Add dashboard section + kubectl apply sec talk

docs/dashboard.md

@@ -0,0 +1,179 @@
+# The Kubernetes dashboard
+
+- Kubernetes resources can also be viewed with a web dashboard
+
+- We are going to deploy that dashboard with *three commands:*
+
+  - one to actually *run* the dashboard
+
+  - one to make the dashboard available from outside
+
+  - one to bypass authentication for the dashboard
+
+--
+
+.footnote[.warning[Yes, this will open our cluster to all kinds of shenanigans. Don't do this at home.]]
+
+---
+
+## Running the dashboard
+
+- We need to create a *deployment* and a *service* for the dashboard
+
+- But also a *secret*, a *service account*, a *role* and a *role binding*
+
+- All these things can be defined in a YAML file and created with `kubectl apply -f`
+
+.exercise[
+
+- Create all the dashboard resources, with the following command:
+  ```bash
+  kubectl apply -f https://goo.gl/Qamqab
+  ```
+
+]
+
+The goo.gl URL expands to:
+<br/>
+.small[https://raw.githubusercontent.com/kubernetes/dashboard/master/src/deploy/recommended/kubernetes-dashboard.yaml]
+
+---
+
+## Making the dashboard reachable from outside
+
+- The dashboard is exposed through a `ClusterIP` service
+
+- We need a `NodePort` service instead
+
+.exercise[
+
+- Edit the service:
+  ```bash
+  kubectl edit service kubernetes-dashboard
+  ```
+
+]
+
+--
+
+`NotFound`?!? Y U NO WORK?!?
+
+---
+
+## Editing the `kubernetes-dashboard` service
+
+- If we look at the YAML that we loaded just before, we'll get a hint
+
+--
+
+- The dashboard was created in the `kube-system` namespace
+
+.exercise[
+
+- Edit the service:
+  ```bash
+  kubectl -n kube-system edit service kubernetes-dashboard
+  ```
+
+- Change `ClusterIP` to `NodePort`, save, and exit
+
+- Check the port that was assigned with `kubectl -n kube-system get services`
+
+]
+
+---
+
+## Connecting to the dashboard
+
+.exercise[
+
+- Connect to https://oneofournodes:3xxxx/
+
+  (You will have to work around the TLS certificate validation warning)
+
+]
+
+- We have three authentication options at this point:
+
+  - token (associated with a role that has appropriate permissions)
+
+  - kubeconfig (e.g. using the `~/.kube/config` file from `node1`)
+
+  - "skip" (use the dashboard "service account")
+
+- Let's use "skip": we get a bunch of warnings and don't see much
+
+---
+
+## Granting more rights to the dashboard
+
+- The dashboard documentation [explains how to do](https://github.com/kubernetes/dashboard/wiki/Access-control#admin-privileges)
+
+- We just need to load another YAML file!
+
+.exercise[
+
+- Grant admin privileges to the dashboard so we can see our resources:
+  ```bash
+  kubectl apply -f https://goo.gl/CHsLTA
+  ```
+
+- Reload the dashboard and enjoy!
+
+]
+
+--
+
+.warning[By the way, we just added a backdoor to our Kubernetes cluster!]
+
+---
+
+# Security implications of `kubectl apply`
+
+- When we do `kubectl apply -f <URL>`, we create arbitrary resources
+
+- Resources can be evil; imagine a `deployment` that ...
+
+--
+
+  - starts bitcoin miners on the whole cluster
+
+--
+
+  - hides in a non-default namespace
+
+--
+
+  - bind-mounts our nodes' filesystem
+
+--
+
+  - inserts SSH keys in the root account (on the node)
+
+--
+
+  - encrypts our data and ransoms it
+
+--
+
+  - ☠️☠️☠️
+
+---
+
+## `kubectl apply` is the new `curl | sh`
+
+- `curl | sh` is convenient
+
+- It's safe if you use HTTPS URLs from trusted sources
+
+--
+
+- `kubectl apply -f` is convenient
+
+- It's safe if you use HTTPS URLs from trusted sources
+
+--
+
+- It introduces new failure modes
+
+- Example: the official setup instructions for most pod networks

docs/kube.yml

@@ -70,6 +70,7 @@ chapters:
   - kubectlrun.md
 - - kubectlexpose.md
   - ourapponkube.md
+  - dashboard.md
 - - kubectlscale.md
   - daemonset.md
   - rollout.md