Why replication is needed in MongoDB - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a replica set member in MongoDB configuration.

MongoDB

{ _id: 0, host: "localhost:27017", [1]: true }

Drag options to blanks, or click blank then click option'

AarbiterOnly

Bhidden

Cvotes

Dpriority

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing 'priority' with arbiterOnly.

Using 'votes' instead of arbiterOnly.

The arbiterOnly field is used to specify if the member is an arbiter in the replica set, which helps in elections but does not hold data.

2fill in blank

medium

Complete the command to check the status of a MongoDB replica set.

MongoDB

rs.[1]()

Drag options to blanks, or click blank then click option'

Aconfig

Bstatus

CisMaster

Dreconfig

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'config' instead of 'status'.

Trying 'isMaster' which shows primary info but not full status.

The rs.status() command shows the current status of the replica set members.

3fill in blank

hard

Fix the error in the command to add a new member to the replica set.

MongoDB

rs.add({ host: "localhost:[1]" })

Drag options to blanks, or click blank then click option'

A27018

B27017

C28017

D27016

Attempts:

3 left

💡 Hint

Common Mistakes

Using the same port 27017 for multiple members.

Choosing a port outside the typical MongoDB range.

Replica set members must run on different ports. The default port is 27017, so a new member should use a different port like 27018.

4fill in blank

hard

Fill both blanks to complete the MongoDB replica set initiation command with a name and members.

MongoDB

rs.initiate({ _id: [1], members: [ { _id: 0, host: [2] } ] })

Drag options to blanks, or click blank then click option'

A"rs0"

B"localhost:27017"

C"myReplicaSet"

D"127.0.0.1:27017"

Attempts:

3 left

💡 Hint

Common Mistakes

Using IP address instead of hostname.

Not quoting the replica set name.

The replica set name is a string like "rs0". The host must be a string with hostname and port, e.g., "localhost:27017".

5fill in blank

hard

Fill all three blanks to create a MongoDB replica set member with priority and votes settings.

MongoDB

{ _id: [1], host: [2], priority: [3] }

Drag options to blanks, or click blank then click option'

A1

B"localhost:27018"

C2

D"localhost:27017"

Attempts:

3 left

💡 Hint

Common Mistakes

Using string for _id instead of integer.

Setting priority as string instead of number.

The member _id is usually 1 or another integer. The host is a string with hostname and port. Priority is a number indicating election priority.