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To provide high availability and data consistency, in a production sharded cluster, each shard is a _____
______ interface with client applications and direct operations to the appropriate shard or shards.
A sharded cluster can contain __________ query router to divide the client request load.
Point out the correct statement.
_____ servers store the cluster’s metadata.
The query router uses __________ to target operations to specific shards.
Point out the wrong statement.
Production sharded clusters have exactly ______ config servers.
A _________ key is either an indexed field or an indexed compound field that exists in every document in the collection.
To divide the shard key values into chunks, MongoDB uses _____ based partitioning.
With hash based partitioning, two documents with _____ shard key values are unlikely to be part of the same chunk.
__ based partitioning, by contrast, ensures an even distribution of data at the expense of efficient range queries.
MongoDB allows administrators to direct the balancing policy using ______ aware sharding.
Point out the correct statement.
Tags are the primary mechanism to control the behavior of the _______ and the distribution of chunks in a cluster.
How many background process runs behind balanced cluster?
Point out the wrong statement.
_____ is a background process that keeps chunks from growing too large.
The shards manage _______ migrations as a background operation between an origin shard and a destination shard.
For most deployments, the default value of chunk is _____ megabytes is ideal.
The ______ instances are the routers for the cluster.
A single sharded cluster must have exclusive use of its _______ servers.
When a chunk grows beyond the chunk size, MongoDB attempts to split the chunk into smaller chunks, always based on ranges in the _____
Point out the correct statement.
The index on the shard key cannot be a _________ index.
Hashed shard keys use a ________ index of a single field as the shard key to partition data across your sharded cluster.
Point out the correct statement.
You can control how many chunks MongoDB will create with the ___________ parameter.
MongoDB automatically computes the hashes when resolving queries using ______ indexes.
MongoDB generates _______ values upon document creation to produce a unique identifier for the object.
A shard key that increases monotonically will not hinder performance if most of your write operations are ____ operations.
The mongos provides an interface for applications to interact with sharded clusters that hides the complexity of data ______
The _________ process is responsible for redistributing the chunks of a sharded collection evenly among the shards for every sharded collection.
Point out the correct statement.
Use _______ migration to distribute data during bulk inserts.
The balancer process sends the _______ command to the source shard.
Point out the wrong statement.
The source shard is responsible for incoming ______ operations for the chunk.
_____ can alter the behavior so that the delete phase of the current migration blocks the start of the next chunk migration.
The default value _________ becomes true for all chunk migrations.
You can set the _________ option on the balancer configuration to set different write concern semantics.
With __________ enabled, the source shard archives the documents in the migrated chunks in a directory named after the collection namespace.
The ________ collection stores a document for each change to the metadata of a sharded collection.
Point out the correct statement.
The _________ collection stores a document for each sharded collection in the cluster.
You can return a list of the collections, with the following helper ______
Point out the wrong statement.
_____ is a string that holds the address of the client, a mongos instance that initiates this change.
The _______ collection keeps track of the active components in the sharded cluster.
If the collection is empty then MongoDB will create the index as part of the ________