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Cloud Providers

This page explains how to manage Kubernetes running on a specific cloud provider.

kubeadm

kubeadm is a popular option for creating kubernetes clusters. kubeadm has configuration options to specify configuration information for cloud providers. For example a typical in-tree cloud provider can be configured using kubeadm as shown below:

apiVersion: kubeadm.k8s.io/v1beta2
kind: InitConfiguration
nodeRegistration:
  kubeletExtraArgs:
    cloud-provider: "openstack"
    cloud-config: "/etc/kubernetes/cloud.conf"
---
apiVersion: kubeadm.k8s.io/v1beta2
kind: ClusterConfiguration
kubernetesVersion: v1.13.0
apiServer:
  extraArgs:
    cloud-provider: "openstack"
    cloud-config: "/etc/kubernetes/cloud.conf"
  extraVolumes:
  - name: cloud
    hostPath: "/etc/kubernetes/cloud.conf"
    mountPath: "/etc/kubernetes/cloud.conf"
controllerManager:
  extraArgs:
    cloud-provider: "openstack"
    cloud-config: "/etc/kubernetes/cloud.conf"
  extraVolumes:
  - name: cloud
    hostPath: "/etc/kubernetes/cloud.conf"
    mountPath: "/etc/kubernetes/cloud.conf"

The in-tree cloud providers typically need both --cloud-provider and --cloud-config specified in the command lines for the kube-apiserver, kube-controller-manager and the kubelet. The contents of the file specified in --cloud-config for each provider is documented below as well.

For all external cloud providers, please follow the instructions on the individual repositories, which are listed under their headings below, or one may view the list of all repositories

AWS

This section describes all the possible configurations which can be used when running Kubernetes on Amazon Web Services.

If you wish to use the external cloud provider, its repository is kubernetes/cloud-provider-aws

Node Name

The AWS cloud provider uses the private DNS name of the AWS instance as the name of the Kubernetes Node object.

Load Balancers

You can setup external load balancers to use specific features in AWS by configuring the annotations as shown below.

apiVersion: v1
kind: Service
metadata:
  name: example
  namespace: kube-system
  labels:
    run: example
  annotations:
     service.beta.kubernetes.io/aws-load-balancer-ssl-cert: arn:aws:acm:xx-xxxx-x:xxxxxxxxx:xxxxxxx/xxxxx-xxxx-xxxx-xxxx-xxxxxxxxx #replace this value
     service.beta.kubernetes.io/aws-load-balancer-backend-protocol: http
spec:
  type: LoadBalancer
  ports:
  - port: 443
    targetPort: 5556
    protocol: TCP
  selector:
    app: example

Different settings can be applied to a load balancer service in AWS using annotations. The following describes the annotations supported on AWS ELBs:

  • service.beta.kubernetes.io/aws-load-balancer-access-log-emit-interval: Used to specify access log emit interval.
  • service.beta.kubernetes.io/aws-load-balancer-access-log-enabled: Used on the service to enable or disable access logs.
  • service.beta.kubernetes.io/aws-load-balancer-access-log-s3-bucket-name: Used to specify access log s3 bucket name.
  • service.beta.kubernetes.io/aws-load-balancer-access-log-s3-bucket-prefix: Used to specify access log s3 bucket prefix.
  • service.beta.kubernetes.io/aws-load-balancer-additional-resource-tags: Used on the service to specify a comma-separated list of key-value pairs which will be recorded as additional tags in the ELB. For example: "Key1=Val1,Key2=Val2,KeyNoVal1=,KeyNoVal2".
  • service.beta.kubernetes.io/aws-load-balancer-backend-protocol: Used on the service to specify the protocol spoken by the backend (pod) behind a listener. If http (default) or https, an HTTPS listener that terminates the connection and parses headers is created. If set to ssl or tcp, a “raw” SSL listener is used. If set to http and aws-load-balancer-ssl-cert is not used then a HTTP listener is used.
  • service.beta.kubernetes.io/aws-load-balancer-ssl-cert: Used on the service to request a secure listener. Value is a valid certificate ARN. For more, see ELB Listener Config CertARN is an IAM or CM certificate ARN, for example arn:aws:acm:us-east-1:123456789012:certificate/12345678-1234-1234-1234-123456789012.
  • service.beta.kubernetes.io/aws-load-balancer-connection-draining-enabled: Used on the service to enable or disable connection draining.
  • service.beta.kubernetes.io/aws-load-balancer-connection-draining-timeout: Used on the service to specify a connection draining timeout.
  • service.beta.kubernetes.io/aws-load-balancer-connection-idle-timeout: Used on the service to specify the idle connection timeout.
  • service.beta.kubernetes.io/aws-load-balancer-cross-zone-load-balancing-enabled: Used on the service to enable or disable cross-zone load balancing.
  • service.beta.kubernetes.io/aws-load-balancer-security-groups: Used to specify the security groups to be added to ELB created. This replaces all other security groups previously assigned to the ELB.
  • service.beta.kubernetes.io/aws-load-balancer-extra-security-groups: Used on the service to specify additional security groups to be added to ELB created
  • service.beta.kubernetes.io/aws-load-balancer-internal: Used on the service to indicate that we want an internal ELB.
  • service.beta.kubernetes.io/aws-load-balancer-proxy-protocol: Used on the service to enable the proxy protocol on an ELB. Right now we only accept the value * which means enabling the proxy protocol on all ELB backends. In the future we could adjust this to allow setting the proxy protocol only on certain backends.
  • service.beta.kubernetes.io/aws-load-balancer-ssl-ports: Used on the service to specify a comma-separated list of ports that will use SSL/HTTPS listeners. Defaults to * (all)

The information for the annotations for AWS is taken from the comments on aws.go

Azure

If you wish to use the external cloud provider, its repository is kubernetes/cloud-provider-azure

Node Name

The Azure cloud provider uses the hostname of the node (as determined by the kubelet or overridden with --hostname-override) as the name of the Kubernetes Node object. Note that the Kubernetes Node name must match the Azure VM name.

CloudStack

If you wish to use the external cloud provider, its repository is apache/cloudstack-kubernetes-provider

Node Name

The CloudStack cloud provider uses the hostname of the node (as determined by the kubelet or overridden with --hostname-override) as the name of the Kubernetes Node object. Note that the Kubernetes Node name must match the CloudStack VM name.

GCE

If you wish to use the external cloud provider, its repository is kubernetes/cloud-provider-gcp

Node Name

The GCE cloud provider uses the hostname of the node (as determined by the kubelet or overridden with --hostname-override) as the name of the Kubernetes Node object. Note that the first segment of the Kubernetes Node name must match the GCE instance name (e.g. a Node named kubernetes-node-2.c.my-proj.internal must correspond to an instance named kubernetes-node-2).

OpenStack

This section describes all the possible configurations which can be used when using OpenStack with Kubernetes.

If you wish to use the external cloud provider, its repository is kubernetes/cloud-provider-openstack

Node Name

The OpenStack cloud provider uses the instance name (as determined from OpenStack metadata) as the name of the Kubernetes Node object. Note that the instance name must be a valid Kubernetes Node name in order for the kubelet to successfully register its Node object.

Services

The OpenStack cloud provider implementation for Kubernetes supports the use of these OpenStack services from the underlying cloud, where available:

Service API Version(s) Required
Block Storage (Cinder) V1†, V2, V3 No
Compute (Nova) V2 No
Identity (Keystone) V2‡, V3 Yes
Load Balancing (Neutron) V1§, V2 No
Load Balancing (Octavia) V2 No

† Block Storage V1 API support is deprecated, Block Storage V3 API support was added in Kubernetes 1.9.

‡ Identity V2 API support is deprecated and will be removed from the provider in a future release. As of the “Queens” release, OpenStack will no longer expose the Identity V2 API.

§ Load Balancing V1 API support was removed in Kubernetes 1.9.

Service discovery is achieved by listing the service catalog managed by OpenStack Identity (Keystone) using the auth-url provided in the provider configuration. The provider will gracefully degrade in functionality when OpenStack services other than Keystone are not available and simply disclaim support for impacted features. Certain features are also enabled or disabled based on the list of extensions published by Neutron in the underlying cloud.

cloud.conf

Kubernetes knows how to interact with OpenStack via the file cloud.conf. It is the file that will provide Kubernetes with credentials and location for the OpenStack auth endpoint. You can create a cloud.conf file by specifying the following details in it

Typical configuration

This is an example of a typical configuration that touches the values that most often need to be set. It points the provider at the OpenStack cloud’s Keystone endpoint, provides details for how to authenticate with it, and configures the load balancer:

[Global]
username=user
password=pass
auth-url=https://<keystone_ip>/identity/v3
tenant-id=c869168a828847f39f7f06edd7305637
domain-id=2a73b8f597c04551a0fdc8e95544be8a

[LoadBalancer]
subnet-id=6937f8fa-858d-4bc9-a3a5-18d2c957166a
Global

These configuration options for the OpenStack provider pertain to its global configuration and should appear in the [Global] section of the cloud.conf file:

  • auth-url (Required): The URL of the keystone API used to authenticate. On OpenStack control panels, this can be found at Access and Security > API Access > Credentials.
  • username (Required): Refers to the username of a valid user set in keystone.
  • password (Required): Refers to the password of a valid user set in keystone.
  • tenant-id (Required): Used to specify the id of the project where you want to create your resources.
  • tenant-name (Optional): Used to specify the name of the project where you want to create your resources.
  • trust-id (Optional): Used to specify the identifier of the trust to use for authorization. A trust represents a user’s (the trustor) authorization to delegate roles to another user (the trustee), and optionally allow the trustee to impersonate the trustor. Available trusts are found under the /v3/OS-TRUST/trusts endpoint of the Keystone API.
  • domain-id (Optional): Used to specify the id of the domain your user belongs to.
  • domain-name (Optional): Used to specify the name of the domain your user belongs to.
  • region (Optional): Used to specify the identifier of the region to use when running on a multi-region OpenStack cloud. A region is a general division of an OpenStack deployment. Although a region does not have a strict geographical connotation, a deployment can use a geographical name for a region identifier such as us-east. Available regions are found under the /v3/regions endpoint of the Keystone API.
  • ca-file (Optional): Used to specify the path to your custom CA file.

When using Keystone V3 - which changes tenant to project - the tenant-id value is automatically mapped to the project construct in the API.

Load Balancer

These configuration options for the OpenStack provider pertain to the load balancer and should appear in the [LoadBalancer] section of the cloud.conf file:

  • lb-version (Optional): Used to override automatic version detection. Valid values are v1 or v2. Where no value is provided automatic detection will select the highest supported version exposed by the underlying OpenStack cloud.
  • use-octavia (Optional): Used to determine whether to look for and use an Octavia LBaaS V2 service catalog endpoint. Valid values are true or false. Where true is specified and an Octaiva LBaaS V2 entry can not be found, the provider will fall back and attempt to find a Neutron LBaaS V2 endpoint instead. The default value is false.
  • subnet-id (Optional): Used to specify the id of the subnet you want to create your loadbalancer on. Can be found at Network > Networks. Click on the respective network to get its subnets.
  • floating-network-id (Optional): If specified, will create a floating IP for the load balancer.
  • lb-method (Optional): Used to specify an algorithm by which load will be distributed amongst members of the load balancer pool. The value can be ROUND_ROBIN, LEAST_CONNECTIONS, or SOURCE_IP. The default behavior if none is specified is ROUND_ROBIN.
  • lb-provider (Optional): Used to specify the provider of the load balancer. If not specified, the default provider service configured in neutron will be used.
  • create-monitor (Optional): Indicates whether or not to create a health monitor for the Neutron load balancer. Valid values are true and false. The default is false. When true is specified then monitor-delay, monitor-timeout, and monitor-max-retries must also be set.
  • monitor-delay (Optional): The time between sending probes to members of the load balancer. Ensure that you specify a valid time unit. The valid time units are “ns”, “us” (or “µs”), “ms”, “s”, “m”, “h”
  • monitor-timeout (Optional): Maximum time for a monitor to wait for a ping reply before it times out. The value must be less than the delay value. Ensure that you specify a valid time unit. The valid time units are “ns”, “us” (or “µs”), “ms”, “s”, “m”, “h”
  • monitor-max-retries (Optional): Number of permissible ping failures before changing the load balancer member’s status to INACTIVE. Must be a number between 1 and 10.
  • manage-security-groups (Optional): Determines whether or not the load balancer should automatically manage the security group rules. Valid values are true and false. The default is false. When true is specified node-security-group must also be supplied.
  • node-security-group (Optional): ID of the security group to manage.
Block Storage

These configuration options for the OpenStack provider pertain to block storage and should appear in the [BlockStorage] section of the cloud.conf file:

  • bs-version (Optional): Used to override automatic version detection. Valid values are v1, v2, v3 and auto. When auto is specified automatic detection will select the highest supported version exposed by the underlying OpenStack cloud. The default value if none is provided is auto.
  • trust-device-path (Optional): In most scenarios the block device names provided by Cinder (e.g. /dev/vda) can not be trusted. This boolean toggles this behavior. Setting it to true results in trusting the block device names provided by Cinder. The default value of false results in the discovery of the device path based on its serial number and /dev/disk/by-id mapping and is the recommended approach.
  • ignore-volume-az (Optional): Used to influence availability zone use when attaching Cinder volumes. When Nova and Cinder have different availability zones, this should be set to true. This is most commonly the case where there are many Nova availability zones but only one Cinder availability zone. The default value is false to preserve the behavior used in earlier releases, but may change in the future.
  • node-volume-attach-limit (Optional): Maximum number of Volumes that can be attached to the node, default is 256 for cinder.

If deploying Kubernetes versions <= 1.8 on an OpenStack deployment that uses paths rather than ports to differentiate between endpoints it may be necessary to explicitly set the bs-version parameter. A path based endpoint is of the form http://foo.bar/volume while a port based endpoint is of the form http://foo.bar:xxx.

In environments that use path based endpoints and Kubernetes is using the older auto-detection logic a BS API version autodetection failed. error will be returned on attempting volume detachment. To workaround this issue it is possible to force the use of Cinder API version 2 by adding this to the cloud provider configuration:

[BlockStorage]
bs-version=v2
Metadata

These configuration options for the OpenStack provider pertain to metadata and should appear in the [Metadata] section of the cloud.conf file:

  • search-order (Optional): This configuration key influences the way that the provider retrieves metadata relating to the instance(s) in which it runs. The default value of configDrive,metadataService results in the provider retrieving metadata relating to the instance from the config drive first if available and then the metadata service. Alternative values are:
    • configDrive - Only retrieve instance metadata from the configuration drive.
    • metadataService - Only retrieve instance metadata from the metadata service.
    • metadataService,configDrive - Retrieve instance metadata from the metadata service first if available, then the configuration drive.

Influencing this behavior may be desirable as the metadata on the configuration drive may grow stale over time, whereas the metadata service always provides the most up to date view. Not all OpenStack clouds provide both configuration drive and metadata service though and only one or the other may be available which is why the default is to check both.

Route

These configuration options for the OpenStack provider pertain to the kubenet Kubernetes network plugin and should appear in the [Route] section of the cloud.conf file:

  • router-id (Optional): If the underlying cloud’s Neutron deployment supports the extraroutes extension then use router-id to specify a router to add routes to. The router chosen must span the private networks containing your cluster nodes (typically there is only one node network, and this value should be the default router for the node network). This value is required to use kubenet on OpenStack.

OVirt

Node Name

The OVirt cloud provider uses the hostname of the node (as determined by the kubelet or overridden with --hostname-override) as the name of the Kubernetes Node object. Note that the Kubernetes Node name must match the VM FQDN (reported by OVirt under <vm><guest_info><fqdn>...</fqdn></guest_info></vm>)

Photon

Node Name

The Photon cloud provider uses the hostname of the node (as determined by the kubelet or overridden with --hostname-override) as the name of the Kubernetes Node object. Note that the Kubernetes Node name must match the Photon VM name (or if overrideIP is set to true in the --cloud-config, the Kubernetes Node name must match the Photon VM IP address).

vSphere

For all vSphere deployments on vSphere >= 6.7U3, the external vSphere cloud provider, along with the vSphere CSI driver is recommended. See Deploying a Kubernetes Cluster on vSphere with CSI and CPI for a quick start guide.

If you are running vSphere < 6.7U3, the in-tree vSphere cloud provider is recommended. See Running a Kubernetes Cluster on vSphere with kubeadm for a quick start guide.

For in-depth documentation on the vSphere cloud provider, visit the vSphere cloud provider docs site.

IBM Cloud Kubernetes Service

Compute nodes

By using the IBM Cloud Kubernetes Service provider, you can create clusters with a mixture of virtual and physical (bare metal) nodes in a single zone or across multiple zones in a region. For more information, see Planning your cluster and worker node setup.

The name of the Kubernetes Node object is the private IP address of the IBM Cloud Kubernetes Service worker node instance.

Networking

The IBM Cloud Kubernetes Service provider provides VLANs for quality network performance and network isolation for nodes. You can set up custom firewalls and Calico network policies to add an extra layer of security for your cluster, or connect your cluster to your on-prem data center via VPN. For more information, see Planning in-cluster and private networking.

To expose apps to the public or within the cluster, you can leverage NodePort, LoadBalancer, or Ingress services. You can also customize the Ingress application load balancer with annotations. For more information, see Planning to expose your apps with external networking.

Storage

The IBM Cloud Kubernetes Service provider leverages Kubernetes-native persistent volumes to enable users to mount file, block, and cloud object storage to their apps. You can also use database-as-a-service and third-party add-ons for persistent storage of your data. For more information, see Planning highly available persistent storage.

Baidu Cloud Container Engine

Node Name

The Baidu cloud provider uses the private IP address of the node (as determined by the kubelet or overridden with --hostname-override) as the name of the Kubernetes Node object. Note that the Kubernetes Node name must match the Baidu VM private IP.

Tencent Kubernetes Engine

If you wish to use the external cloud provider, its repository is TencentCloud/tencentcloud-cloud-controller-manager.

Node Name

The Tencent cloud provider uses the hostname of the node (as determined by the kubelet or overridden with --hostname-override) as the name of the Kubernetes Node object. Note that the Kubernetes Node name must match the Tencent VM private IP.

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