Fix etcd snapshot reconcile for agentless nodes

pkg/cli/server/server.go

@@ -169,6 +169,7 @@ func run(app *cli.Context, cfg *cmds.Server, leaderControllers server.CustomCont
 	serverConfig.ControlConfig.DisableAPIServer = cfg.DisableAPIServer
 	serverConfig.ControlConfig.DisableScheduler = cfg.DisableScheduler
 	serverConfig.ControlConfig.DisableControllerManager = cfg.DisableControllerManager
+	serverConfig.ControlConfig.DisableAgent = cfg.DisableAgent
 	serverConfig.ControlConfig.EmbeddedRegistry = cfg.EmbeddedRegistry
 	serverConfig.ControlConfig.ClusterInit = cfg.ClusterInit
 	serverConfig.ControlConfig.EncryptSecrets = cfg.EncryptSecrets

pkg/daemons/config/types.go

@@ -181,6 +181,7 @@ type Control struct {
 	KineTLS                  bool
 	Datastore                endpoint.Config `json:"-"`
 	Disables                 map[string]bool
+	DisableAgent             bool
 	DisableAPIServer         bool
 	DisableControllerManager bool
 	DisableETCD              bool

pkg/etcd/snapshot.go

@@ -850,6 +850,12 @@ func (e *ETCD) ReconcileSnapshotData(ctx context.Context) error {
 		}
 	}
 
+	// Agentless servers do not have a node. If we are running agentless, return early to avoid pruning
+	// snapshots for nonexistent nodes and trying to patch the reconcile annotations on our node.
+	if e.config.DisableAgent {
+		return nil
+	}
+
 	// List all snapshots in Kubernetes not stored on S3 or a current etcd node.
 	// These snapshots are local to a node that no longer runs etcd and cannot be restored.
 	// If the node rejoins later and has local snapshots, it will reconcile them itself.

pkg/etcd/snapshot_controller.go

@@ -2,6 +2,7 @@ package etcd
 
 import (
 	"context"
+	"os"
 	"sort"
 	"strconv"
 	"strings"
@@ -176,6 +177,23 @@ func (e *etcdSnapshotHandler) reconcile() error {
 		return err
 	}
 
+	// If running without an agent there will not be a node for this server;
+	// create a dummy node and assume it has reconciled.
+	if e.etcd.config.DisableAgent {
+		node := v1.Node{
+			ObjectMeta: metav1.ObjectMeta{
+				Name: os.Getenv("NODE_NAME"),
+				Annotations: map[string]string{
+					annotationLocalReconciled: "true",
+				},
+			},
+		}
+		if e.etcd.s3 != nil {
+			node.Annotations[annotationS3Reconciled] = "true"
+		}
+		nodeList.Items = append(nodeList.Items, node)
+	}
+
 	// Once a node has set the reconcile annotation, it is considered to have
 	// migrated to using ETCDSnapshotFile resources, and any old configmap
 	// entries for it can be pruned. Until the annotation is set, we will leave