Sentinel quorum concept in Redis - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to specify the quorum number in Redis Sentinel configuration.

Redis

sentinel monitor mymaster 127.0.0.1 6379 [1]

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

A0

B2

C1

D3

Attempts:

3 left

💡 Hint

Common Mistakes

Setting quorum to 0 disables failover detection.

Setting quorum to 1 may cause false failovers.

The quorum value defines how many Sentinels need to agree before a failover is initiated. Usually, 3 is a common quorum number.

2fill in blank

medium

Complete the command to check the quorum value for a monitored master in Redis Sentinel.

Redis

SENTINEL quorum [1]

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

Amymaster

Bquorum

Cmaster1

Dfailover

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'quorum' as the master name causes errors.

Using 'failover' is not a valid master name.

The SENTINEL quorum <mastername> command returns the quorum value for the specified master.

3fill in blank

hard

Fix the error in the Sentinel configuration line to correctly set quorum to 2.

Redis

sentinel monitor mymaster 127.0.0.1 6379 [1]

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

Atwo

B2

C02

D0x2

Attempts:

3 left

💡 Hint

Common Mistakes

Using words like 'two' instead of digits.

Using hexadecimal or leading zeros.

The quorum must be a numeric integer value without quotes or prefixes.

4fill in blank

hard

Fill both blanks to complete the Sentinel failover timeout and parallel sync settings.

Redis

sentinel failover-timeout mymaster [1]
sentinel parallel-syncs mymaster [2]

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A180000

B1

C30000

D3

Attempts:

3 left

💡 Hint

Common Mistakes

Setting failover timeout too low causes premature failovers.

Setting parallel syncs too high may overload the master.

Failover timeout is usually set in milliseconds (e.g., 180000 ms = 3 minutes). Parallel syncs is the number of replicas synced at once, often 1.

5fill in blank

hard

Fill all three blanks to complete the Sentinel configuration for down-after-milliseconds, failover timeout, and quorum.

Redis

sentinel down-after-milliseconds mymaster [1]
sentinel failover-timeout mymaster [2]
sentinel monitor mymaster 127.0.0.1 6379 [3]

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

A10000

B180000

C2

D30000

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up timeout values.

Setting quorum too low or too high.

Down-after-milliseconds is the time to consider a master down (e.g., 10000 ms). Failover timeout is the max time for failover (e.g., 180000 ms). Quorum is the number of Sentinels needed to agree (e.g., 2).