In this lab you will complete a series of tasks to ensure your Kubernetes cluster is functioning correctly.
In this section you will verify the ability to encrypt secret data at rest.
Create a generic secret:
kubectl create secret generic kubernetes-the-hard-way \
--from-literal="mykey=mydata"
Print a hexdump of the kubernetes-the-hard-way
secret stored in etcd:
ssh root@controller-0 \
sudo ETCDCTL_API=3 etcdctl get \
--endpoints=https://127.0.0.1:2379 \
--cacert=/etc/etcd/ca.pem \
--cert=/etc/etcd/kubernetes.pem \
--key=/etc/etcd/kubernetes-key.pem\
/registry/secrets/default/kubernetes-the-hard-way | hexdump -C
Output:
00000000 2f 72 65 67 69 73 74 72 79 2f 73 65 63 72 65 74 |/registry/secret|
00000010 73 2f 64 65 66 61 75 6c 74 2f 6b 75 62 65 72 6e |s/default/kubern|
00000020 65 74 65 73 2d 74 68 65 2d 68 61 72 64 2d 77 61 |etes-the-hard-wa|
00000030 79 0a 6b 38 73 3a 65 6e 63 3a 61 65 73 63 62 63 |y.k8s:enc:aescbc|
00000040 3a 76 31 3a 6b 65 79 31 3a 44 ac 6e ac 11 2f 28 |:v1:key1:D.n../(|
00000050 02 46 3d ad 9d cd 68 be e4 cc 63 ae 13 e4 99 e8 |.F=...h...c.....|
00000060 6e 55 a0 fd 9d 33 7a b1 17 6b 20 19 23 dc 3e 67 |nU...3z..k .#.>g|
00000070 c9 6c 47 fa 78 8b 4d 28 cd d1 71 25 e9 29 ec 88 |.lG.x.M(..q%.)..|
00000080 7f c9 76 b6 31 63 6e ea ac c5 e4 2f 32 d7 a6 94 |..v.1cn..../2...|
00000090 3c 3d 97 29 40 5a ee e1 ef d6 b2 17 01 75 a4 a3 |<=.)@Z.......u..|
000000a0 e2 c2 70 5b 77 1a 0b ec 71 c3 87 7a 1f 68 73 03 |..p[w...q..z.hs.|
000000b0 67 70 5e ba 5e 65 ff 6f 0c 40 5a f9 2a bd d6 0e |gp^.^e.o.@Z.*...|
000000c0 44 8d 62 21 1a 30 4f 43 b8 03 69 52 c0 b7 2e 16 |D.b!.0OC..iR....|
000000d0 14 a5 91 21 29 fa 6e 03 47 e2 06 25 45 7c 4f 8f |...!).n.G..%E|O.|
000000e0 6e bb 9d 3b e9 e5 2d 9e 3e 0a |n..;..-.>.|
The etcd key should be prefixed with k8s:enc:aescbc:v1:key1
, which indicates the aescbc
provider was used to encrypt the data with the key1
encryption key.
In this section you will verify the ability to create and manage Deployments.
Create a deployment for the nginx web server:
kubectl create deployment nginx --image=nginx
List the pod created by the nginx
deployment:
kubectl get pods -l app=nginx
Output (you may need to wait a few seconds to see the pod "READY"):
NAME READY STATUS RESTARTS AGE
nginx-554b9c67f9-vt5rn 1/1 Running 0 10s
In this section you will verify the ability to access applications remotely using port forwarding.
Retrieve the full name of the nginx
pod:
POD_NAME=$(kubectl get pods -l app=nginx -o jsonpath="{.items[0].metadata.name}")
Forward port 8080
on your local machine to port 80
of the nginx
pod:
kubectl port-forward $POD_NAME 8080:80
Output:
Forwarding from 127.0.0.1:8080 -> 80
Forwarding from [::1]:8080 -> 80
In a new terminal make an HTTP request using the forwarding address:
curl --head http://127.0.0.1:8080
Output:
HTTP/1.1 200 OK
Server: nginx/1.19.0
Date: Wed, 24 Jun 2020 12:55:15 GMT
Content-Type: text/html
Content-Length: 612
Last-Modified: Tue, 26 May 2020 15:00:20 GMT
Connection: keep-alive
ETag: "5ecd2f04-264"
Accept-Ranges: bytes
Switch back to the previous terminal and stop the port forwarding to the nginx
pod:
Forwarding from 127.0.0.1:8080 -> 80
Forwarding from [::1]:8080 -> 80
Handling connection for 8080
^C
In this section you will verify the ability to retrieve container logs.
Print the nginx
pod logs:
kubectl logs $POD_NAME
Output:
127.0.0.1 - - [24/Jun/2020:12:55:15 +0000] "HEAD / HTTP/1.1" 200 0 "-" "curl/7.64.0" "-"
In this section you will verify the ability to execute commands in a container.
Print the nginx version by executing the nginx -v
command in the nginx
container:
kubectl exec -ti $POD_NAME -- nginx -v
Output:
nginx version: nginx/1.19.0
In this section you will verify the ability to expose applications using a Service.
Expose the nginx
deployment using a NodePort service:
kubectl expose deployment nginx --port 80 --type NodePort
The LoadBalancer service type can not be used because your cluster is not configured with. It is out of scope for this tutorial.
Retrieve the node port assigned to the nginx
service:
NODE_PORT=$(kubectl get svc nginx \
--output=jsonpath='{range .spec.ports[0]}{.nodePort}')
Define the Kubernetes network IP address of a worker instance (replace MY_WORKER_IP with the private IP defined on a worker):
NODE_IP=MY_WORKER_IP
Example for worker-0: 192.168.8.20
Make an HTTP request using the external IP address and the nginx
node port:
curl -I http://${NODE_IP}:${NODE_PORT}
Output:
HTTP/1.1 200 OK
Server: nginx/1.19.0
Date: Wed, 24 Jun 2020 12:57:37 GMT
Content-Type: text/html
Content-Length: 612
Last-Modified: Tue, 26 May 2020 15:00:20 GMT
Connection: keep-alive
ETag: "5ecd2f04-264"
Accept-Ranges: bytes
Next: Cleaning Up