedTTL is the duration to cache 'authorized' responses from the webhook authorizer.

cacheUnauthorizedTTL
meta/v1.Duration

cacheUnauthorizedTTL is the duration to cache 'unauthorized' responses from the webhook authorizer.

KubeletX509Authentication

Appears in:

FieldDescription
clientCAFile
string

clientCAFile is the path to a PEM-encoded certificate bundle. If set, any request presenting a client certificate signed by one of the authorities in the bundle is authenticated with a username corresponding to the CommonName, and groups corresponding to the Organization in the client certificate.

MemoryReservation

Appears in:

MemoryReservation specifies the memory reservation of different types for each NUMA node

FieldDescription
numaNode [Required]
int32
No description provided.
limits [Required]
core/v1.ResourceList
No description provided.

MemorySwapConfiguration

Appears in:

FieldDescription
swapBehavior
string

swapBehavior configures swap memory available to container workloads. May be one of "", "LimitedSwap": workload combined memory and swap usage cannot exceed pod memory limit "UnlimitedSwap": workloads can use unlimited swap, up to the allocatable limit.

ResourceChangeDetectionStrategy

(Alias of string)

Appears in:

ResourceChangeDetectionStrategy denotes a mode in which internal managers (secret, configmap) are discovering object changes.

ShutdownGracePeriodByPodPriority

Appears in:

ShutdownGracePeriodByPodPriority specifies the shutdown grace period for Pods based on their associated priority class value

FieldDescription
priority [Required]
int32

priority is the priority value associated with the shutdown grace period

shutdownGracePeriodSeconds [Required]
int64

shutdownGracePeriodSeconds is the shutdown grace period in seconds

FormatOptions

Appears in:

FormatOptions contains options for the different logging formats.

FieldDescription
json [Required]
JSONOptions

[Experimental] JSON contains options for logging format "json".

JSONOptions

Appears in:

JSONOptions contains options for logging format "json".

FieldDescription
splitStream [Required]
bool

[Experimental] SplitStream redirects error messages to stderr while info messages go to stdout, with buffering. The default is to write both to stdout, without buffering.

infoBufferSize [Required]
k8s.io/apimachinery/pkg/api/resource.QuantityValue

[Experimental] InfoBufferSize sets the size of the info stream when using split streams. The default is zero, which disables buffering.

LoggingConfiguration

Appears in:

LoggingConfiguration contains logging options Refer Logs Options for more information.

FieldDescription
format [Required]
string

Format Flag specifies the structure of log messages. default value of format is text

flushFrequency [Required]
time.Duration

Maximum number of seconds between log flushes. Ignored if the selected logging backend writes log messages without buffering.

verbosity [Required]
uint32

Verbosity is the threshold that determines which log messages are logged. Default is zero which logs only the most important messages. Higher values enable additional messages. Error messages are always logged.

vmodule [Required]
VModuleConfiguration

VModule overrides the verbosity threshold for individual files. Only supported for "text" log format.

sanitization [Required]
bool

[Experimental] When enabled prevents logging of fields tagged as sensitive (passwords, keys, tokens). Runtime log sanitization may introduce significant computation overhead and therefore should not be enabled in production.`)

options [Required]
FormatOptions

[Experimental] Options holds additional parameters that are specific to the different logging formats. Only the options for the selected format get used, but all of them get validated.

VModuleConfiguration

(Alias of []k8s.io/component-base/config/v1alpha1.VModuleItem)

Appears in:

VModuleConfiguration is a collection of individual file names or patterns and the corresponding verbosity threshold.

Last modified February 18, 2022 at 2:16 PM PST: Update config API reference (5dfea11d6f)