Why templates standardize index creation in Elasticsearch - Challenge Your Understanding

Challenge - 5 Problems

🧠 Conceptual

intermediate

Why use index templates in Elasticsearch?

Which of the following best explains why index templates are used to standardize index creation in Elasticsearch?

A They automatically apply consistent settings and mappings to new indices matching a pattern.

B They speed up search queries by caching results permanently.

C They delete old indices automatically to save disk space.

D They encrypt all data stored in the index for security.

💡 Hint

Think about how templates help keep index structure consistent.

Index templates ensure that every new index matching a pattern has the same settings and mappings, which keeps data organized and queries reliable.

❓ query_result

intermediate

Result of applying an index template

Given an index template that sets the number_of_shards to 3 for indices starting with 'logs-', what will be the number_of_shards for a new index named 'logs-2024-06'?

A 1

B Depends on the cluster default

C 5

D 3

💡 Hint

Templates override default shard settings for matching indices.

The template applies the number_of_shards setting to all indices matching 'logs-*', so 'logs-2024-06' will have 3 shards.

📝 Syntax

advanced

Identify the correct JSON snippet for an index template

Which JSON snippet correctly defines an index template that applies to indices starting with 'app-' and sets the refresh_interval to '30s'?

A { "index_patterns": ["app-*"], "settings": { "refresh_interval": "30s" } }

B { "pattern": "app-*", "settings": { "refresh_interval": 30 } }

C { "index_patterns": "app-*", "settings": { "refresh_interval": "30s" } }

D { "index_patterns": ["app-*"], "refresh_interval": "30s" }

💡 Hint

Look for correct keys and value types in the JSON.

The correct key is 'index_patterns' with an array of patterns, and 'settings' contains the refresh_interval as a string.

❓ optimization

advanced

Optimizing index template usage for multiple similar indices

You have multiple indices for different regions like 'sales-us', 'sales-eu', and 'sales-asia'. How can you optimize index template usage to standardize their creation?

A Create separate templates for each region with identical settings.

B Manually configure each index after creation.

C Create one index template with pattern 'sales-*' to apply common settings and mappings.

D Use a wildcard '*' template that applies to all indices.

💡 Hint

Think about how to reduce repetition and ensure consistency.

A single template with a pattern matching all sales indices ensures consistent settings and reduces maintenance.

🔧 Debug

expert

Why does an index not inherit template settings?

You created an index template with pattern 'data-*' setting number_of_replicas to 2. However, a new index named 'data-2024' has number_of_replicas set to 1. What is the most likely reason?

A Elasticsearch does not apply templates to replica settings.

B The index was created before the template was added.

C The cluster default always overrides templates.

D The template pattern does not match the index name.

💡 Hint

Consider when templates are applied during index lifecycle.

Templates apply only when an index is created. If the index existed before the template, it won't inherit those settings.