2022-11-07 15:52:54 +11:00

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# Introduction to Sealed Secrets
Checkout the [Sealed Secrets GitHub Repo](https://github.com/bitnami-labs/sealed-secrets) </br>
## Create a kubernetes cluster
In this guide we we''ll need a Kubernetes cluster for testing. Let's create one using [kind](https://kind.sigs.k8s.io/) </br>
```
kind create cluster --name sealedsecrets --image kindest/node:v1.23.5
```
See cluster up and running:
```
kubectl get nodes
NAME STATUS ROLES AGE VERSION
sealedsecrets-control-plane Ready control-plane,master 2m12s v1.23.5
```
## Run a container to work in
### run Alpine Linux:
```
docker run -it --rm -v ${HOME}:/root/ -v ${PWD}:/work -w /work --net host alpine sh
```
### install kubectl
```
apk add --no-cache curl
curl -LO https://storage.googleapis.com/kubernetes-release/release/`curl -s https://storage.googleapis.com/kubernetes-release/release/stable.txt`/bin/linux/amd64/kubectl
chmod +x ./kubectl
mv ./kubectl /usr/local/bin/kubectl
```
### test cluster access:
```
/work # kubectl get nodes
NAME STATUS ROLES AGE VERSION
sealedsecrets-control-plane Ready control-plane,master 3m26s v1.23.5
```
## Install Sealed Secret Controller
### download the YAML
In this demo we'll use version [0.19.1](https://github.com/bitnami-labs/sealed-secrets/releases/download/v0.19.1/controller.yaml) of the sealed secrets controller downloaded from the
[Github releases](https://github.com/bitnami-labs/sealed-secrets/releases) page
```
curl -L -o ./kubernetes/secrets/sealed-secrets/controller-v0.19.1.yaml https://github.com/bitnami-labs/sealed-secrets/releases/download/v0.19.1/controller.yaml
```
### alternative install Helm
TODO: cover helm https://github.com/bitnami-labs/sealed-secrets#helm-chart
### install the controller
```
kubectl apply -f kubernetes/secrets/sealed-secrets/controller-v0.19.1.yaml
```
### Check the install
```
kubectl -n kube-system get pods
```
TODO: check the logs with `kubectl -n kube-system logs` command
TODO: important logs
```
2022/11/05 21:38:20 New key written to kube-system/sealed-secrets-keymwzn9
2022/11/05 21:38:20 Certificate is
-----BEGIN CERTIFICATE-----
< cert content >
-----END CERTIFICATE-----
2022/11/05 21:38:20 HTTP server serving on :808
```
TODO: check our secret
```
kubectl get secret -n kube-system sealed-secrets-keymwzn9 -o yaml
```
## Download KubeSeal
The same way we downloaded the sealed secrets controller from the [GitHub releases](https://github.com/bitnami-labs/sealed-secrets/releases) page,
we'll want to download kubeseal from the assets section
```
curl -L -o /tmp/kubeseal.tar.gz \
https://github.com/bitnami-labs/sealed-secrets/releases/download/v0.19.1/kubeseal-0.19.1-linux-amd64.tar.gz
apk add tar
tar -xzf /tmp/kubeseal.tar.gz -C /tmp/
chmod +x /tmp/kubeseal
mv /tmp/kubeseal /usr/local/bin/
```
### run kubeseal
We can now run `kubeseal --help`
## Sealing a basic Kubernetes Secret
Looks at our existing Kubernetes secret YAML
```
cat kubernetes/secrets/secret.yaml
```
Create a sealed secret using `stdin`
```
cat kubernetes/secrets/secret.yaml | kubeseal -o yaml > kubernetes/secrets/sealed-secrets/sealed-secret.yaml
```
Create a sealed secret using file
```
kubeseal -f kubernetes/secrets/secret.yaml -o yaml > kubernetes/secrets/sealed-secrets/sealed-secret.yaml
```
Deploy the sealed secret
```
kubectl apply -f kubernetes/secrets/sealed-secrets/sealed-secret.yaml
sealedsecret.bitnami.com/mysecret created
```
Now few seconds later, see the secret
```
kubectl -n default get secret
NAME TYPE DATA AGE
mysecret Opaque 1 25s
```
## How the encryption key is managed
TODO: How the encryption key is managed and stored
TODO: Set a duration to test `--key-renew-period=<value>`
```
apk add nano
export KUBE_EDITOR=nano
```
Set the flag on the command like so to add a new key every 5 min for testing:
```
spec:
containers:
- command:
- controller
- --key-renew-period=5m
kubectl edit deployment/sealed-secrets-controller --namespace=kube-system
```
You should see a new key created under secrets in the `kube-system` namespace
```
kubectl -n kube-system get secrets
```
## Backup your encryption keys
TODO: * backup encryption keys
TODO: migrating kubernetes clusters
```
kubectl get secret -n kube-system \
-l sealedsecrets.bitnami.com/sealed-secrets-key \
-o yaml \
> kubernetes/secrets/sealed-secrets/sealed-secret-keys.key
```
## Migrate your encryption keys to a new cluster
Delete & Deploy a new Kubernetes cluster
```
kind delete cluster --name sealedsecrets
kind create cluster --name sealedsecrets --image kindest/node:v1.23.5
# check the cluster
kubectl get nodes
# redeploy sealed-secrets controller
kubectl apply -f kubernetes/secrets/sealed-secrets/controller-v0.19.1.yaml
kubectl -n kube-system get pods
```
### restore our encryption keys
```
kubectl apply -f kubernetes/secrets/sealed-secrets/sealed-secret-keys.key
```
restart the controller:
```
kubectl delete pod -n kube-system -l name=sealed-secrets-controller
```
### apply our old sealed secret
```
kubectl apply -f kubernetes/secrets/sealed-secrets/sealed-secret.yaml
```
TODO: Encrypted sealed secrets across namespaces https://github.com/bitnami-labs/sealed-secrets#scopes
## Re-encrypting secrets with the latest key
```
kubeseal --re-encrypt <my_sealed_secret.json >tmp.json \
&& mv tmp.json my_sealed_secret.json
```