Lab 1. Deploy your first application¶
Learn how to deploy an application to a Kubernetes cluster hosted within the IBM Container Service.
Make sure you satisfy the prerequisites as outlined in Lab 0
$ ibmcloud cs cluster-create --name <name-of-cluster>
If the above command doesn't work, please try the command below：
$ ibmcloud cs cluster create classic --name <name-of-cluseter>
Once the cluster is provisioned, the kubernetes client CLI
kubectl needs to be
configured to talk to the provisioned cluster.
$ ibmcloud cs cluster-config <name-of-cluster>, and set the
KUBECONFIGenvironment variable based on the output of the command. This will make your
kubectlclient point to your new Kubernetes cluster.
Once your client is configured, you are ready to deploy your first application,
1. Deploy the guestbook application¶
In this part of the lab we will deploy an application called
that has already been built and uploaded to DockerHub under the name
- Start by running
kubectl create deployment guestbook --image=ibmcom/guestbook:v1
This action will take a bit of time. To check the status of the running application,
you can use
$ kubectl get pods.
You should see output similar to the following:
kubectl get pods
Eventually, the status should show up as
$ kubectl get pods NAME READY STATUS RESTARTS AGE guestbook-59bd679fdc-bxdg7 1/1 Running 0 1m
The end result of the run command is not just the pod containing our application containers, but a Deployment resource that manages the lifecycle of those pods.
- Once the status reads
Running, we need to expose that deployment as a service so we can access it through the IP of the worker nodes. The
guestbookapplication listens on port 3000. Run:
kubectl expose deployment guestbook --type="NodePort" --port=3000
- To find the port used on that worker node, examine your new service:
$ kubectl get service guestbook NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE guestbook NodePort 10.10.10.253 <none> 3000:31208/TCP 1m
We can see that our
31208. We can see in the output the port mapping from 3000 inside
the pod exposed to the cluster on port 31208. This port in the 31000 range is automatically chosen,
and could be different for you.
guestbookis now running on your cluster, and exposed to the internet. We need to find out where it is accessible. The worker nodes running in the container service get external IP addresses. Get the workers for your cluster and note one (any one) of the public IPs listed on the
$CLUSTER_NAMEwith your cluster name unless you have this environment variable set.
$ kubectl get nodes -o wide NAME STATUS ROLES AGE VERSION INTERNAL-IP EXTERNAL-IP OS-IMAGE KERNEL-VERSION CONTAINER-RUNTIME 10.185.199.3 Ready master,worker 63d v1.16.2+283af84 10.185.199.3 220.127.116.11 Red Hat 3.10.0-1127.13.1.el7.x86_64 cri-o://1.16.6-17.rhaos4.3.git4936f44.el7 10.185.199.6 Ready master,worker 63d v1.16.2+283af84 10.185.199.6 18.104.22.168 Red Hat 3.10.0-1127.13.1.el7.x86_64 cri-o://1.16.6-17.rhaos4.3.git4936f44.el7
We can see that our
- Now that you have both the address and the port, you can now access the application in the web browser
<public-IP>:<nodeport>. In the example case this is
Congratulations, you've now deployed an application to Kubernetes!
When you're all done, continue to the next lab of this course.