Merge branch 'improve-install'

README.md

@@ -169,9 +169,8 @@ Once applied, check for `node` pod(s) in the `zeropod-system` namespace. If
 everything worked it should be in status `Running`:
 
 ```bash
-$ kubectl get pods -n zeropod-system
-NAME                 READY   STATUS    RESTARTS   AGE
-zeropod-node-zr8k7   2/2     Running   0          35s
+$ kubectl -n zeropod-system wait --for=condition=Ready pod -l app.kubernetes.io/name=zeropod-node
+pod/zeropod-node-wgzrv condition met
 ```
 
 Now you can create workloads which make use of zeropod.
@@ -186,6 +185,18 @@ match yours. In this case you need clone the repo and adjust the manifests in
 `config/` accordingly. If your setup is common, a PR to add your configuration
 adjustments would be most welcome.
 
+### Uninstalling
+
+To uninstall zeropod, you can apply the uninstall manifest to spawn a pod to
+do the cleanup on all labelled zeropod nodes. After all the uninstall pods
+have finished, we can delete all the manifests.
+
+```bash
+kubectl apply -k https://github.com/ctrox/zeropod/config/uninstall
+kubectl -n zeropod-system wait --for=condition=Ready pod -l app.kubernetes.io/name=zeropod-node
+kubectl delete -k https://github.com/ctrox/zeropod/config/production
+```
+
 ## Configuration
 
 A pod can make use of zeropod only if the `runtimeClassName` is set to
@@ -273,24 +284,6 @@ zeropod_restore_duration_seconds_count{container="nginx",namespace="default",pod
 zeropod_running{container="nginx",namespace="default",pod="nginx"} 0
 ```
 
-## TODO
-
-- [x] Support more than 1 container in a zeropod
-	- [x] Support scaling more than 1 container in a zeropod (use-cases might be limited here)
-- [x] Fix logs after restore
-- [ ] Visibility into state (scaled down or up) from the outside
-	- [ ] k8s events?
-	- [x] Metrics
-	- [ ] Custom resource that syncs with a zeropod?
-- [x] Create installer DaemonSet (runtime shim, containerd config, criu binary)
-- [x] e2e testing
-- [x] Scale down/up on demand instead of time based
-	- [x] technically scaling up on demand is now possible with exec. You can just exec a non-existing process.
-- [x] Less configuration - try to detect the port(s) a contanier is listening on
-- [x] Configurable installer (paths etc.)
-- [ ] Create uninstaller
-- [ ] Create issues instead of this list
-
 ## Development
 
 For iterating on shim development it's recommended to use

cmd/installer/main.go

@@ -8,10 +8,8 @@ import (
 	"log"
 	"os"
 	"os/exec"
-	"os/signal"
 	"path"
 	"path/filepath"
-	"syscall"
 	"time"
 
 	"github.com/containerd/containerd"
@@ -92,7 +90,6 @@ func main() {
 		}
 
 		log.Println("uninstaller completed")
-		// we exit after uninstall as this should be run as a one-time job
 		os.Exit(0)
 	}
 
@@ -115,16 +112,6 @@ func main() {
 	log.Println("installed runtimeClass")
 
 	log.Println("installer completed")
-
-	go func() {
-		for {
-			time.Sleep(time.Second)
-		}
-	}()
-
-	quitChannel := make(chan os.Signal, 1)
-	signal.Notify(quitChannel, syscall.SIGINT, syscall.SIGTERM)
-	<-quitChannel
 }
 
 func installCriu(ctx context.Context) error {

config/base/node-daemonset.yaml

@@ -17,16 +17,7 @@ spec:
       serviceAccountName: zeropod-node
       nodeSelector:
         zeropod.ctrox.dev/node: "true"
-      containers:
-        - name: manager
-          image: manager
-          imagePullPolicy: IfNotPresent
-          ports:
-            - name: metrics
-              containerPort: 8080
-          volumeMounts:
-            - mountPath: /run/zeropod
-              name: zeropod-run
+      initContainers:
         - name: installer
           image: installer
           args: []
@@ -42,6 +33,16 @@ spec:
               name: systemd-run
             - mountPath: /etc/criu
               name: criu-etc
+      containers:
+        - name: manager
+          image: manager
+          imagePullPolicy: IfNotPresent
+          ports:
+            - name: metrics
+              containerPort: 8080
+          volumeMounts:
+            - mountPath: /run/zeropod
+              name: zeropod-run
       tolerations:
         - key: kubernetes.io/arch
           operator: Equal
@@ -54,12 +55,12 @@ spec:
         - name: containerd-run
           hostPath:
             path: /run/containerd
-        - name: zeropod-run
-          hostPath:
-            path: /run/zeropod
         - name: zeropod-opt
           hostPath:
             path: /opt/zeropod
+        - name: zeropod-run
+          hostPath:
+            path: /run/zeropod
         - name: systemd-run
           hostPath:
             path: /run/systemd

config/gke/kustomization.yaml

@@ -5,7 +5,7 @@ patchesStrategicMerge:
 patches:
   - patch: |-
       - op: add
-        path: /spec/template/spec/containers/1/args/-
+        path: /spec/template/spec/initContainers/0/args/-
         value: -host-opt-path=/var/lib/toolbox/zeropod
     target:
       kind: DaemonSet

config/k3s/kustomization.yaml

@@ -5,7 +5,7 @@ patchesStrategicMerge:
 patches:
   - patch: |-
       - op: add
-        path: /spec/template/spec/containers/1/args/-
+        path: /spec/template/spec/initContainers/0/args/-
         value: -runtime=k3s
     target:
       kind: DaemonSet

config/production/kustomization.yaml

@@ -10,7 +10,7 @@ images:
 patches:
   - patch: |-
       - op: add
-        path: /spec/template/spec/containers/1/args/-
+        path: /spec/template/spec/initContainers/0/args/-
         value: -criu-image=ghcr.io/ctrox/zeropod-criu:v3.19
     target:
       kind: DaemonSet

config/rke2/kustomization.yaml

@@ -5,7 +5,7 @@ patchesStrategicMerge:
 patches:
   - patch: |-
       - op: add
-        path: /spec/template/spec/containers/1/args/-
+        path: /spec/template/spec/initContainers/0/args/-
         value: -runtime=rke2
     target:
       kind: DaemonSet

config/uninstall/kustomization.yaml

@@ -1,6 +1,20 @@
 resources:
-  - uninstaller.yaml
-images:
-  - name: installer
-    newName: ghcr.io/ctrox/zeropod-installer
-    newTag: dev
+  - ../production
+patches:
+  - patch: |-
+      - op: add
+        path: /spec/template/spec/initContainers/0/args/-
+        value: -uninstall
+      - op: replace
+        path: /spec/template/spec/initContainers/0/volumeMounts/2
+        value:
+          mountPath: /opt
+          name: opt
+      - op: replace
+        path: /spec/template/spec/volumes/2
+        value:
+          hostPath:
+            path: /opt
+          name: opt
+    target:
+      kind: DaemonSet