website/content/en/docs/concepts/cluster-administration/cloud-providers.md

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Cloud Providers templates/concept

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AWS

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

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, e.g. 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-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 enable 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

OpenStack

This section describes all the possible configurations which can be used when using OpenStack with Kubernetes. 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 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, in seconds, between sending probes to members of the load balancer.
  • monitor-timeout (Optional): Maximum number of seconds for a monitor to wait for a ping reply before it times out. The value must be less than the delay value.
  • 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.

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.

Router

These configuration options for the OpenStack provider pertain to the kubenet Kubernetes network plugin and should appear in the [Router] 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.

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