Managed Kubernetes
Capsule Operator can be easily installed on a Managed Kubernetes Service. Since you do not have access to the Kubernetes APIs Server, you should check with the provider of the service:
the default cluster-admin ClusterRole is accessible the following Admission Webhooks are enabled on the APIs Server:
PodNodeSelectorLimitRangerResourceQuotaMutatingAdmissionWebhookValidatingAdmissionWebhook
AWS EKS
This is an example of how to install AWS EKS cluster and one user manged by Capsule. It is based on Using IAM Groups to manage Kubernetes access
Create EKS cluster:
export AWS_DEFAULT_REGION="eu-west-1"
export AWS_ACCESS_KEY_ID="xxxxx"
export AWS_SECRET_ACCESS_KEY="xxxxx"
eksctl create cluster \
--name=test-k8s \
--managed \
--node-type=t3.small \
--node-volume-size=20 \
--kubeconfig=kubeconfig.conf
Create AWS User alice using CloudFormation, create AWS access files and kubeconfig for such user:
cat > cf.yml << EOF
Parameters:
ClusterName:
Type: String
Resources:
UserAlice:
Type: AWS::IAM::User
Properties:
UserName: !Sub "alice-${ClusterName}"
Policies:
- PolicyName: !Sub "alice-${ClusterName}-policy"
PolicyDocument:
Version: "2012-10-17"
Statement:
- Sid: AllowAssumeOrganizationAccountRole
Effect: Allow
Action: sts:AssumeRole
Resource: !GetAtt RoleAlice.Arn
AccessKeyAlice:
Type: AWS::IAM::AccessKey
Properties:
UserName: !Ref UserAlice
RoleAlice:
Type: AWS::IAM::Role
Properties:
Description: !Sub "IAM role for the alice-${ClusterName} user"
RoleName: !Sub "alice-${ClusterName}"
AssumeRolePolicyDocument:
Version: 2012-10-17
Statement:
- Effect: Allow
Principal:
AWS: !Sub "arn:aws:iam::${AWS::AccountId}:root"
Action: sts:AssumeRole
Outputs:
RoleAliceArn:
Description: The ARN of the Alice IAM Role
Value: !GetAtt RoleAlice.Arn
Export:
Name:
Fn::Sub: "${AWS::StackName}-RoleAliceArn"
AccessKeyAlice:
Description: The AccessKey for Alice user
Value: !Ref AccessKeyAlice
Export:
Name:
Fn::Sub: "${AWS::StackName}-AccessKeyAlice"
SecretAccessKeyAlice:
Description: The SecretAccessKey for Alice user
Value: !GetAtt AccessKeyAlice.SecretAccessKey
Export:
Name:
Fn::Sub: "${AWS::StackName}-SecretAccessKeyAlice"
EOF
eval aws cloudformation deploy --capabilities CAPABILITY_NAMED_IAM \
--parameter-overrides "ClusterName=test-k8s" \
--stack-name "test-k8s-users" --template-file cf.yml
AWS_CLOUDFORMATION_DETAILS=$(aws cloudformation describe-stacks --stack-name "test-k8s-users")
ALICE_ROLE_ARN=$(echo "${AWS_CLOUDFORMATION_DETAILS}" | jq -r ".Stacks[0].Outputs[] | select(.OutputKey==\"RoleAliceArn\") .OutputValue")
ALICE_USER_ACCESSKEY=$(echo "${AWS_CLOUDFORMATION_DETAILS}" | jq -r ".Stacks[0].Outputs[] | select(.OutputKey==\"AccessKeyAlice\") .OutputValue")
ALICE_USER_SECRETACCESSKEY=$(echo "${AWS_CLOUDFORMATION_DETAILS}" | jq -r ".Stacks[0].Outputs[] | select(.OutputKey==\"SecretAccessKeyAlice\") .OutputValue")
eksctl create iamidentitymapping --cluster="test-k8s" --arn="${ALICE_ROLE_ARN}" --username alice --group capsule.clastix.io
cat > aws_config << EOF
[profile alice]
role_arn=${ALICE_ROLE_ARN}
source_profile=alice
EOF
cat > aws_credentials << EOF
[alice]
aws_access_key_id=${ALICE_USER_ACCESSKEY}
aws_secret_access_key=${ALICE_USER_SECRETACCESSKEY}
EOF
eksctl utils write-kubeconfig --cluster=test-k8s --kubeconfig="kubeconfig-alice.conf"
cat >> kubeconfig-alice.conf << EOF
- name: AWS_PROFILE
value: alice
- name: AWS_CONFIG_FILE
value: aws_config
- name: AWS_SHARED_CREDENTIALS_FILE
value: aws_credentials
EOF
Export “admin” kubeconfig to be able to install Capsule:
export KUBECONFIG=kubeconfig.conf
Install Capsule and create a tenant where alice has ownership. Use the default Tenant example:
kubectl apply -f https://raw.githubusercontent.com/clastix/capsule/master/config/samples/capsule_v1beta1_tenant.yaml
Based on the tenant configuration above the user alice should be able to create namespace. Switch to a new terminal and try to create a namespace as user alice:
# Unset AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY if defined
unset AWS_ACCESS_KEY_ID
unset AWS_SECRET_ACCESS_KEY
kubectl create namespace test --kubeconfig="kubeconfig-alice.conf"
Azure AKS
This reference implementation introduces the recommended starting (baseline) infrastructure architecture for implementing a multi-tenancy Azure AKS cluster using Capsule. See CoAKS.
Charmed Kubernetes
Canonical Charmed Kubernetes is a Kubernetes distribution coming with out-of-the-box tools that support deployments and operational management and make microservice development easier. Combined with Capsule, Charmed Kubernetes allows users to further reduce the operational overhead of Kubernetes setup and management.
The Charm package for Capsule is available to Charmed Kubernetes users via Charmhub.io.