> For the complete MongoDB documentation index, see www.mongodb.com/docs/llms.txt

# Inconsistency Types

**New in version 7.0**

The [`checkMetadataConsistency`](https://www.mongodb.com/docs/manual/reference/command/checkmetadataconsistency.md#mongodb-dbcommand-dbcmd.checkMetadataConsistency) command performs a series of consistency checks on sharding metadata and indexes and returns an array of inconsistency documents.

| Inconsistency Type | Description |
| --- | --- |
| [`AuthoritativeShardCatalogCollectionsPresent`](https://www.mongodb.com/docs/manual/reference/inconsistency-type/authoritativeshardcatalogcollectionspresent.md#mongodb-data-AuthoritativeShardCatalogCollectionsPresent) | A collection exists in the `config.shard.catalog.*` namespace on a shard where it should not exist. **New in version 9.0** |
| [`CollectionAuxiliaryMetadataMismatch`](https://www.mongodb.com/docs/manual/reference/inconsistency-type/collectionauxiliarymetadatamismatch.md#mongodb-data-CollectionAuxiliaryMetadataMismatch) | A collection contains mismatching auxiliary metadata across different shards. **New in version 8.1** |
| [`CollectionOptionsMismatch`](https://www.mongodb.com/docs/manual/reference/inconsistency-type/collectionoptionsmismatch.md#mongodb-data-CollectionOptionsMismatch) | A collection contains mismatching options across different shards. **New in version 8.0** (*Also available starting in 7.0.23*) |
| [`CollectionUUIDMismatch`](https://www.mongodb.com/docs/manual/reference/inconsistency-type/collectionuuidmismatch.md#mongodb-data-CollectionUUIDMismatch) | A collection exists on a shard with a locally registered UUID that differs from the one registered in the [`config.collections`](https://www.mongodb.com/docs/manual/reference/config-database.md#mongodb-data-config.collections) cluster catalog. **New in version 7.0** |
| [`CorruptedChunkShardKey`](https://www.mongodb.com/docs/manual/reference/inconsistency-type/corruptedchunkshardkey.md#mongodb-data-CorruptedChunkShardKey) | The routing table contains a chunk with a min key or max key that doesn't correspond to the collection shard key. **New in version 7.0** |
| [`CorruptedZoneShardKey`](https://www.mongodb.com/docs/manual/reference/inconsistency-type/corruptedzoneshardkey.md#mongodb-data-CorruptedZoneShardKey) | The routing table contains a zone with a min key or max key that doesn't correspond to the collection shard key. **New in version 7.0** |
| [`HiddenShardedCollection`](https://www.mongodb.com/docs/manual/reference/inconsistency-type/hiddenshardedcollection.md#mongodb-data-HiddenShardedCollection) | A collection is registered in the [`config.collections`](https://www.mongodb.com/docs/manual/reference/config-database.md#mongodb-data-config.collections) cluster catalog under a non-existent database. **New in version 7.0** |
| [`IncompatibleUniqueIndexOnShardedCollection`](https://www.mongodb.com/docs/manual/reference/inconsistency-type/incompatibleuniqueindexonshardedcollection.md#mongodb-data-IncompatibleUniqueIndexOnShardedCollection) | An index on a sharded collection has index options that are incompatible with uniqueness requirements. **New in version 8.3** |
| [`InconsistentIndex`](https://www.mongodb.com/docs/manual/reference/inconsistency-type/inconsistentindex.md#mongodb-data-InconsistentIndex) | An index exists on two different shards that contains differing metadata or a specific index is missing on some shards. **New in version 7.0** |
| [`InconsistentShardCatalogCollectionMetadata`](https://www.mongodb.com/docs/manual/reference/inconsistency-type/inconsistentshardcatalogcollectionmetadata.md#mongodb-data-InconsistentShardCatalogCollectionMetadata) | Collection metadata for a sharded collection differs between the config server and the shard catalog. **New in version 9.0** |
| [`LegacyShardCacheCollectionsPresent`](https://www.mongodb.com/docs/manual/reference/inconsistency-type/legacyshardcachecollectionspresent.md#mongodb-data-LegacyShardCacheCollectionsPresent) | A collection exists in the `config.cache.*` namespace on a shard where it should not exist. **New in version 9.0** |
| [`MisplacedCollection`](https://www.mongodb.com/docs/manual/reference/inconsistency-type/misplacedcollection.md#mongodb-data-MisplacedCollection) | Indicates that an unsharded collection exists on the incorrect shard and was not moved with [`moveCollection`.](https://www.mongodb.com/docs/manual/reference/command/movecollection.md#mongodb-dbcommand-dbcmd.moveCollection) **New in version 7.0** **Changed in version 8.0** |
| [`MissingLocalCollection`](https://www.mongodb.com/docs/manual/reference/inconsistency-type/missinglocalcollection.md#mongodb-data-MissingLocalCollection) | A collection is registered on the sharding catalog but does not exist on the corresponding shard. **New in version 8.0** |
| [`MissingRoutingTable`](https://www.mongodb.com/docs/manual/reference/inconsistency-type/missingroutingtable.md#mongodb-data-MissingRoutingTable) | A sharded collection exists without a routing table. **New in version 7.0** |
| [`MissingShardKeyIndex`](https://www.mongodb.com/docs/manual/reference/inconsistency-type/missingshardkeyindex.md#mongodb-data-MissingShardKeyIndex) | A sharded collection exists that doesn't have an index compatible with the collection shard key. **New in version 7.0** |
| [`RangeDeletionMissingShardKeyIndex`](https://www.mongodb.com/docs/manual/reference/inconsistency-type/rangedeletionmissingshardkeyindex.md#mongodb-data-RangeDeletionMissingShardKeyIndex) | A sharded collection exists that doesn't have an index compatible with the collection shard key and there is at least one remaining range deletion task to complete. **New in version 8.2** |
| [`RoutingTableMissingMaxKey`](https://www.mongodb.com/docs/manual/reference/inconsistency-type/routingtablemissingmaxkey.md#mongodb-data-RoutingTableMissingMaxKey) | A range gap exists in the routing table. The last chunk boundary in the routing table does not reach the maximum key value. **New in version 7.0** |
| [`RoutingTableMissingMinKey`](https://www.mongodb.com/docs/manual/reference/inconsistency-type/routingtablemissingminkey.md#mongodb-data-RoutingTableMissingMinKey) | A range gap exists in the routing table. The first chunk does not start from the minimum key value. **New in version 7.0** |
| [`RoutingTableRangeGap`](https://www.mongodb.com/docs/manual/reference/inconsistency-type/routingtablerangegap.md#mongodb-data-RoutingTableRangeGap) | A range gap exists in the routing table between two consecutive chunks for the same collection. **New in version 7.0** |
| [`RoutingTableRangeOverlap`](https://www.mongodb.com/docs/manual/reference/inconsistency-type/routingtablerangeoverlap.md#mongodb-data-RoutingTableRangeOverlap) | The routing table of a collection contains two chunks with overlapping shard key ranges. **New in version 7.0** |
| [`TrackedUnshardedCollectionHasInvalidKey`](https://www.mongodb.com/docs/manual/reference/inconsistency-type/trackedunshardedcollectionhasinvalidkey.md#mongodb-data-TrackedUnshardedCollectionHasInvalidKey) | An unsharded collection has an invalid shard key. **New in version 8.0** |
| [`TrackedUnshardedCollectionHasMultipleChunks`](https://www.mongodb.com/docs/manual/reference/inconsistency-type/trackedunshardedcollectionhasmultiplechunks.md#mongodb-data-TrackedUnshardedCollectionHasMultipleChunks) | An unsharded collection contains multiple chunks. **New in version 8.0** |
| [`ZonesRangeOverlap`](https://www.mongodb.com/docs/manual/reference/inconsistency-type/zonesrangeoverlap.md#mongodb-data-ZonesRangeOverlap) | Overlapping zones exist for the same collection. **New in version 7.0** |