Decommissioning

Decommissioning a cluster requires only a few commands, but beware that it will irretrievably destroy the cluster, its workloads and any information that was stored within. Before proceeding, it is important to verify that you:

• Have the correct details for the cluster you wish to decommission
• Have retrieved any valuable data from the cluster

Destroying the model

It is always preferable to use a new Juju model for each Kubernetes cluster. Removing the model is then a simple operation.

It is useful to list all the current models to make sure you are about to destroy the correct one:

juju models

This will list all the models running on the current controller, for example:

Controller: k8s-controller

Model           Cloud/Region   Status     Machines  Cores  Access  Last connection
controller      aws/us-east-1  available   1          4     admin   just now
default         aws/us-east-1  available   0          -     admin   8 hours ago
k8s-devel       aws/us-east-1  available   9         24     admin   3 hours ago
k8s-production  aws/us-east-1  available  12         28     admin   5 minutes ago
k8s-testing     aws/us-east-1  available   9         24     admin   2 hours ago

To proceed, use the juju destroy-model command to target the model you wish to remove. For example:

 juju destroy-model k8s-testing

You will see a warning, and be required to confirm the action. Juju will then continue to free up the resources, giving feedback on the process. It may take some minutes to complete depending on the size of the deployed model and the nature of the cloud it is running on.

WARNING! This command will destroy the "k8s-testing" model.
This includes all machines, applications, data and other resources.

Continue [y/N]? y
Destroying model
Waiting on model to be removed, 7 machine(s), 4 application(s)...
Waiting on model to be removed, 6 machine(s)...
...
Waiting on model to be removed, 3 machine(s)...
Waiting on model to be removed...
Model destroyed.

You should confirm that the cloud instances have been terminated with the relevant cloud console/utilities.

Destroying a controller

If there are no longer any cluster models attached to the controller, you may wish to remove the controller instance as well. This is performed with a similar command:

juju destroy-controller <controller-name>

As previously, there is a confirmation step to make sure you wish to remove the controller.

The command will return an error if there are populated models still attached to the controller.

Removing/editing Kube config

If you have permanently removed clusters, it is also advisable to remove their entries in the Kubernetes configuration file (or remove the file entirely if you have removed all the clusters).

By default the file is located at ~/.kube/config. It is a YAML format file, and each cluster block looks similar to this:

- cluster:
    certificate-authority-data:
       LS0tLS1CRUdJTiBDRVJUSUZJQ0FURS0tLS0tCk1JSURPekNDQWlPZ0F3SUJBZ0lKQU9HTm9
       PM1pNb3RGTUEwR0NTcUdTSWIzRFFFQkN3VUFNQmd4RmpBVUJnTlYKQkFNTURUTTBMakkwTk
       M0eE9USXVORGt3SGhjTk1UZ3hNREF4TURnek5qVTFXaGNOTWpnd09USTRNRGd6TmpVMQpXa
       kFZTVJZd0ZBWURWUVFEREEwek5DNHlORFF1TVRreUxqUTVNSUlCSWpBTkJna3Foa2lHOXcw
       QkFRRUZBQU9DCkFROEFNSUlCQ2dLQ0FRRUE4YThJVytCUTM5c0p3OENyR0c5MmlYSUlWczN
       QOElEVVJvOTMyVFVYcG05UWkwSUgKeVF0a2N1WEVpREhlbUgwK1RORHRmaFZ4cm9BRjQrVE
       czR3JWZXc0YzgrZE0zNWJMY0lMRkl1L1UydlR4NkRXbgpDa2lwblhJVlc1QUxXa1hqRUh3N
       TUvWnk3S0F2SjVjS0h5WnhMYzY1ZFZqVjJYNkQxRHhJRXh0c2dDVnB2R1gvCmRpK1ppZlJX
       eFIwR0l5SkM3b29VaEVjcitvQVpMOFc2YklUMUlwcklXUGQ1eWhJck10MmpmaE42NWVkV1h
       jYkoKNERQeEpIOVlDNFFqSC84OHNJdWVJMWo4S1NYQjdwbUJxMzJHYXZuaFp3K2M5bG1KSl
       E5WjNZM2dla3lBUlZDRQpwUUU5T3BYR01QOCtCdng4QXdrQW9obE83RE1xQTlMaTl3QXExU
       UlEQVFBQm80R0hNSUdFTUIwR0ExVWREZ1FXCkJCUXRaa3paWmxKSmZKMGZtbWNPZU9pR0VB
       L3d1REJJQmdOVkhTTUVRVEEvZ0JRdFprelpabEpKZkowZm1tY08KZU9pR0VBL3d1S0VjcEJ
       vd0dERVdNQlFHQTFVRUF3d05NelF1TWpRMExqRTVNaTQwT1lJSkFPR05vTzNaTW90RgpNQX
       dHQTFVZEV3UUZNQU1CQWY4d0N3WURWUjBQQkFRREFnRUdNQTBHQ1NxR1NJYjNEUUVCQ3dVQ
       UE0SUJBUUJnCjVndFpyY0FLUlFSYUJFZDFiVm5vRXpoZkxld2RXU2RYaEZGRXB6bjlzdG05
       VGdVM2ZLREJ0NktUY3JKN2hqQWQKMUlUbUc1L2ExaUlDM29qQ2d3c1o3cnFmRlhkRGQzcVZ
       GdjJySmZEN2ljeGV2c0NjWTdiS1hlYy9QdVgxQmxlMwo1amRjSWRkZnhqZ1M3K2dibCtQcG
       owbm9OR0c5MUgydWtBWTlaei9FUHdZckhuV1V1V1o5Z3JTZlVGam1ZMTNWCjkxZmF0S2R2d
       lU1blFPUXdkdThPVHlFRGk2blA4ckN4bEJjRW1hN3hkM3c5djI0NUlaRnd5QTJBMlR6emFJ
       M04KYm0vMVNyL2tTNlZCSi9sZ2s3ampxRWFicmpFakluMlU4aGkzRkluRnBkZkZlUXhBaW5
       JcUx5dGRzeXY5aFZVbQpKQ3luNW8yaGVjSTFsaDU3RFRtYQotLS0tLUVORCBDRVJUSUZJQ0
       FURS0tLS0t
    server: https://54.229.190.254:443
  name: conjure-canonical-kubern-fc3
contexts:
- context:
    cluster: conjure-canonical-kubern-fc3
    user: conjure-canonical-kubern-fc3
  name: conjure-canonical-kubern-fc3
current-context: conjure-canonical-kubern-fc3
kind: Config
preferences: {}
users:
- name: conjure-canonical-kubern-fc3
  user:
    password: sZVKhY7bZK8oG7vLkkOssNhTzKZlBmcG
    username: admin