Accessing clusters
After your IBM Cloud® Kubernetes Service cluster is created, you can begin working with your cluster by accessing the cluster.
Prerequisites
- Install the required CLI tools, including the IBM Cloud CLI, Kubernetes Service plug-in (
ibmcloud ks
), and Kubernetes CLI (kubectl
). For quick access to test features in your cluster, you can also use the IBM Cloud Shell. - Create your IBM Cloud Kubernetes Service cluster.
- If your network is protected by a company firewall, allow access to the IBM Cloud and IBM Cloud Kubernetes Service API endpoints and ports. For private cloud service endpoint-only clusters, you can't test the connection to your cluster until you configure access to the cloud service endpoint subnet.
- Check that your cluster is in a healthy state by running
ibmcloud ks cluster get -c <cluster_name_or_ID>
. If your cluster is not in a healthy state, review the Debugging clusters guide for help. For example, if your cluster is provisioned in an account that is protected by a firewall gateway appliance, you must configure your firewall settings to allow outgoing traffic to the appropriate ports and IP addresses. - In the output of the cluster details from the previous step, check the Public or Private Service Endpoint URL of the cluster.
- Public Service Endpoint URL only: Continue with Accessing clusters through the public cloud service endpoint.
- Private Service Endpoint URL only: Continue with Accessing clusters through the private cloud service endpoint.
- Both service endpoint URLs: You can access your cluster either through the public or the private service endpoint.
- You can also access your VPC cluster through the Virtual Private Endpoint.
Accessing clusters through the public cloud service endpoint
To work with your cluster, set the cluster that you created as the context for a CLI session to run kubectl
commands.
If you want to use the IBM Cloud console instead, you can run CLI commands directly from your web browser in the IBM Cloud Shell.
- Set the cluster that you created as the context for this session. Complete these configuration steps every time that you work with your cluster.
- Download and add the
kubeconfig
configuration file for your cluster to your existingkubeconfig
in~/.kube/config
or the last file in theKUBECONFIG
environment variable.ibmcloud ks cluster config -c <cluster_name_or_ID>
- Verify that
kubectl
commands run properly and that the Kubernetes context is set to your cluster.
Example outputkubectl config current-context
<cluster_name>/<cluster_ID>
- Download and add the
- Launch your Kubernetes dashboard with the default port
8001
.- Set the proxy with the default port number.
kubectl proxy
Starting to serve on 127.0.0.1:8001
- Open the following URL in a web browser to see the Kubernetes dashboard.
http://localhost:8001/api/v1/namespaces/kube-system/services/https:kubernetes-dashboard:/proxy/
- Set the proxy with the default port number.
Accessing clusters through the private cloud service endpoint
Allow authorized cluster users to access your VPC or classic cluster through the private cloud service endpoint.
Accessing VPC clusters through the private cloud service endpoint
The Kubernetes master is accessible through the private cloud service endpoint if authorized cluster users are in your IBM Cloud private network or are connected to the private network, such as through a VPC VPN connection.
However, communication with the Kubernetes master over the private cloud service endpoint must go through the 166.X.X.X
IP address range, which you must configure in your VPN gateway and connection setup.
-
Set up your IBM Cloud VPC VPN and connect to your private network through the VPN.
- Configure a VPN gateway on your local machine. For example, you might choose to set up strongSwan on your machine.
- Create a VPN gateway in your VPC, and create the connection between the VPC VPN gateway and your local VPN gateway. In the New VPN connection for VPC section, add the
166.8.0.0/14
subnet to the Local subnets field. If you have a multizone cluster, repeat this step to configure a VPC gateway on a subnet in each zone where you have worker nodes. - Verify that you are connected to the private network through your IBM Cloud VPC VPN connection.
-
Download and add the
kubeconfig
configuration file for your cluster to your existingkubeconfig
in~/.kube/config
or the last file in theKUBECONFIG
environment variable.ibmcloud ks cluster config -c <cluster_name_or_ID> --endpoint private
-
Verify that
kubectl
commands run properly and that the Kubernetes context is set to your cluster.kubectl config current-context
Example output
<cluster_name>/<cluster_ID>
Accessing classic clusters through the private cloud service endpoint
The Kubernetes master is accessible through the private cloud service endpoint if authorized cluster users are in your IBM Cloud private network or are connected to the private network such as through a classic VPN connection or IBM Cloud Direct Link. However, communication with the Kubernetes master over the private cloud service endpoint must go through the 166.X.X.X
IP address range,
which is not routable from a classic VPN connection or through IBM Cloud Direct Link. You can expose the private cloud service endpoint of the master for your cluster users by using a private network load balancer (NLB). The private NLB
exposes the private cloud service endpoint of the master as an internal 10.X.X.X
IP address range that users can access with the VPN or IBM Cloud Direct Link connection. If you enable only the private cloud service endpoint,
you can use the Kubernetes dashboard or temporarily enable the public cloud service endpoint to create the private NLB.
-
Get the private cloud service endpoint URL and port for your cluster.
ibmcloud ks cluster get -c <cluster_name_or_ID>
In this example output, the Private Service Endpoint URL is
https://c1.private.us-east.containers.cloud.ibm.com:25073
.NAME: setest ID: b8dcc56743394fd19c9f3db7b990e5e3 State: normal Status: healthy cluster Created: 2019-04-25T16:03:34+0000 Location: wdc04 Master URL: https://c1.private.us-east.containers.cloud.ibm.com:25073 Public Service Endpoint URL: - Private Service Endpoint URL: https://c1.private.us-east.containers.cloud.ibm.com:25073 Master Location: Washington D.C. ...
-
Create a YAML file named
kube-api-via-nlb.yaml
. This YAML creates a privateLoadBalancer
service and exposes the private cloud service endpoint through that NLB. Replace<private_service_endpoint_port>
with the port you found in the previous step.apiVersion: v1 kind: Service metadata: name: kube-api-via-nlb annotations: service.kubernetes.io/ibm-load-balancer-cloud-provider-ip-type: private namespace: default spec: type: LoadBalancer ports: - protocol: TCP port: 8080 # Or, the <private_service_endpoint_port> that you found earlier. targetPort: 8080 # Optional. By default, the `targetPort` is set to match the `port` value unless specified otherwise. --- kind: Endpoints apiVersion: v1 metadata: name: kube-api-via-nlb subsets: - addresses: - ip: 172.20.0.1 ports: - port: 2040
-
To create the private NLB, you must be connected to the cluster master. Because you can't yet connect through the private cloud service endpoint from a VPN or IBM Cloud Direct Link, you must connect to the cluster master and create the NLB by using the public cloud service endpoint or Kubernetes dashboard.
-
If you enabled the private cloud service endpoint only, you can use the Kubernetes dashboard to create the NLB. The dashboard automatically routes all requests to the private cloud service endpoint of the master.
- Log in to the IBM Cloud console.
- From the menu bar, select the account that you want to use.
- From the menu
, click Kubernetes.
- On the Clusters page, click the cluster that you want to access.
- From the cluster detail page, click the Kubernetes Dashboard.
- Click + Create.
- Select Create from file, upload the
kube-api-via-nlb.yaml
file, and click Upload. - In the Overview page, verify that the
kube-api-via-nlb
service is created. In the External endpoints column, note the10.x.x.x
address. This IP address exposes the private cloud service endpoint for the Kubernetes master on the port that you specified in your YAML file.
-
If you also enabled the public cloud service endpoint, you already have access to the master.
- Download and add the
kubeconfig
configuration file for your cluster to your existingkubeconfig
in~/.kube/config
or the last file in theKUBECONFIG
environment variable.ibmcloud ks cluster config -c <cluster_name_or_ID>
- Create the NLB and endpoint.
kubectl apply -f kube-api-via-nlb.yaml
- Verify that the
kube-api-via-nlb
NLB is created. In the output, note the10.x.x.x
EXTERNAL-IP address. This IP address exposes the private cloud service endpoint for the Kubernetes master on the port that you specified in your YAML file.
In this example output, the IP address for the private cloud service endpoint of the Kubernetes master iskubectl get svc -o wide
10.186.92.42
.NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR kube-api-via-nlb LoadBalancer 172.21.150.118 10.186.92.42 443:32235/TCP 10m <none> ...
- Download and add the
-
-
On the client machines where you or your users run
kubectl
commands, add the NLB IP address and the private cloud service endpoint URL to the/etc/hosts
file. Do not include any ports in the IP address and URL and don't includehttps://
in the URL.-
For macOS and Linux users:
sudo nano /etc/hosts
-
For Windows users:
notepad C:\Windows\System32\drivers\etc\hosts
Depending on your local machine permissions, you might need to run Notepad as an administrator to edit the hosts file.
10.186.92.42 c1.private.us-east.containers.cloud.ibm.com
-
-
Verify that you are connected to the private network through a VPN or IBM Cloud Direct Link connection.
-
Download and add the
kubeconfig
configuration file for your cluster to your existingkubeconfig
in~/.kube/config
or the last file in theKUBECONFIG
environment variable.ibmcloud ks cluster config -c <cluster_name_or_ID> --endpoint private
-
Verify that
kubectl
commands run properly and that the Kubernetes context is set to your cluster.kubectl config current-context
Example output
<cluster_name>/<cluster_ID>
Creating an allowlist for the private cloud service endpoint
Control access to your private cloud service endpoint by creating a subnet allowlist.
After you grant users access to your cluster through IBM Cloud IAM, you can add a secondary layer of security by creating an allowlist for the private cloud service endpoint. Only authorized requests to your cluster master that originate from subnets in the allowlist are permitted through the cluster's private cloud service endpoint.
If you want to allow requests from a different VPC than the one your cluster is in, you must include the cloud service endpoint for that VPC in the allowlist.
For example, to access your cluster's private cloud service endpoint, you must connect to your IBM Cloud classic network or your VPC network through a VPN or IBM Cloud Direct Link. You can add the subnet for the VPN or Direct Link tunnel so that only authorized users in your organization can access the private cloud service endpoint from that subnet.
A private cloud service endpoint allowlist can also help prevent users from accessing your cluster after their authorization is revoked. When a user leaves your organization, you remove their IBM Cloud IAM permissions that grant them access to the cluster. However, the user might have copied the API key that contains a functional ID's credentials, which contain the necessary IAM permissions for your cluster. That user can still use those credentials and the private cloud service endpoint address to access your cluster from a different subnet, such as from a different IBM Cloud account. If you create an allowlist that includes only the subnets for your VPN tunnel in your organization's IBM Cloud account, the user's attempted access from another IBM Cloud account is denied.
Worker node subnets are automatically added to and removed from your allowlist so that worker nodes can always access the master through the private cloud service endpoint.
By default, private cloud service endpoint allowlists are limited to 20 subnets. If you need more than 20 subnets in your allowlist, you can [open a support ticket](/docs/containers?topic=containers-get-help to increase the limit to 75.
If the public cloud service endpoint is enabled for your cluster, authorized requests are still permitted through the public cloud service endpoint. Therefore, the private cloud service endpoint allowlist is most effective for controlling access to clusters that have only the private cloud service endpoint enabled.
Before you begin:
- Access your cluster through the private cloud service endpoint.
- Grant users access to your cluster through IBM Cloud IAM.
To create a private cloud service endpoint allowlist:
-
Get the subnets that you want to add to the allowlist. For example, you might get the subnet for the connection through your VPN or Direct Link tunnel to your IBM Cloud private network.
-
Enable the subnet allowlist feature for a cluster's private cloud service endpoint. Now, access to the cluster via the private cloud service endpoint is blocked for any requests that originate from a subnet that is not in the allowlist. Your worker nodes continue to run and have access to the master.
ibmcloud ks cluster master private-service-endpoint allowlist enable --cluster <cluster_name_or_ID>
-
Add subnets from which authorized users can access your private cloud service endpoint to the allowlist.
ibmcloud ks cluster master private-service-endpoint allowlist add --cluster <cluster_name_or_ID> --subnet <subnet_CIDR> [--subnet <subnet_CIDR> ...]
-
Verify that the subnets in your allowlist are correct. The allowlist includes subnets that you manually added and subnets that are automatically added and managed by IBM, such as worker node subnets.
ibmcloud ks cluster master private-service-endpoint allowlist get --cluster <cluster_name_or_ID>
Your authorized users can now continue with Accessing clusters through the private cloud service endpoint.
Accessing VPC clusters through the Virtual Private Endpoint Gateway
Virtual Private Endpoint Gateway is created for VPC clusters automatically. The Kubernetes master is accessible through this Virtual Private Endpoint gateway if authorized cluster users are connected
to the same VPC where the cluster is deployed, such as through a IBM Cloud VPC VPN. In this case, the kubeconfig
is configured with the Virtual Private Endpoint (VPE) URL which is
private DNS name and could be resolved only by the IBM Cloud VPC Private DNS service. The IBM Cloud VPC Private DNS server addresses are 161.26.0.7
and 161.26.0.8
.
-
Set up your IBM Cloud VPC VPN and connect to your VPC through VPN.
- Configure a client-to-site or site-to-site VPN to your VPC. For example, you might choose to set up a client-to-site connection with a VPN Client.
- In case of client-to-site VPN for IBM Cloud VPC service, you must specify the IBM Cloud VPC Private DNS service addresses when you provision the VPN server as mentioned in the considerations,
and you must create a VPN route after the VPN server is provisioned, with destination
161.26.0.0/16
and actiontranslate
. - In case of site-to-site VPN for IBM Cloud VPC service, follow the Accessing service endpoints through VPN guide and configure the IBM Cloud VPC Private DNS service addresses.
- Verify that you are connected to the VPC through your IBM Cloud VPC VPN connection.
-
Download and add the
kubeconfig
configuration file for your cluster to your existingkubeconfig
in~/.kube/config
or the last file in theKUBECONFIG
environment variable.ibmcloud ks cluster config -c <cluster_name_or_ID> --endpoint vpe
-
1.30 and later Add a security group rule to the
kube-vpegw-<clusterID>
for your VPN. The remote resource in this example comes from the VPN’s client IP CIDR. You can find your VPE port by runningibmcloud ks cluster get -c CLUSTER
.ibmcloud is sg-rulec kube-vpegw-<clusterID> inbound tcp --port-min 30829 --port-max 30829 --remote 192.168.192.0/22
-
Verify that the Kubernetes context is set to your cluster.
kubectl config current-context
Example output
<cluster_name>/<cluster_ID>
kubectl version
Example output
Client Version: v1.25.3 Kustomize Version: v4.5.7 Server Version: v1.25.4+IKS