[#1349] node: Evacuate objects without setting mode to MAINTENANCE

Signed-off-by: Anton Nikiforov <an.nikiforov@yadro.com>

cmd/frostfs-cli/modules/control/shards_list.go

@@ -72,6 +72,7 @@ func prettyPrintShardsJSON(cmd *cobra.Command, ii []control.ShardInfo) {
 			"writecache":             i.GetWritecachePath(),
 			"pilorama":               i.GetPiloramaPath(),
 			"error_count":            i.GetErrorCount(),
+			"evacuation_in_progress": i.GetEvacuationInProgress(),
 		})
 	}
 
@@ -105,7 +106,8 @@ func prettyPrintShards(cmd *cobra.Command, ii []control.ShardInfo) {
 			sb.String()+
 			pathPrinter("Write-cache", i.GetWritecachePath())+
 			pathPrinter("Pilorama", i.GetPiloramaPath())+
-			fmt.Sprintf("Error count: %d\n", i.GetErrorCount()),
+			fmt.Sprintf("Error count: %d\n", i.GetErrorCount())+
+			fmt.Sprintf("Evacuation in progress: %t\n", i.GetEvacuationInProgress()),
 			base58.Encode(i.GetShard_ID()),
 			shardModeToString(i.GetMode()),
 		)

docs/evacuation.md

@@ -10,6 +10,12 @@ First of all, by the evacuation the data is transferred to other shards of the s
 
 Only one running evacuation process is allowed on the node at a time.
 
+It is not necessary to turn maintenance mode on storage node.
+
+Once evacuation from shard started, it is impossible to read data from it via public API, except the case when evacuation stopped manually or node restarted.
+
+Because it is necessary to prevent removing by policer objects with policy `REP 1 ...` from remote node during evacuation.
+
 `frostfs-cli` utility is used to manage evacuation.
 
 ## Commands

internal/metrics/engine.go

@@ -27,6 +27,7 @@ type EngineMetrics interface {
 	IncRefillObjectsCount(shardID, path string, size int, success bool)
 	SetRefillPercent(shardID, path string, percent uint32)
 	SetRefillStatus(shardID, path, status string)
+	SetEvacuationInProgress(shardID string, value bool)
 
 	WriteCache() WriteCacheMetrics
 	GC() GCMetrics
@@ -45,6 +46,7 @@ type engineMetrics struct {
 	refillObjCounter     *prometheus.GaugeVec
 	refillPayloadCounter *prometheus.GaugeVec
 	refillPercentCounter *prometheus.GaugeVec
+	evacuationInProgress *shardIDModeValue
 
 	gc         *gcMetrics
 	writeCache *writeCacheMetrics
@@ -72,6 +74,7 @@ func newEngineMetrics() *engineMetrics {
 		refillObjCounter:     newEngineGaugeVector("resync_metabase_objects_total", "Count of objects resynced from blobstore to metabase", []string{shardIDLabel, pathLabel, successLabel}),
 		refillPayloadCounter: newEngineGaugeVector("resync_metabase_objects_size_bytes", "Size of objects resynced from blobstore to metabase", []string{shardIDLabel, pathLabel, successLabel}),
 		refillPercentCounter: newEngineGaugeVector("resync_metabase_complete_percent", "Percent of resynced from blobstore to metabase completeness", []string{shardIDLabel, pathLabel}),
+		evacuationInProgress: newShardIDMode(engineSubsystem, "evacuation_in_progress", "Shard evacuation in progress"),
 	}
 }
 
@@ -124,6 +127,7 @@ func (m *engineMetrics) DeleteShardMetrics(shardID string) {
 	m.refillPercentCounter.DeletePartialMatch(prometheus.Labels{shardIDLabel: shardID})
 	m.mode.Delete(shardID)
 	m.refillStatus.DeleteByShardID(shardID)
+	m.evacuationInProgress.Delete(shardID)
 }
 
 func (m *engineMetrics) AddToObjectCounter(shardID, objectType string, delta int) {
@@ -213,3 +217,7 @@ func (m *engineMetrics) SetRefillPercent(shardID, path string, percent uint32) {
 func (m *engineMetrics) SetRefillStatus(shardID, path, status string) {
 	m.refillStatus.SetMode(shardID, path, status)
 }
+
+func (m *engineMetrics) SetEvacuationInProgress(shardID string, value bool) {
+	m.evacuationInProgress.SetMode(shardID, strconv.FormatBool(value))
+}

pkg/local_object_storage/engine/evacuate.go

@@ -366,6 +366,7 @@ func (e *StorageEngine) evacuateShardObjects(ctx context.Context, shardID string
 	listPrm.WithCount(defaultEvacuateBatchSize)
 
 	sh := shardsToEvacuate[shardID]
+	sh.SetEvacuationInProgress(true)
 
 	var c *meta.Cursor
 	for {
@@ -655,6 +656,7 @@ func (e *StorageEngine) evacuateObjects(ctx context.Context, sh *shard.Shard, to
 
 		var getPrm shard.GetPrm
 		getPrm.SetAddress(addr)
+		getPrm.SkipEvacCheck(true)
 
 		getRes, err := sh.Get(ctx, getPrm)
 		if err != nil {
@@ -765,3 +767,11 @@ func (e *StorageEngine) ResetEvacuationStatus(ctx context.Context) error {
 
 	return e.evacuateLimiter.ResetEvacuationStatus()
 }
+
+func (e *StorageEngine) ResetEvacuationStatusForShards() {
+	e.mtx.RLock()
+	defer e.mtx.RUnlock()
+	for _, sh := range e.shards {
+		sh.SetEvacuationInProgress(false)
+	}
+}

pkg/local_object_storage/engine/evacuate_test.go

@@ -125,6 +125,34 @@ func TestEvacuateShardObjects(t *testing.T) {
 	// Second case ensures that all objects are indeed moved and available.
 	checkHasObjects(t)
 
+	// Objects on evacuated shards should be logically unavailable, but persisted on disk.
+	// This is necessary to prevent removing it by policer in case of `REP 1` policy.
+	for _, obj := range objects[len(objects)-objPerShard:] {
+		var prmGet shard.GetPrm
+		prmGet.SetAddress(objectCore.AddressOf(obj))
+		_, err = e.shards[evacuateShardID].Get(context.Background(), prmGet)
+		require.Error(t, err)
+
+		prmGet.SkipEvacCheck(true)
+		_, err = e.shards[evacuateShardID].Get(context.Background(), prmGet)
+		require.NoError(t, err)
+
+		var prmHead shard.HeadPrm
+		prmHead.SetAddress(objectCore.AddressOf(obj))
+		_, err = e.shards[evacuateShardID].Head(context.Background(), prmHead)
+		require.Error(t, err)
+
+		var existsPrm shard.ExistsPrm
+		existsPrm.Address = objectCore.AddressOf(obj)
+		_, err = e.shards[evacuateShardID].Exists(context.Background(), existsPrm)
+		require.Error(t, err)
+
+		var rngPrm shard.RngPrm
+		rngPrm.SetAddress(objectCore.AddressOf(obj))
+		_, err = e.shards[evacuateShardID].GetRange(context.Background(), rngPrm)
+		require.Error(t, err)
+	}
+
 	// Calling it again is OK, but all objects are already moved, so no new PUTs should be done.
 	res, err = e.Evacuate(context.Background(), prm)
 	require.NoError(t, err)

pkg/local_object_storage/engine/metrics.go

@@ -30,6 +30,7 @@ type MetricRegister interface {
 	IncRefillObjectsCount(shardID, path string, size int, success bool)
 	SetRefillPercent(shardID, path string, percent uint32)
 	SetRefillStatus(shardID, path, status string)
+	SetEvacuationInProgress(shardID string, value bool)
 
 	WriteCache() metrics.WriteCacheMetrics
 	GC() metrics.GCMetrics

pkg/local_object_storage/engine/shards.go

@@ -97,6 +97,10 @@ func (m *metricsWithID) SetRefillStatus(path string, status string) {
 	m.mw.SetRefillStatus(m.id, path, status)
 }
 
+func (m *metricsWithID) SetEvacuationInProgress(value bool) {
+	m.mw.SetEvacuationInProgress(m.id, value)
+}
+
 // AddShard adds a new shard to the storage engine.
 //
 // Returns any error encountered that did not allow adding a shard.

pkg/local_object_storage/shard/exists.go

@@ -5,7 +5,9 @@ import (
 
 	"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/local_object_storage/blobstor/common"
 	meta "git.frostfs.info/TrueCloudLab/frostfs-node/pkg/local_object_storage/metabase"
+	"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/local_object_storage/util/logicerr"
 	"git.frostfs.info/TrueCloudLab/frostfs-observability/tracing"
+	apistatus "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/client/status"
 	oid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object/id"
 	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/trace"
@@ -60,6 +62,8 @@ func (s *Shard) Exists(ctx context.Context, prm ExistsPrm) (ExistsRes, error) {
 
 	if s.info.Mode.Disabled() {
 		return ExistsRes{}, ErrShardDisabled
+	} else if s.info.EvacuationInProgress {
+		return ExistsRes{}, logicerr.Wrap(new(apistatus.ObjectNotFound))
 	} else if s.info.Mode.NoMetabase() {
 		var p common.ExistsPrm
 		p.Address = prm.Address

pkg/local_object_storage/shard/get.go

@@ -29,6 +29,7 @@ type storFetcher = func(stor *blobstor.BlobStor, id []byte) (*objectSDK.Object,
 type GetPrm struct {
 	addr          oid.Address
 	skipMeta      bool
+	skipEvacCheck bool
 }
 
 // GetRes groups the resulting values of Get operation.
@@ -50,6 +51,11 @@ func (p *GetPrm) SetIgnoreMeta(ignore bool) {
 	p.skipMeta = ignore
 }
 
+// SkipEvacCheck is a Get option which instruct to skip check is evacuation in progress.
+func (p *GetPrm) SkipEvacCheck(val bool) {
+	p.skipEvacCheck = val
+}
+
 // Object returns the requested object.
 func (r GetRes) Object() *objectSDK.Object {
 	return r.obj
@@ -85,6 +91,10 @@ func (s *Shard) Get(ctx context.Context, prm GetPrm) (GetRes, error) {
 		return GetRes{}, ErrShardDisabled
 	}
 
+	if s.info.EvacuationInProgress && !prm.skipEvacCheck {
+		return GetRes{}, logicerr.Wrap(new(apistatus.ObjectNotFound))
+	}
+
 	cb := func(stor *blobstor.BlobStor, id []byte) (*objectSDK.Object, error) {
 		var getPrm common.GetPrm
 		getPrm.Address = prm.addr

pkg/local_object_storage/shard/head.go

@@ -4,7 +4,9 @@ import (
 	"context"
 
 	meta "git.frostfs.info/TrueCloudLab/frostfs-node/pkg/local_object_storage/metabase"
+	"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/local_object_storage/util/logicerr"
 	"git.frostfs.info/TrueCloudLab/frostfs-observability/tracing"
+	apistatus "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/client/status"
 	objectSDK "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object"
 	oid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object/id"
 	"go.opentelemetry.io/otel/attribute"
@@ -70,6 +72,11 @@ func (s *Shard) Head(ctx context.Context, prm HeadPrm) (HeadRes, error) {
 		res, err = s.Get(ctx, getPrm)
 		obj = res.Object()
 	} else {
+		s.m.RLock()
+		defer s.m.RUnlock()
+		if s.info.EvacuationInProgress {
+			return HeadRes{}, logicerr.Wrap(new(apistatus.ObjectNotFound))
+		}
 		var headParams meta.GetPrm
 		headParams.SetAddress(prm.addr)
 		headParams.SetRaw(prm.raw)

pkg/local_object_storage/shard/info.go

@@ -16,6 +16,9 @@ type Info struct {
 	// Shard mode.
 	Mode mode.Mode
 
+	// True when evacuation is in progress.
+	EvacuationInProgress bool
+
 	// Information about the metabase.
 	MetaBaseInfo meta.Info
 

pkg/local_object_storage/shard/metrics_test.go

@@ -192,6 +192,9 @@ func (m *metricsStore) SetRefillStatus(_ string, status string) {
 	m.refillStatus = status
 }
 
+func (m *metricsStore) SetEvacuationInProgress(bool) {
+}
+
 func TestCounters(t *testing.T) {
 	t.Parallel()
 

pkg/local_object_storage/shard/range.go

@@ -87,6 +87,10 @@ func (s *Shard) GetRange(ctx context.Context, prm RngPrm) (RngRes, error) {
 	s.m.RLock()
 	defer s.m.RUnlock()
 
+	if s.info.EvacuationInProgress {
+		return RngRes{}, logicerr.Wrap(new(apistatus.ObjectNotFound))
+	}
+
 	if s.info.Mode.Disabled() {
 		return RngRes{}, ErrShardDisabled
 	}

pkg/local_object_storage/shard/shard.go

@@ -97,6 +97,8 @@ type MetricsWriter interface {
 	SetRefillPercent(path string, percent uint32)
 	// SetRefillStatus sets refill status.
 	SetRefillStatus(path string, status string)
+	// SetEvacuationInProgress sets evacuation status
+	SetEvacuationInProgress(value bool)
 }
 
 type cfg struct {
@@ -579,3 +581,12 @@ func (s *Shard) DeleteShardMetrics() {
 		s.cfg.metricsWriter.DeleteShardMetrics()
 	}
 }
+
+func (s *Shard) SetEvacuationInProgress(val bool) {
+	s.m.Lock()
+	defer s.m.Unlock()
+	s.info.EvacuationInProgress = val
+	if s.metricsWriter != nil {
+		s.metricsWriter.SetEvacuationInProgress(val)
+	}
+}

pkg/services/control/server/evacuate_async.go

@@ -101,6 +101,9 @@ func (s *Server) StopShardEvacuation(ctx context.Context, req *control.StopShard
 	if err != nil {
 		return nil, status.Error(codes.Internal, err.Error())
 	}
+
+	s.s.ResetEvacuationStatusForShards()
+
 	return resp, nil
 }
 

pkg/services/control/server/list_shards.go

@@ -53,6 +53,7 @@ func (s *Server) ListShards(_ context.Context, req *control.ListShardsRequest) (
 
 		si.SetMode(m)
 		si.SetErrorCount(sh.ErrorCount)
+		si.SetEvacuationInProgress(sh.EvacuationInProgress)
 
 		shardInfos = append(shardInfos, *si)
 	}

pkg/services/control/types.proto

@@ -142,6 +142,9 @@ message ShardInfo {
 
   // Path to shard's pilorama storage.
   string pilorama_path = 7 [ json_name = "piloramaPath" ];
+
+  // Evacuation status.
+  bool evacuation_in_progress = 8 [ json_name = "evacuationInProgress" ];
 }
 
 // Blobstor component description.