If no etcd was deployed, fail etcd-snapshot with a useful error

pkg/cluster/managed.go

@@ -11,9 +11,13 @@ import (
 	"os"
 	"time"
 
+	"github.com/pkg/errors"
+
+	"github.com/gorilla/mux"
 	"github.com/k3s-io/k3s/pkg/cluster/managed"
 	"github.com/k3s-io/k3s/pkg/etcd"
 	"github.com/k3s-io/k3s/pkg/nodepassword"
+	"github.com/k3s-io/k3s/pkg/util"
 	"github.com/k3s-io/k3s/pkg/version"
 	"github.com/sirupsen/logrus"
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
@@ -96,7 +100,7 @@ func (c *Cluster) start(ctx context.Context) error {
 // management of etcd cluster membership without being disrupted when a member is removed from the cluster.
 func (c *Cluster) registerDBHandlers(handler http.Handler) (http.Handler, error) {
 	if c.managedDB == nil {
-		return handler, nil
+		return handlerNoEtcd(handler), nil
 	}
 
 	return c.managedDB.Register(handler)
@@ -168,3 +172,18 @@ func (c *Cluster) deleteNodePasswdSecret(ctx context.Context) {
 		logrus.Warnf("failed to delete old node password secret: %v", err)
 	}
 }
+
+// handlerNoEtcd wraps a handler with an error message indicating that etcd is not deployed.
+func handlerNoEtcd(handler http.Handler) http.Handler {
+	r := mux.NewRouter().SkipClean(true)
+
+	// Wildcard route for anything after /db/
+	r.HandleFunc("/db/{_:.*}", func(resp http.ResponseWriter, r *http.Request) {
+		util.SendError(errors.New("etcd datastore disabled"), resp, r, http.StatusBadRequest)
+	})
+
+	// Needs to come at the end, otherwise wildcard routes won't work
+	r.NotFoundHandler = handler
+
+	return r
+}

tests/e2e/snapshotrestore/snapshotrestore_test.go

@@ -145,17 +145,6 @@ var _ = Describe("Verify snapshots and cluster restores work", Ordered, func() {
 			Expect(e2e.RunCmdOnNode(cmd, serverNodeNames[0])).Error().NotTo(HaveOccurred())
 		})
 
-		It("Resets non bootstrap nodes", func() {
-			for _, nodeName := range serverNodeNames {
-				if nodeName != serverNodeNames[0] {
-					cmd := "k3s server --cluster-reset"
-					response, err := e2e.RunCmdOnNode(cmd, nodeName)
-					Expect(err).NotTo(HaveOccurred())
-					Expect(response).Should(ContainSubstring("Managed etcd cluster membership has been reset, restart without --cluster-reset flag now"))
-				}
-			}
-		})
-
 		It("Checks that other servers are not ready", func() {
 			fmt.Printf("\nFetching node status\n")
 			Eventually(func(g Gomega) {