[Global] Zone = us-east-1c (1)
OpenShift Container Platform can be configured to access an AWS EC2 infrastructure, including using AWS volumes as persistent storage for application data. After AWS is configured properly, some additional configurations will need to be completed on the OpenShift Container Platform hosts.
Configuring AWS for OpenShift Container Platform requires the following permissions:
Elastic Compute Cloud(EC2) |
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Elastic Load Balancing |
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Elastic Compute Cloud(EC2) |
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When installing OpenShift Container Platform on AWS, ensure that you set up the appropriate security groups.
These are some ports that you must have in your security groups, without which the installation fails. You may need more depending on the cluster configuration you want to install. For more information and to adjust your security groups accordingly, see Required Ports for more information.
All OpenShift Container Platform Hosts |
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etcd Security Group |
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Master Security Group |
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Node Security Group |
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Infrastructure Nodes (ones that can host the OpenShift Container Platform router) |
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If configuring external load-balancers (ELBs) for load balancing the masters and/or routers, you also need to configure Ingress and Egress security groups for the ELBs appropriately.
In AWS, situations that require overriding the variables include:
| Variable | Usage |
|---|---|
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The user is installing in a VPC that is not configured for both |
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You have multiple network interfaces configured and want to
use one other than the default. You must also set the
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If |
For EC2 hosts in particular, they must be deployed in a VPC that has both
DNS host names and DNS resolution enabled, and openshift_hostname
should not be overridden.
To set the required AWS variables, create a /etc/origin/cloudprovider/aws.conf file with the following contents on all of your OpenShift Container Platform hosts, both masters and nodes:
[Global] Zone = us-east-1c (1)
| 1 | This is the Availability Zone of your AWS Instance and where your EBS Volume resides; this information is obtained from the AWS Managment Console. |
You can set the AWS configuration on your OpenShift Container Platform master hosts in two ways:
During
advanced installations,
AWS can be configured using
the openshift_cloudprovider_aws_access_key, openshift_cloudprovider_aws_secret_key, openshift_cloudprovider_kind, openshift_clusterid parameters, which are configurable in the inventory file.
# Cloud Provider Configuration
#
# Note: You may make use of environment variables rather than store
# sensitive configuration within the ansible inventory.
# For example:
#openshift_cloudprovider_aws_access_key="{{ lookup('env','AWS_ACCESS_KEY_ID') }}"
#openshift_cloudprovider_aws_secret_key="{{ lookup('env','AWS_SECRET_ACCESS_KEY') }}"
#
#openshift_clusterid=unique_identifier_per_availablility_zone
#
# AWS (Using API Credentials)
#openshift_cloudprovider_kind=aws
#openshift_cloudprovider_aws_access_key=aws_access_key_id
#openshift_cloudprovider_aws_secret_key=aws_secret_access_key
#
# AWS (Using IAM Profiles)
#openshift_cloudprovider_kind=aws
# Note: IAM roles must exist before launching the instances.
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When Ansible configures AWS, the following files are created for you:
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Edit or
create
the master configuration file on all masters
(/etc/origin/master/master-config.yaml by default) and update the contents
of the apiServerArguments and controllerArguments sections:
kubernetesMasterConfig:
...
apiServerArguments:
cloud-provider:
- "aws"
cloud-config:
- "/etc/origin/cloudprovider/aws.conf"
controllerArguments:
cloud-provider:
- "aws"
cloud-config:
- "/etc/origin/cloudprovider/aws.conf"Currently, the nodeName must match the instance name in AWS in order
for the cloud provider integration to work properly. The name must also be
RFC1123 compliant.
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When triggering a containerized installation, only the directories of /etc/origin and /var/lib/origin are mounted to the master and node container. Therefore, aws.conf should be in /etc/origin/ instead of /etc/. |
Edit or
create
the node configuration file on all nodes (/etc/origin/node/node-config.yaml
by default) and update the contents of the kubeletArguments section:
kubeletArguments:
cloud-provider:
- "aws"
cloud-config:
- "/etc/origin/cloudprovider/aws.conf"|
When triggering a containerized installation, only the directories of /etc/origin and /var/lib/origin are mounted to the master and node container. Therefore, aws.conf should be in /etc/origin/ instead of /etc/. |
Make sure the following environment variables are set in the /etc/sysconfig/atomic-openshift-master-api file and /etc/sysconfig/atomic-openshift-master-controllers file on masters and the /etc/sysconfig/atomic-openshift-node file on nodes:
AWS_ACCESS_KEY_ID=<key_ID> AWS_SECRET_ACCESS_KEY=<secret_key>
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Access keys are obtained when setting up your AWS IAM user. |
Start or restart OpenShift Container Platform services on all master and node hosts to apply your configuration changes, see Restarting OpenShift Container Platform services:
# systemctl restart atomic-openshift-master-api atomic-openshift-master-controllers # systemctl restart atomic-openshift-node
Switching from not using a cloud provider to using a cloud provider produces an
error message. Adding the cloud provider tries to delete the node because the
node switches from using the hostname as the externalID (which would have
been the case when no cloud provider was being used) to using the cloud
provider’s instance-id (which is what the cloud provider specifies). To
resolve this issue:
Log in to the CLI as a cluster administrator.
Check and back up existing node labels:
$ oc describe node <node_name> | grep -Poz '(?s)Labels.*\n.*(?=Taints)'Delete the nodes:
$ oc delete node <node_name>On each node host, restart the OpenShift Container Platform service.
# systemctl restart atomic-openshift-node
Add back any labels on each node that you previously had.
Starting with OpenShift Container Platform version 3.7 of the atomic-openshift-installer,
if you configured AWS provider credentials, you must also ensure that all
instances are labeled. This topic describes how to label an existing
OpenShift Container Platform cluster running on AWS.
To correctly identify which resources are associated with a cluster, tag
resources with the key kubernetes.io/cluster/<name>,Value=<clusterid>, where:
<name> is a unique name for the cluster.
<clusterid> is a cluster identifier unique to the AWS Availability Zone.
Tagging all resources with the kubernetes.io/cluster/<name>,Value=<clusterid>
tag avoids potential issues with multiple zones or multiple clusters.
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In versions prior to OpenShift Container Platform version 3.6, this was
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See Pods and Services to learn more about labeling and tagging in OpenShift Container Platform.
There are four types of resources that need to be tagged:
Instances
Security Groups
Load Balancers
EBS Volumes
A cluster uses the value of the kubernetes.io/cluster/<name>,Value=<clusterid> tag to determine which
resources belong to the cluster. Therefore, you must tag all resources with the
key kubernetes.io/cluster/<name>,Value=<clusterid> and have the same value for that key.
Tag all instances with kubernetes.io/cluster/<name>,Value=<clusterid> and a value to be used as the cluster ID.
Tag any security groups with kubernetes.io/cluster/<name>,Value=<clusterid> and the same value used for the instances.
Tag any load balancers with kubernetes.io/cluster/<name>,Value=<clusterid> and the same value used for the instances.
Tag all EBS volumes with kubernetes.io/cluster/<name>,Value=<clusterid> and the same value used for the instances. The EBS Volumes that need to be tagged can found with:
$ oc get pv -o json|jq '.items[].spec.awsElasticBlockStore.volumeID'Restart the master services on the master and the node service on all nodes, see Applying Configuration Section.