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The Kubernetes network proxy runs on each node. This reflects services as defined in the Kubernetes API on each node and can do simple TCP, UDP, and SCTP stream forwarding or round robin TCP, UDP, and SCTP forwarding across a set of backends. Service cluster IPs and ports are currently found through Docker-links-compatible environment variables specifying ports opened by the service proxy. There is an optional addon that provides cluster DNS for these cluster IPs. The user must create a service with the apiserver API to configure the proxy.

kube-proxy [flags]


--azure-container-registry-config string

Path to the file containing Azure container registry configuration information.

--bind-address string     Default:

The IP address for the proxy server to serve on (set to '' for all IPv4 interfaces and '::' for all IPv6 interfaces)


If true kube-proxy will treat failure to bind to a port as fatal and exit


If true cleanup iptables and ipvs rules and exit.

--cluster-cidr string

The CIDR range of pods in the cluster. When configured, traffic sent to a Service cluster IP from outside this range will be masqueraded and traffic sent from pods to an external LoadBalancer IP will be directed to the respective cluster IP instead

--config string

The path to the configuration file.

--config-sync-period duration     Default: 15m0s

How often configuration from the apiserver is refreshed. Must be greater than 0.

--conntrack-max-per-core int32     Default: 32768

Maximum number of NAT connections to track per CPU core (0 to leave the limit as-is and ignore conntrack-min).

--conntrack-min int32     Default: 131072

Minimum number of conntrack entries to allocate, regardless of conntrack-max-per-core (set conntrack-max-per-core=0 to leave the limit as-is).

--conntrack-tcp-timeout-close-wait duration     Default: 1h0m0s

NAT timeout for TCP connections in the CLOSE_WAIT state

--conntrack-tcp-timeout-established duration     Default: 24h0m0s

Idle timeout for established TCP connections (0 to leave as-is)

--detect-local-mode LocalMode

Mode to use to detect local traffic

--feature-gates <comma-separated 'key=True|False' pairs>

A set of key=value pairs that describe feature gates for alpha/experimental features. Options are:
APIListChunking=true|false (BETA - default=true)
APIPriorityAndFairness=true|false (BETA - default=true)
APIResponseCompression=true|false (BETA - default=true)
APIServerIdentity=true|false (ALPHA - default=false)
AllAlpha=true|false (ALPHA - default=false)
AllBeta=true|false (BETA - default=false)
AllowInsecureBackendProxy=true|false (BETA - default=true)
AnyVolumeDataSource=true|false (ALPHA - default=false)
AppArmor=true|false (BETA - default=true)
BalanceAttachedNodeVolumes=true|false (ALPHA - default=false)
BoundServiceAccountTokenVolume=true|false (ALPHA - default=false)
CPUManager=true|false (BETA - default=true)
CRIContainerLogRotation=true|false (BETA - default=true)
CSIInlineVolume=true|false (BETA - default=true)
CSIMigration=true|false (BETA - default=true)
CSIMigrationAWS=true|false (BETA - default=false)
CSIMigrationAWSComplete=true|false (ALPHA - default=false)
CSIMigrationAzureDisk=true|false (BETA - default=false)
CSIMigrationAzureDiskComplete=true|false (ALPHA - default=false)
CSIMigrationAzureFile=true|false (ALPHA - default=false)
CSIMigrationAzureFileComplete=true|false (ALPHA - default=false)
CSIMigrationGCE=true|false (BETA - default=false)
CSIMigrationGCEComplete=true|false (ALPHA - default=false)
CSIMigrationOpenStack=true|false (BETA - default=false)
CSIMigrationOpenStackComplete=true|false (ALPHA - default=false)
CSIMigrationvSphere=true|false (BETA - default=false)
CSIMigrationvSphereComplete=true|false (BETA - default=false)
CSIServiceAccountToken=true|false (ALPHA - default=false)
CSIStorageCapacity=true|false (ALPHA - default=false)
CSIVolumeFSGroupPolicy=true|false (BETA - default=true)
ConfigurableFSGroupPolicy=true|false (BETA - default=true)
CronJobControllerV2=true|false (ALPHA - default=false)
CustomCPUCFSQuotaPeriod=true|false (ALPHA - default=false)
DefaultPodTopologySpread=true|false (BETA - default=true)
DevicePlugins=true|false (BETA - default=true)
DisableAcceleratorUsageMetrics=true|false (BETA - default=true)
DownwardAPIHugePages=true|false (ALPHA - default=false)
DynamicKubeletConfig=true|false (BETA - default=true)
EfficientWatchResumption=true|false (ALPHA - default=false)
EndpointSlice=true|false (BETA - default=true)
EndpointSliceNodeName=true|false (ALPHA - default=false)
EndpointSliceProxying=true|false (BETA - default=true)
EndpointSliceTerminatingCondition=true|false (ALPHA - default=false)
EphemeralContainers=true|false (ALPHA - default=false)
ExpandCSIVolumes=true|false (BETA - default=true)
ExpandInUsePersistentVolumes=true|false (BETA - default=true)
ExpandPersistentVolumes=true|false (BETA - default=true)
ExperimentalHostUserNamespaceDefaulting=true|false (BETA - default=false)
GenericEphemeralVolume=true|false (ALPHA - default=false)
GracefulNodeShutdown=true|false (ALPHA - default=false)
HPAContainerMetrics=true|false (ALPHA - default=false)
HPAScaleToZero=true|false (ALPHA - default=false)
HugePageStorageMediumSize=true|false (BETA - default=true)
IPv6DualStack=true|false (ALPHA - default=false)
ImmutableEphemeralVolumes=true|false (BETA - default=true)
KubeletCredentialProviders=true|false (ALPHA - default=false)
KubeletPodResources=true|false (BETA - default=true)
LegacyNodeRoleBehavior=true|false (BETA - default=true)
LocalStorageCapacityIsolation=true|false (BETA - default=true)
LocalStorageCapacityIsolationFSQuotaMonitoring=true|false (ALPHA - default=false)
MixedProtocolLBService=true|false (ALPHA - default=false)
NodeDisruptionExclusion=true|false (BETA - default=true)
NonPreemptingPriority=true|false (BETA - default=true)
PodDisruptionBudget=true|false (BETA - default=true)
PodOverhead=true|false (BETA - default=true)
ProcMountType=true|false (ALPHA - default=false)
QOSReserved=true|false (ALPHA - default=false)
RemainingItemCount=true|false (BETA - default=true)
RemoveSelfLink=true|false (BETA - default=true)
RootCAConfigMap=true|false (BETA - default=true)
RotateKubeletServerCertificate=true|false (BETA - default=true)
RunAsGroup=true|false (BETA - default=true)
ServerSideApply=true|false (BETA - default=true)
ServiceAccountIssuerDiscovery=true|false (BETA - default=true)
ServiceLBNodePortControl=true|false (ALPHA - default=false)
ServiceNodeExclusion=true|false (BETA - default=true)
ServiceTopology=true|false (ALPHA - default=false)
SetHostnameAsFQDN=true|false (BETA - default=true)
SizeMemoryBackedVolumes=true|false (ALPHA - default=false)
StorageVersionAPI=true|false (ALPHA - default=false)
StorageVersionHash=true|false (BETA - default=true)
Sysctls=true|false (BETA - default=true)
TTLAfterFinished=true|false (ALPHA - default=false)
TopologyManager=true|false (BETA - default=true)
ValidateProxyRedirects=true|false (BETA - default=true)
WarningHeaders=true|false (BETA - default=true)
WinDSR=true|false (ALPHA - default=false)
WinOverlay=true|false (BETA - default=true)
WindowsEndpointSliceProxying=true|false (ALPHA - default=false)

--healthz-bind-address ipport     Default:

The IP address with port for the health check server to serve on (set to '' for all IPv4 interfaces and '[::]:10256' for all IPv6 interfaces). Set empty to disable.

-h, --help

help for kube-proxy

--hostname-override string

If non-empty, will use this string as identification instead of the actual hostname.

--iptables-masquerade-bit int32     Default: 14

If using the pure iptables proxy, the bit of the fwmark space to mark packets requiring SNAT with. Must be within the range [0, 31].

--iptables-min-sync-period duration     Default: 1s

The minimum interval of how often the iptables rules can be refreshed as endpoints and services change (e.g. '5s', '1m', '2h22m').

--iptables-sync-period duration     Default: 30s

The maximum interval of how often iptables rules are refreshed (e.g. '5s', '1m', '2h22m'). Must be greater than 0.

--ipvs-exclude-cidrs strings

A comma-separated list of CIDR's which the ipvs proxier should not touch when cleaning up IPVS rules.

--ipvs-min-sync-period duration

The minimum interval of how often the ipvs rules can be refreshed as endpoints and services change (e.g. '5s', '1m', '2h22m').

--ipvs-scheduler string

The ipvs scheduler type when proxy mode is ipvs


Enable strict ARP by setting arp_ignore to 1 and arp_announce to 2

--ipvs-sync-period duration     Default: 30s

The maximum interval of how often ipvs rules are refreshed (e.g. '5s', '1m', '2h22m'). Must be greater than 0.

--ipvs-tcp-timeout duration

The timeout for idle IPVS TCP connections, 0 to leave as-is. (e.g. '5s', '1m', '2h22m').

--ipvs-tcpfin-timeout duration

The timeout for IPVS TCP connections after receiving a FIN packet, 0 to leave as-is. (e.g. '5s', '1m', '2h22m').

--ipvs-udp-timeout duration

The timeout for IPVS UDP packets, 0 to leave as-is. (e.g. '5s', '1m', '2h22m').

--kube-api-burst int32     Default: 10

Burst to use while talking with kubernetes apiserver

--kube-api-content-type string     Default: "application/vnd.kubernetes.protobuf"

Content type of requests sent to apiserver.

--kube-api-qps float     Default: 5

QPS to use while talking with kubernetes apiserver

--kubeconfig string

Path to kubeconfig file with authorization information (the master location can be overridden by the master flag).

--log-flush-frequency duration     Default: 5s

Maximum number of seconds between log flushes


If using the pure iptables proxy, SNAT all traffic sent via Service cluster IPs (this not commonly needed)

--master string

The address of the Kubernetes API server (overrides any value in kubeconfig)

--metrics-bind-address ipport     Default:

The IP address with port for the metrics server to serve on (set to '' for all IPv4 interfaces and '[::]:10249' for all IPv6 interfaces). Set empty to disable.

--nodeport-addresses strings

A string slice of values which specify the addresses to use for NodePorts. Values may be valid IP blocks (e.g., The default empty string slice ([]) means to use all local addresses.

--oom-score-adj int32     Default: -999

The oom-score-adj value for kube-proxy process. Values must be within the range [-1000, 1000]


If true enables profiling via web interface on /debug/pprof handler.

--proxy-mode ProxyMode

Which proxy mode to use: 'userspace' (older) or 'iptables' (faster) or 'ipvs' or 'kernelspace' (windows). If blank, use the best-available proxy (currently iptables). If the iptables proxy is selected, regardless of how, but the system's kernel or iptables versions are insufficient, this always falls back to the userspace proxy.

--proxy-port-range port-range

Range of host ports (beginPort-endPort, single port or beginPort+offset, inclusive) that may be consumed in order to proxy service traffic. If (unspecified, 0, or 0-0) then ports will be randomly chosen.

--show-hidden-metrics-for-version string

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 ., 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.

--udp-timeout duration     Default: 250ms

How long an idle UDP connection will be kept open (e.g. '250ms', '2s'). Must be greater than 0. Only applicable for proxy-mode=userspace

--version version[=true]

Print version information and quit

--write-config-to string

If set, write the default configuration values to this file and exit.

Last modified March 10, 2021 at 10:26 AM PST: Update data type presentation in component reference (fa183e46a6)