Rolling upgrades in Elasticsearch - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to start a rolling upgrade by setting the cluster to read-only mode.

Elasticsearch

PUT /_cluster/settings
{
  "persistent": {
    "cluster.blocks.read_only": [1]
  }
}

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

Afalse

Btrue

C"true"

D"false"

Attempts:

3 left

💡 Hint

Common Mistakes

Using string values like "true" instead of boolean true.

Setting the value to false which disables read-only mode.

Setting cluster.blocks.read_only to true makes the cluster read-only, which is a common step before starting a rolling upgrade.

2fill in blank

medium

Complete the code to update the index settings to disable replicas during the rolling upgrade.

Elasticsearch

PUT /my-index/_settings
{
  "index": {
    "number_of_replicas": [1]
  }
}

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

A0

B"1"

C"0"

D1

Attempts:

3 left

💡 Hint

Common Mistakes

Using string values like "0" instead of numeric 0.

Setting replicas to 1 which keeps replicas enabled.

Setting number_of_replicas to 0 disables replicas, which helps reduce overhead during rolling upgrades.

3fill in blank

hard

Fix the error in the code to check the cluster health status during the rolling upgrade.

Elasticsearch

GET /_cluster/health
{
  "wait_for_status": [1]
}

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

A"yellow"

Bgreen

C"green"

Dyellow

Attempts:

3 left

💡 Hint

Common Mistakes

Using unquoted status values causing syntax errors.

Using the wrong status string.

The wait_for_status parameter requires a string value like "green" or "yellow" enclosed in quotes.

4fill in blank

hard

Fill both blanks to update the cluster settings to disable shard allocation and then re-enable it after the upgrade.

Elasticsearch

PUT /_cluster/settings
{
  "transient": {
    "cluster.routing.allocation.enable": [1]
  }
}

PUT /_cluster/settings
{
  "transient": {
    "cluster.routing.allocation.enable": [2]
  }
}

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

A"none"

B"all"

C"primaries"

D"new_primaries"

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect allocation values like "primaries" or "new_primaries".

Forgetting to use quotes around the values.

Setting cluster.routing.allocation.enable to "none" disables shard allocation during upgrade, and setting it back to "all" re-enables it.

5fill in blank

hard

Fill all three blanks to create a script that disables shard allocation, waits for green status, and then re-enables allocation.

Elasticsearch

PUT /_cluster/settings
{
  "transient": {
    "cluster.routing.allocation.enable": [1]
  }
}

GET /_cluster/health
{
  "wait_for_status": [2],
  "timeout": "30s"
}

PUT /_cluster/settings
{
  "transient": {
    "cluster.routing.allocation.enable": [3]
  }
}

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

A"none"

B"green"

C"all"

D"yellow"

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong status values like "yellow" instead of "green".

Not using quotes around string values.

Mixing up the order of disabling and enabling allocation.

This script disables shard allocation with "none", waits for the cluster to reach "green" status, then re-enables allocation with "all".