Assign static public IPs to Kubernetes nodes (GKE, EKS)
Welcome to KubeIP v2, a complete overhaul of the popular DoiT KubeIP v1-main open-source project, originally developed by Aviv Laufer.
KubeIP v2 expands its support beyond Google Cloud (as in v1) to include AWS, and it’s designed to be extendable to other cloud providers that allow assigning static public IP to VMs. We’ve also transitioned from a Kubernetes controller to a standard DaemonSet, enhancing reliability and ease of use.
KubeIP v1 is still available in the v1-main branch. No further development is planned. We will fix critical bugs and security issues, but we will not add new features.
Kubernetes’ nodes don’t necessarily need their own public IP addresses to communicate. However, there are certain situations where it’s beneficial for nodes in a node pool to have their own unique public IP addresses.
For instance, in gaming applications, a console might need to establish a direct connection with a cloud virtual machine to reduce the number of hops.
Similarly, if you have multiple agents running on Kubernetes that need a direct server connection, and the server needs to whitelist all agent IPs, having dedicated public IPs can be useful. These scenarios, among others, can be handled on a cloud-managed Kubernetes cluster using Node Public IP.
KubeIP is a utility that assigns a static public IP to each node it manages. The IP is allocated to the node’s primary network interface, chosen from a pool of reserved static IPs using platform-supported filtering and ordering.
If there are no static public IPs left, KubeIP will hold on until one becomes available. When a node is removed, KubeIP releases the static public IP back into the pool of reserved static IPs.
Deploy KubeIP as a DaemonSet on your desired nodes using standard Kubernetes mechanism. Once deployed, KubeIP will assign a static public IP to each node it operates on. If no static public IP is available, KubeIP will wait until one becomes available. When a node is deleted, KubeIP will release the static public IP and reassign ephemeral public IP to the node.
KubeIP supports dual-stack IPv4/IPv6 GKE clusters and Google Cloud static public IPv6 addresses.
To enable IPv6 support, set the ipv6
flag (or set IPV6
environment variable) to true
(default is false
).
KubeIP requires a Kubernetes service account with at least the following permissions:
apiVersion: v1
kind: ServiceAccount
metadata:
name: kubeip-service-account
namespace: kube-system
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
name: kubeip-cluster-role
rules:
- apiGroups: [ "" ]
resources: [ "nodes" ]
verbs: [ "get" ]
- apiGroups: [ "coordination.k8s.io" ]
resources: [ "leases" ]
verbs: [ "create", "get", "delete" ]
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
name: kubeip-cluster-role-binding
subjects:
- kind: ServiceAccount
name: kubeip-service-account
namespace: kube-system
roleRef:
kind: ClusterRole
name: kubeip-cluster-role
apiGroup: rbac.authorization.k8s.io
Deploy KubeIP as a DaemonSet on your desired nodes using standard Kubernetes selectors. Once deployed, KubeIP will assign a static public IP to the node’s primary network interface, selected from a list of reserved static IPs using platform-supported filtering. If no static public IP is available, KubeIP will wait until one becomes available. When a node is deleted, KubeIP will release the static public IP.
apiVersion: apps/v1
kind: DaemonSet
metadata:
name: kubeip
spec:
selector:
matchLabels:
app: kubeip
template:
metadata:
labels:
app: kubeip
spec:
serviceAccountName: kubeip-service-account
terminationGracePeriodSeconds: 30
priorityClassName: system-node-critical
nodeSelector:
kubeip.com/public: "true"
containers:
- name: kubeip
image: doitintl/kubeip-agent
resources:
requests:
cpu: 100m
env:
- name: NODE_NAME
valueFrom:
fieldRef:
fieldPath: spec.nodeName
- name: FILTER
value: PUT_PLATFORM_SPECIFIC_FILTER_HERE
- name: LOG_LEVEL
value: debug
- name: LOG_JSON
value: "true"
KubeIP can be configured to attempt removal of a Taint Key from its node once the static IP has been successfully assigned, preventing workloads from being scheduled on the node until it has successfully received a static IP address. This can be useful, for example, in cases where the workload must call resources with IP-whitelisting, to prevent race conditions between KubeIP and the workload on newly provisioned nodes.
To enable this feature, set the taint-key
configuration parameter (See How to run KubeIP) to the taint key that
should be removed. Then add a toleration to the KubeIP DaemonSet, so that it itself can be scheduled on the tainted nodes. For example,
given that new nodes are created with a taint key of kubeip.com/not-ready
:
kind: DaemonSet
spec:
template:
spec:
serviceAccountName: kubeip-service-account
tolerations:
- key: kubeip.com/not-ready
operator: Exists
effect: NoSchedule
securityContext:
runAsNonRoot: true
runAsUser: 1001
runAsGroup: 1001
fsGroup: 1001
containers:
- name: kubeip
image: doitintl/kubeip-agent
env:
- name: TAINT_KEY
value: kubeip.com/not-ready
securityContext:
privileged: false
allowPrivilegeEscalation: false
capabilities:
drop:
- ALL
readOnlyRootFilesystem: true
The parameter has no default value, and if not set, KubeIP will not attempt to remove any taints. If the provided Taint Key is not present on the node, KubeIP will simply log this fact and continue normally without attempting to remove it. If the Taint Key is present, but removing it fails for some reason, KubeIP will release the IP address back into the pool before restarting and trying again.
Using this feature requires KubeIP to have permission to patch nodes. To use this feature, the ClusterRole
resource rules need to be
updated. Note that if this configuration option is not set, KubeIP will not attempt to patch any nodes, and the change to the rules is not
necessary.
Please keep in mind that this will give KubeIP permission to make updates to any node in your cluster, so please make sure that this aligns with your security requirements before enabling this feature!
rules:
- apiGroups: [ "" ]
resources: [ "nodes" ]
verbs: [ "get", "patch" ]
Make sure that KubeIP DaemonSet is deployed on nodes that have a public IP (node running in public subnet) and uses a Kubernetes service account bound to the IAM role with the following permissions:
Version: '2012-10-17'
Statement:
- Effect: Allow
Action:
- ec2:AssociateAddress
- ec2:DisassociateAddress
- ec2:DescribeInstances
- ec2:DescribeAddresses
Resource: '*'
KubeIP supports filtering of reserved Elastic IPs using tags and Elastic IP properties. To use this feature, add the filter
flag (or
set FILTER
environment variable) to the KubeIP DaemonSet:
- name: FILTER
value: "Name=tag:env,Values=dev;Name=tag:app,Values=streamer"
KubeIP AWS filter supports the same filter syntax as the AWS describe-addresses
command. For more information,
see describe-addresses. If you specify multiple
filters, they are joined with an AND
, and the request returns only results that match all the specified filters. Multiple filters must be
separated by semicolons (;
).
Ensure that the KubeIP DaemonSet is deployed on nodes with a public IP (nodes in a public subnet) and uses a Kubernetes service account bound to an IAM role with the following permissions:
title: "KubeIP Role"
description: "KubeIP required permissions"
stage: "GA"
includedPermissions:
- compute.instances.addAccessConfig
- compute.instances.deleteAccessConfig
- compute.instances.get
- compute.addresses.get
- compute.addresses.list
- compute.addresses.use
- compute.zoneOperations.get
- compute.subnetworks.useExternalIp
- compute.projects.get
KubeIP Google Cloud filter supports the same filter syntax as the Google Cloud gcloud compute addresses list
command. For more
information, see gcloud topic filter. If you specify multiple filters, they
are joined with an AND
, and the request returns only results that match all the specified filters. Multiple filters must be separated by
semicolons (;
).
To use this feature, add the filter
flag (or set FILTER
environment variable) to the KubeIP DaemonSet:
- name: FILTER
value: "labels.env=dev;labels.app=streamer"
KubeIP is an open-source project, and we welcome your contributions!
KubeIP is written in Go and can be built using standard Go tools. To build KubeIP, run the following command:
make build
KubeIP is a standard command-line application. To explore the available options, run the following command:
kubeip-agent run --help
NAME:
kubeip-agent run - run agent
USAGE:
kubeip-agent run [command options] [arguments...]
OPTIONS:
Configuration
--filter value [ --filter value ] filter for the IP addresses [$FILTER]
--ipv6 enable IPv6 support (default: false) [$IPV6]
--kubeconfig value path to Kubernetes configuration file (not needed if running in node) [$KUBECONFIG]
--node-name value Kubernetes node name (not needed if running in node) [$NODE_NAME]
--order-by value order by for the IP addresses [$ORDER_BY]
--project value name of the GCP project or the AWS account ID (not needed if running in node) [$PROJECT]
--region value name of the GCP region or the AWS region (not needed if running in node) [$REGION]
--release-on-exit release the static public IP address on exit (default: true) [$RELEASE_ON_EXIT]
--taint-key value specify a taint key to remove from the node once the static public IP address is assigned [$TAINT_KEY]
--retry-attempts value number of attempts to assign the static public IP address (default: 10) [$RETRY_ATTEMPTS]
--retry-interval value when the agent fails to assign the static public IP address, it will retry after this interval (default: 5m0s) [$RETRY_INTERVAL]
--lease-duration value duration of the kubernetes lease (default: 5) [$LEASE_DURATION]
--lease-namespace value namespace of the kubernetes lease (default: "default") [$LEASE_NAMESPACE]
Development
--develop-mode enable develop mode (default: false) [$DEV_MODE]
Logging
--json produce log in JSON format: Logstash and Splunk friendly (default: false) [$LOG_JSON]
--log-level value set log level (debug, info(*), warning, error, fatal, panic) (default: "info") [$LOG_LEVEL]
To test KubeIP, create a pool of reserved static public IPs, ensuring that the pool has enough IPs to assign to all nodes that KubeIP will operate on. Use labels to filter the pool of reserved static public IPs.
Next, create a Kubernetes cluster and deploy KubeIP as a DaemonSet on your desired nodes. Ensure that the nodes have a public IP (nodes in a public subnet). Configure KubeIP to use the pool of reserved static public IPs, using filters and order by.
Finally, scale the number of nodes in the cluster and verify that KubeIP assigns a static public IP to each node. Scale down the number of nodes in the cluster and verify that KubeIP releases the static public IP addresses.
The examples/aws folder contains a Terraform configuration that creates an EKS cluster and deploys KubeIP as a DaemonSet on the cluster nodes in a public subnet. The Terraform configuration also creates a pool of reserved Elastic IPs and configures KubeIP to use the pool of reserved static public IPs.
To run the example, follow these steps:
cd examples/aws
terraform init
terraform apply
The examples/gcp folder contains a Terraform configuration that creates a GKE cluster and deploys KubeIP as a DaemonSet on the cluster nodes in a public subnet. The Terraform configuration also creates a pool of reserved static public IPs and configures KubeIP to use the pool of reserved static public IPs.
To run the example, follow these steps:
cd examples/gcp
terraform init
terraform apply -var="project_id=<your-project-id>"
To run the example with GKE dual-stack IPv4/IPv6 cluster, follow these steps:
cd examples/gcp
terraform init
terraform apply -var="project_id=<your-project-id>" -var="ipv6_support=true"