Why clustering provides horizontal scaling in Redis - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to add a node to a Redis cluster.

Redis

redis-cli --cluster add-node [1] 127.0.0.1:7000

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

A127.0.0.1:7002

B127.0.0.1:7001

C127.0.0.1:7004

D127.0.0.1:7003

Attempts:

3 left

💡 Hint

Common Mistakes

Using the existing cluster node address instead of the new node address.

Confusing the order of IP addresses.

The command adds the node at 127.0.0.1:7001 to the cluster with the existing node at 127.0.0.1:7000.

2fill in blank

medium

Complete the code to create a Redis cluster with 3 nodes.

Redis

redis-cli --cluster create 127.0.0.1:7000 [1] 127.0.0.1:7002 --cluster-replicas 0

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

A127.0.0.1:7001

B127.0.0.1:7003

C127.0.0.1:7004

D127.0.0.1:7005

Attempts:

3 left

💡 Hint

Common Mistakes

Using a node address outside the intended cluster range.

Skipping a node address.

The cluster is created with nodes 7000, 7001, and 7002.

3fill in blank

hard

Fix the error in the command to reshard slots in a Redis cluster.

Redis

redis-cli --cluster reshard [1] --cluster-from 0 --cluster-to 1 --cluster-slots 5000

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

A127.0.0.1:7002

B127.0.0.1:7000

C127.0.0.1:7001

D127.0.0.1:7003

Attempts:

3 left

💡 Hint

Common Mistakes

Using an address not in the cluster.

Using a node that is down or unreachable.

The reshard command requires the address of the node to connect to, here 127.0.0.1:7001.

4fill in blank

hard

Fill both blanks to assign hash slots evenly across 3 nodes in a Redis cluster.

Redis

redis-cli --cluster create 127.0.0.1:7000 [1] [2] --cluster-replicas 0

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

A127.0.0.1:7001

B127.0.0.1:7002

C127.0.0.1:7003

D127.0.0.1:7004

Attempts:

3 left

💡 Hint

Common Mistakes

Using non-consecutive or wrong node addresses.

Including nodes not intended for the cluster.

The cluster is created with nodes 7000, 7001, and 7002 to distribute slots evenly.

5fill in blank

hard

Fill all three blanks to create a dictionary of node IDs mapped to their IP addresses in Redis cluster info.

Redis

nodes = { [1]: '[2]', '[3]': '127.0.0.1:7001'}

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

A'node-1'

B127.0.0.1:7000

C'node-0'

D127.0.0.1:7002

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing keys and values or missing quotes.

Using IP addresses as keys without quotes.

This dictionary maps node IDs to their IP addresses for cluster management.