Prevent ingesting samples older than past_grace_period (#8262)

* Prevent ingesting samples older than past_grace_period

This PR implements a new limit, similar to `creation_grace_period`, that
limits the age of the ingested samples based on the wall clock.

It also takes into account the OOO window, to avoid having to change
both settings when OOO window is modified.

The default value of 1 week should cover any observability needs. If
some customer wants to backfill their samples in order, they can
increase the value of that to `100y` in the config to cover 100 years,
for example.

Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>

* Update CHANGELOG.md

Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>

* Fix test

Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>

* make doc

Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>

* Fix TestOwnedSeriesPartitionsTestUserShuffleSharding

Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>

* Fix TestOwnedSeriesServiceWithIngesterRing

Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>

* More test fixes

Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>

* Revert to "0 means disabled"

Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>

* make docs reference-help

Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>

* Add runbooks

Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>

* make doc

Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>

* Update docs/sources/mimir/manage/mimir-runbooks/_index.md

Co-authored-by: Jack Baldry <jack.baldry@grafana.com>

* Update docs/sources/mimir/manage/mimir-runbooks/_index.md

---------

Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
Co-authored-by: Jack Baldry <jack.baldry@grafana.com>

CHANGELOG.md

@@ -25,6 +25,7 @@
 * [FEATURE] Query-frontend, querier: new experimental `/cardinality/active_native_histogram_metrics` API to get active native histogram metric names with statistics about active native histogram buckets. #7982 #7986 #8008
 * [FEATURE] Alertmanager: Added `-alertmanager.max-silences-count` and `-alertmanager.max-silence-size-bytes` to set limits on per tenant silences. Disabled by default. #6898
 * [FEATURE] Ingester: add experimental support for the server-side circuit breakers when writing to ingesters. This can be enabled using `-ingester.circuit-breaker.enabled` option. Further `-ingester.circuit-breaker.*` options for configuring circuit-breaker are available. Added metrics `cortex_ingester_circuit_breaker_results_total`,  `cortex_ingester_circuit_breaker_transitions_total` and `cortex_ingester_circuit_breaker_current_state`. #8180
+* [FEATURE] Distributor, ingester: add new setting `-validation.past-grace-period` to limit how old (based on the wall clock minus OOO window) the ingested samples can be. The default 0 value disables this limit. #8262
 * [ENHANCEMENT] Reduced memory allocations in functions used to propagate contextual information between gRPC calls. #7529
 * [ENHANCEMENT] Distributor: add experimental limit for exemplars per series per request, enabled with `-distributor.max-exemplars-per-series-per-request`, the number of discarded exemplars are tracked with `cortex_discarded_exemplars_total{reason="too_many_exemplars_per_series_per_request"}` #7989 #8010
 * [ENHANCEMENT] Store-gateway: merge series from different blocks concurrently. #7456

cmd/mimir/config-descriptor.json

@@ -3436,13 +3436,24 @@
           "kind": "field",
           "name": "creation_grace_period",
           "required": false,
-          "desc": "Controls how far into the future incoming samples and exemplars are accepted compared to the wall clock. Any sample or exemplar will be rejected if its timestamp is greater than '(now + grace_period)'. This configuration is enforced in the distributor and ingester.",
+          "desc": "Controls how far into the future incoming samples and exemplars are accepted compared to the wall clock. Any sample or exemplar will be rejected if its timestamp is greater than '(now + creation_grace_period)'. This configuration is enforced in the distributor and ingester.",
           "fieldValue": null,
           "fieldDefaultValue": 600000000000,
           "fieldFlag": "validation.create-grace-period",
           "fieldType": "duration",
           "fieldCategory": "advanced"
         },
+        {
+          "kind": "field",
+          "name": "past_grace_period",
+          "required": false,
+          "desc": "Controls how far into the past incoming samples and exemplars are accepted compared to the wall clock. Any sample or exemplar will be rejected if its timestamp is lower than '(now - OOO window - past_grace_period)'. This configuration is enforced in the distributor and ingester. 0 to disable.",
+          "fieldValue": null,
+          "fieldDefaultValue": 0,
+          "fieldFlag": "validation.past-grace-period",
+          "fieldType": "duration",
+          "fieldCategory": "advanced"
+        },
         {
           "kind": "field",
           "name": "enforce_metadata_metric_name",

cmd/mimir/help-all.txt.tmpl

@@ -2876,7 +2876,7 @@ Usage of ./cmd/mimir/mimir:
   -usage-stats.installation-mode string
     	Installation mode. Supported values: custom, helm, jsonnet. (default "custom")
   -validation.create-grace-period duration
-    	Controls how far into the future incoming samples and exemplars are accepted compared to the wall clock. Any sample or exemplar will be rejected if its timestamp is greater than '(now + grace_period)'. This configuration is enforced in the distributor and ingester. (default 10m)
+    	Controls how far into the future incoming samples and exemplars are accepted compared to the wall clock. Any sample or exemplar will be rejected if its timestamp is greater than '(now + creation_grace_period)'. This configuration is enforced in the distributor and ingester. (default 10m)
   -validation.enforce-metadata-metric-name
     	Enforce every metadata has a metric name. (default true)
   -validation.max-label-names-per-series int
@@ -2889,6 +2889,8 @@ Usage of ./cmd/mimir/mimir:
     	Maximum length accepted for metric metadata. Metadata refers to Metric Name, HELP and UNIT. Longer metadata is dropped except for HELP which is truncated. (default 1024)
   -validation.max-native-histogram-buckets int
     	Maximum number of buckets per native histogram sample. 0 to disable the limit.
+  -validation.past-grace-period duration
+    	Controls how far into the past incoming samples and exemplars are accepted compared to the wall clock. Any sample or exemplar will be rejected if its timestamp is lower than '(now - OOO window - past_grace_period)'. This configuration is enforced in the distributor and ingester. 0 to disable.
   -validation.reduce-native-histogram-over-max-buckets
     	Whether to reduce or reject native histogram samples with more buckets than the configured limit. (default true)
   -validation.separate-metrics-group-label string

docs/sources/mimir/configure/configuration-parameters/index.md

@@ -3073,11 +3073,18 @@ The `limits` block configures default and per-tenant limits imposed by component
 
 # (advanced) Controls how far into the future incoming samples and exemplars are
 # accepted compared to the wall clock. Any sample or exemplar will be rejected
-# if its timestamp is greater than '(now + grace_period)'. This configuration is
-# enforced in the distributor and ingester.
+# if its timestamp is greater than '(now + creation_grace_period)'. This
+# configuration is enforced in the distributor and ingester.
 # CLI flag: -validation.create-grace-period
 [creation_grace_period: <duration> | default = 10m]
 
+# (advanced) Controls how far into the past incoming samples and exemplars are
+# accepted compared to the wall clock. Any sample or exemplar will be rejected
+# if its timestamp is lower than '(now - OOO window - past_grace_period)'. This
+# configuration is enforced in the distributor and ingester. 0 to disable.
+# CLI flag: -validation.past-grace-period
+[past_grace_period: <duration> | default = 0s]
+
 # (advanced) Enforce every metadata has a metric name.
 # CLI flag: -validation.enforce-metadata-metric-name
 [enforce_metadata_metric_name: <boolean> | default = true]

docs/sources/mimir/manage/mimir-runbooks/_index.md

@@ -1698,6 +1698,31 @@ On a per-tenant basis, you can fine tune the tolerance by configuring the `creat
 Only series with invalid samples are skipped during the ingestion. Valid samples within the same request are still ingested.
 {{< /admonition >}}
 
+### err-mimir-too-far-in-past
+
+This non-critical error occurs when Mimir rejects a sample because its timestamp is too far in the past compared to the wall clock.
+
+How it **works**:
+
+- The distributor or the ingester implements an lower limit on the timestamp of incoming samples, it is used to protect the system from potential abuse or mistakes.
+- The lower limit is defined by the current wall clock minus the `out_of_order_time_window` and minus the `past_grace_period` settings.
+- The samples that are too far in the past aren't ingested.
+
+How to **fix** it:
+
+- Make sure that it is intended that the timestamps of the incoming samples are that old.
+- If the timestamps are correct, increase the `past_grace_period` setting, or set it to 0 to disable the limit.
+
+{{< admonition type="note" >}}
+Only the invalid samples are skipped during the ingestion. Valid samples within the same request are still ingested.
+{{< /admonition >}}
+
+### err-mimir-exemplar-too-far-in-past
+
+This non-critical error occurs when Mimir rejects an exemplar because its timestamp is too far in the past compared to the wall clock.
+
+Refer to [`err-mimir-too-far-in-past`](#err-mimir-too-far-in-past) for more details and how to fix it.
+
 ### err-mimir-exemplar-labels-missing
 
 This non-critical error occurs when Mimir receives a write request that contains an exemplar without a label that identifies the related metric.

pkg/distributor/distributor.go

@@ -1020,6 +1020,10 @@ func (d *Distributor) prePushValidationMiddleware(next PushFunc) PushFunc {
 		var minExemplarTS int64
 		if earliestSampleTimestampMs != math.MaxInt64 {
 			minExemplarTS = earliestSampleTimestampMs - 5*time.Minute.Milliseconds()
+
+			if d.limits.PastGracePeriod(userID) > 0 {
+				minExemplarTS = max(minExemplarTS, now.Add(-d.limits.PastGracePeriod(userID)).Add(-d.limits.OutOfOrderTimeWindow(userID)).UnixMilli())
+			}
 		}
 
 		// Enforce the creation grace period on exemplars too.

pkg/distributor/distributor_test.go

@@ -6762,6 +6762,7 @@ func TestDistributorValidation(t *testing.T) {
 		labels      [][]mimirpb.LabelAdapter
 		samples     []mimirpb.Sample
 		exemplars   []*mimirpb.Exemplar
+		limits      func(limits *validation.Limits)
 		expectedErr *status.Status
 	}{
 		"validation passes": {
@@ -6799,6 +6800,18 @@ func TestDistributorValidation(t *testing.T) {
 			expectedErr: status.New(codes.FailedPrecondition, fmt.Sprintf(sampleTimestampTooNewMsgFormat, future, "testmetric")),
 		},
 
+		"validation does not fail for samples from the past without past_grace_period setting": {
+			labels:  [][]mimirpb.LabelAdapter{{{Name: "foo", Value: "bar"}, {Name: labels.MetricName, Value: "testmetric"}}},
+			samples: []mimirpb.Sample{{TimestampMs: int64(past), Value: 1}},
+		},
+
+		"validation fails for samples from the past": {
+			labels:      [][]mimirpb.LabelAdapter{{{Name: labels.MetricName, Value: "testmetric"}, {Name: "foo", Value: "bar"}}},
+			samples:     []mimirpb.Sample{{TimestampMs: int64(past), Value: 4}},
+			limits:      func(limits *validation.Limits) { limits.PastGracePeriod = model.Duration(now.Sub(past) / 2) },
+			expectedErr: status.New(codes.FailedPrecondition, fmt.Sprintf(sampleTimestampTooOldMsgFormat, past, "testmetric")),
+		},
+
 		"exceeds maximum labels per series": {
 			labels: [][]mimirpb.LabelAdapter{{{Name: labels.MetricName, Value: "testmetric"}, {Name: "foo", Value: "bar"}, {Name: "foo2", Value: "bar2"}}},
 			samples: []mimirpb.Sample{{
@@ -6875,6 +6888,9 @@ func TestDistributorValidation(t *testing.T) {
 			limits.CreationGracePeriod = model.Duration(2 * time.Hour)
 			limits.MaxLabelNamesPerSeries = 2
 			limits.MaxGlobalExemplarsPerUser = 10
+			if tc.limits != nil {
+				tc.limits(&limits)
+			}
 
 			ds, _, _, _ := prepare(t, prepConfig{
 				numIngesters:    3,

pkg/distributor/validate.go

@@ -40,6 +40,7 @@ var (
 	reasonInvalidNativeHistogramSchema = globalerror.InvalidSchemaNativeHistogram.LabelValue()
 	reasonDuplicateLabelNames          = globalerror.SeriesWithDuplicateLabelNames.LabelValue()
 	reasonTooFarInFuture               = globalerror.SampleTooFarInFuture.LabelValue()
+	reasonTooFarInPast                 = globalerror.SampleTooFarInPast.LabelValue()
 
 	// Discarded exemplars reasons.
 	reasonExemplarLabelsMissing               = globalerror.ExemplarLabelsMissing.LabelValue()
@@ -84,6 +85,10 @@ var (
 		"received a sample whose timestamp is too far in the future, timestamp: %d series: '%.200s'",
 		validation.CreationGracePeriodFlag,
 	)
+	sampleTimestampTooOldMsgFormat = globalerror.SampleTooFarInPast.MessageWithPerTenantLimitConfig(
+		"received a sample whose timestamp is too far in the past, timestamp: %d series: '%.200s'",
+		validation.PastGracePeriodFlag,
+	)
 	exemplarEmptyLabelsMsgFormat = globalerror.ExemplarLabelsMissing.Message(
 		"received an exemplar with no valid labels, timestamp: %d series: %s labels: %s",
 	)
@@ -108,8 +113,10 @@ var (
 // sampleValidationConfig helps with getting required config to validate sample.
 type sampleValidationConfig interface {
 	CreationGracePeriod(userID string) time.Duration
+	PastGracePeriod(userID string) time.Duration
 	MaxNativeHistogramBuckets(userID string) int
 	ReduceNativeHistogramOverMaxBuckets(userID string) bool
+	OutOfOrderTimeWindow(userID string) time.Duration
 }
 
 // sampleValidationMetrics is a collection of metrics used during sample validation.
@@ -124,6 +131,7 @@ type sampleValidationMetrics struct {
 	invalidNativeHistogramSchema *prometheus.CounterVec
 	duplicateLabelNames          *prometheus.CounterVec
 	tooFarInFuture               *prometheus.CounterVec
+	tooFarInPast                 *prometheus.CounterVec
 }
 
 func (m *sampleValidationMetrics) deleteUserMetrics(userID string) {
@@ -138,6 +146,7 @@ func (m *sampleValidationMetrics) deleteUserMetrics(userID string) {
 	m.invalidNativeHistogramSchema.DeletePartialMatch(filter)
 	m.duplicateLabelNames.DeletePartialMatch(filter)
 	m.tooFarInFuture.DeletePartialMatch(filter)
+	m.tooFarInPast.DeletePartialMatch(filter)
 }
 
 func (m *sampleValidationMetrics) deleteUserMetricsForGroup(userID, group string) {
@@ -151,6 +160,7 @@ func (m *sampleValidationMetrics) deleteUserMetricsForGroup(userID, group string
 	m.invalidNativeHistogramSchema.DeleteLabelValues(userID, group)
 	m.duplicateLabelNames.DeleteLabelValues(userID, group)
 	m.tooFarInFuture.DeleteLabelValues(userID, group)
+	m.tooFarInPast.DeleteLabelValues(userID, group)
 }
 
 func newSampleValidationMetrics(r prometheus.Registerer) *sampleValidationMetrics {
@@ -165,6 +175,7 @@ func newSampleValidationMetrics(r prometheus.Registerer) *sampleValidationMetric
 		invalidNativeHistogramSchema: validation.DiscardedSamplesCounter(r, reasonInvalidNativeHistogramSchema),
 		duplicateLabelNames:          validation.DiscardedSamplesCounter(r, reasonDuplicateLabelNames),
 		tooFarInFuture:               validation.DiscardedSamplesCounter(r, reasonTooFarInFuture),
+		tooFarInPast:                 validation.DiscardedSamplesCounter(r, reasonTooFarInPast),
 	}
 }
 
@@ -211,6 +222,12 @@ func validateSample(m *sampleValidationMetrics, now model.Time, cfg sampleValida
 		return fmt.Errorf(sampleTimestampTooNewMsgFormat, s.TimestampMs, unsafeMetricName)
 	}
 
+	if cfg.PastGracePeriod(userID) > 0 && model.Time(s.TimestampMs) < now.Add(-cfg.PastGracePeriod(userID)).Add(-cfg.OutOfOrderTimeWindow(userID)) {
+		m.tooFarInPast.WithLabelValues(userID, group).Inc()
+		unsafeMetricName, _ := extract.UnsafeMetricNameFromLabelAdapters(ls)
+		return fmt.Errorf(sampleTimestampTooOldMsgFormat, s.TimestampMs, unsafeMetricName)
+	}
+
 	return nil
 }
 
@@ -224,6 +241,12 @@ func validateSampleHistogram(m *sampleValidationMetrics, now model.Time, cfg sam
 		return false, fmt.Errorf(sampleTimestampTooNewMsgFormat, s.Timestamp, unsafeMetricName)
 	}
 
+	if cfg.PastGracePeriod(userID) > 0 && model.Time(s.Timestamp) < now.Add(-cfg.PastGracePeriod(userID)).Add(-cfg.OutOfOrderTimeWindow(userID)) {
+		m.tooFarInPast.WithLabelValues(userID, group).Inc()
+		unsafeMetricName, _ := extract.UnsafeMetricNameFromLabelAdapters(ls)
+		return false, fmt.Errorf(sampleTimestampTooOldMsgFormat, s.Timestamp, unsafeMetricName)
+	}
+
 	if s.Schema < mimirpb.MinimumHistogramSchema || s.Schema > mimirpb.MaximumHistogramSchema {
 		m.invalidNativeHistogramSchema.WithLabelValues(userID, group).Inc()
 		return false, fmt.Errorf(invalidSchemaNativeHistogramMsgFormat, s.Schema)

pkg/distributor/validate_test.go

@@ -398,6 +398,14 @@ func (c sampleValidationCfg) CreationGracePeriod(_ string) time.Duration {
 	return 0
 }
 
+func (c sampleValidationCfg) PastGracePeriod(_ string) time.Duration {
+	return 0
+}
+
+func (c sampleValidationCfg) OutOfOrderTimeWindow(_ string) time.Duration {
+	return 0
+}
+
 func (c sampleValidationCfg) MaxNativeHistogramBuckets(_ string) int {
 	return c.maxNativeHistogramBuckets
 }

pkg/frontend/querymiddleware/limits.go

@@ -75,10 +75,6 @@ type Limits interface {
 	// OutOfOrderTimeWindow returns the out-of-order time window for the user.
 	OutOfOrderTimeWindow(userID string) time.Duration
 
-	// CreationGracePeriod returns the time interval to control how far into the future
-	// incoming samples are accepted compared to the wall clock.
-	CreationGracePeriod(userID string) time.Duration
-
 	// NativeHistogramsIngestionEnabled returns whether to ingest native histograms in the ingester
 	NativeHistogramsIngestionEnabled(userID string) bool
 

pkg/ingester/errors.go

@@ -195,6 +195,9 @@ func newExemplarMissingSeriesError(timestamp model.Time, seriesLabels, exemplarL
 func newExemplarTimestampTooFarInFutureError(timestamp model.Time, seriesLabels, exemplarLabels []mimirpb.LabelAdapter) exemplarError {
 	return newExemplarError(globalerror.ExemplarTooFarInFuture, "received an exemplar whose timestamp is too far in the future", timestamp, seriesLabels, exemplarLabels)
 }
+func newExemplarTimestampTooFarInPastError(timestamp model.Time, seriesLabels, exemplarLabels []mimirpb.LabelAdapter) exemplarError {
+	return newExemplarError(globalerror.ExemplarTooFarInPast, "received an exemplar whose timestamp is too far in the past", timestamp, seriesLabels, exemplarLabels)
+}
 
 // tsdbIngestExemplarErr is an ingesterError indicating a problem with an exemplar.
 type tsdbIngestExemplarErr struct {

pkg/ingester/ingester.go

@@ -1391,7 +1391,11 @@ func (i *Ingester) pushSamplesToAppender(userID string, timeseries []mimirpb.Pre
 	var (
 		nativeHistogramsIngestionEnabled = i.limits.NativeHistogramsIngestionEnabled(userID)
 		maxTimestampMs                   = startAppend.Add(i.limits.CreationGracePeriod(userID)).UnixMilli()
+		minTimestampMs                   = int64(math.MinInt64)
 	)
+	if i.limits.PastGracePeriod(userID) > 0 {
+		minTimestampMs = startAppend.Add(-i.limits.PastGracePeriod(userID)).Add(-i.limits.OutOfOrderTimeWindow(userID)).UnixMilli()
+	}
 
 	var builder labels.ScratchBuilder
 	var nonCopiedLabels labels.Labels
@@ -1459,6 +1463,9 @@ func (i *Ingester) pushSamplesToAppender(userID string, timeseries []mimirpb.Pre
 			if s.TimestampMs > maxTimestampMs {
 				handleAppendError(globalerror.SampleTooFarInFuture, s.TimestampMs, ts.Labels)
 				continue
+			} else if s.TimestampMs < minTimestampMs {
+				handleAppendError(globalerror.SampleTooFarInPast, s.TimestampMs, ts.Labels)
+				continue
 			}
 
 			// If the cached reference exists, we try to use it.
@@ -1499,6 +1506,9 @@ func (i *Ingester) pushSamplesToAppender(userID string, timeseries []mimirpb.Pre
 				if h.Timestamp > maxTimestampMs {
 					handleAppendError(globalerror.SampleTooFarInFuture, h.Timestamp, ts.Labels)
 					continue
+				} else if h.Timestamp < minTimestampMs {
+					handleAppendError(globalerror.SampleTooFarInPast, h.Timestamp, ts.Labels)
+					continue
 				}
 
 				if h.IsFloatHistogram() {
@@ -1567,6 +1577,12 @@ func (i *Ingester) pushSamplesToAppender(userID string, timeseries []mimirpb.Pre
 							return newExemplarTimestampTooFarInFutureError(model.Time(ex.TimestampMs), ts.Labels, ex.Labels)
 						})
 						continue
+					} else if ex.TimestampMs < minTimestampMs {
+						stats.failedExemplarsCount++
+						updateFirstPartial(nil, func() softError {
+							return newExemplarTimestampTooFarInPastError(model.Time(ex.TimestampMs), ts.Labels, ex.Labels)
+						})
+						continue
 					}
 
 					e := exemplar.Exemplar{

pkg/ingester/tenants_http.go

@@ -82,13 +82,17 @@ func (i *Ingester) TenantsHandler(w http.ResponseWriter, req *http.Request) {
 		s := tenantStats{}
 		s.Tenant = t
 		s.Blocks = len(db.Blocks())
+		minMillis := db.Head().MinTime()
 		s.MinTime = formatMillisTime(db.Head().MinTime())
 		maxMillis := db.Head().MaxTime()
 		s.MaxTime = formatMillisTime(maxMillis)
 
 		if maxMillis-nowMillis > i.limits.CreationGracePeriod(t).Milliseconds() {
 			s.Warning = "TSDB Head max timestamp too far in the future"
 		}
+		if i.limits.PastGracePeriod(t) > 0 && nowMillis-minMillis > (i.limits.PastGracePeriod(t)+i.limits.OutOfOrderTimeWindow(t)).Milliseconds() {
+			s.Warning = "TSDB Head min timestamp too far in the past"
+		}
 
 		tss = append(tss, s)
 	}

pkg/util/globalerror/user.go

@@ -26,6 +26,7 @@ const (
 	SeriesWithDuplicateLabelNames         ID = "duplicate-label-names"
 	SeriesLabelsNotSorted                 ID = "labels-not-sorted"
 	SampleTooFarInFuture                  ID = "too-far-in-future"
+	SampleTooFarInPast                    ID = "too-far-in-past"
 	MaxSeriesPerMetric                    ID = "max-series-per-metric"
 	MaxMetadataPerMetric                  ID = "max-metadata-per-metric"
 	MaxSeriesPerUser                      ID = "max-series-per-user"
@@ -68,6 +69,7 @@ const (
 	SampleDuplicateTimestamp ID = "sample-duplicate-timestamp"
 	ExemplarSeriesMissing    ID = "exemplar-series-missing"
 	ExemplarTooFarInFuture   ID = "exemplar-too-far-in-future"
+	ExemplarTooFarInPast     ID = "exemplar-too-far-in-past"
 
 	StoreConsistencyCheckFailed ID = "store-consistency-check-failed"
 	BucketIndexTooOld           ID = "bucket-index-too-old"