OpenSearch _sourceOpenSearch keeps the original JSON document in a field called _source. The source field serves special purposes such as...
OpenSearch AggregationsThe aggregations framework is a tool built in every OpenSearch deployment. The different aggregation types: Bucket, Metric & Pipeline...
OpenSearch AliasAn OpenSearch alias is a secondary name to refer to one or more indices. Aliases can be created and deleted dynamically using...
OpenSearch BulkOpenSearch bulk makes it possible to perform many write operations in a single API call, which increases indexing speed. Using bulk API...
OpenSearch Circuit BreakersOpenSearch has circuit breakers to deal with OutOfMemory errors that cause nodes to crash. To size a circuit breaker...
OpenSearch ClientOfficial OpenSearch clients are available for java, Perl, PHP, python, ruby and .NET. The official clients follow a similar structure and...
OpenSearch ClusterAn OpenSearch cluster is a group of servers (nodes) working together to store data & respond to requests. The key elements of clustering...
OpenSearch DELETEDELETE is an OpenSearch API that removes a document from a specific index. It requires an index name & _id document to delete the document.
OpenSearch Delete By QueryOpenSearch delete by query is an API, which provides functionality to delete all documents based on the matching query. If you don't...
OpenSearch DeprecationTo find out which functions have been deprecated in OpenSearch, you can use deprecation logs, deprecation API, read breaking pages...
OpenSearch DiscoveryOpenSearch discovery occurs when a node starts, restarts or loses contact with the master node. The discovery.seed_hosts...
OpenSearch Disk ThresholdOpenSearch uses several parameters to enable it to manage hard disk storage across the cluster, such as...
OpenSearch DocumentEach OpenSearch document is a JSON structure, which is ultimately considered to be a series of key:value pairs. An example for creating...
OpenSearch FielddataIn OpenSearch the term Fielddata is relevant when performing sorting and aggregations on text field. To set fielddata=true, you...
OpenSearch FilterAn OpenSearch filter applies conditions inside the query to narrow down the matching results. A filter clause can be used used in...
OpenSearch High CPUHigh CPU in OpenSearch is often a symptom of other underlying issues. It should be fixed since a distressed node will slow query response...
OpenSearch IndexAn OpenSearch index contains a schema and can have one or more shards and replicas. Here's how to create, delete, list, and query an index.
OpenSearch IndexingIndexing is the process of adding or updating new documents to an OpenSearch index. To index a document...
OpenSearch LuceneOpenSearch Lucene or Apache Lucene is an open-source Java library used as a search engine. OpenSearch is built on top of Lucene...
OpenSearch MappingAn OpenSearch mapping contains the properties of each field in the index. A common issue is an incorrectly defined mapping. To update...
OpenSearch MetadataOpenSearch metadata refers to additional information stored for each document using metadata fields. Metadata fields can be customized...
OpenSearch Nodes & Node RolesThere are different types of OpenSearch nodes. Each has its own role and purpose. Cluster-Manager, coordinating and data node roles differ...
OpenSearch Persistent SettingsIn OpenSearch, Persistent refers to cluster settings that persist across cluster restarts. Examples of persistent settings include...
OpenSearch PluginsPlugins in OpenSearch are used to extend the functionality of OpenSearch. To install and uninstall an OpenSearch plugin...
OpenSearch QueueQueues in OpenSearch exist in the context of Thread Pools. Queues are used to hold the pending requests for thread pools. For example...
OpenSearch RebalanceCluster rebalancing is the process by which an OpenSearch cluster distributes data across the nodes. To force rebalance manually...
OpenSearch RecoveryIn OpenSearch, recovery refers to the process of recovering an index or shard when something goes wrong. The recovery API can be used by...
OpenSearch Red StatusOpenSearch red status indicates not only that the primary shard has been lost, but also that a replica has not been promoted...
OpenSearch Refresh IntervalOpenSearch requires a refresh operation to make indexed information available for search. You can set an OpenSearch refresh_interval by...
OpenSearch ReindexOpenSearch reindex is the concept of copying existing data from a source index to a destination index. The reindex API is...
OpenSearch ReplicationOpenSearch replication refers to storing a redundant copy of the data. Replicas are used to provide high availability and failover of...
OpenSearch RepositoryAn OpenSearch repository needs to be registered using the _snapshot endpoint. The supported repository types are: S3, HDFS, Azure...
OpenSearch RestoreIn OpenSearch, restore refers to a snapshot restore mechanism. To restore a snapshot, an index, or selected indices...
OpenSearch RoutingIn OpenSearch, routing refers to document routing. OpenSearch will determine which shard the document will be routed to for indexing when...
OpenSearch ScrollThe OpenSearch scroll API is useful when a search returns a large set of results. Large search results are exhaustive for the system...
OpenSearch SearchTo search in OpenSearch, send a GET request to the _search endpoint in the search API. In the query phase and the fetch phase there are...
OpenSearch Search Rejected QueueAn OpenSearch cluster can start to reject search requests for several reasons. To resolve this, check the state of the thread pool and..
OpenSearch SettingsOpenSearch settings can be configured on the cluster-level, node-level and index-level. Here's how to set up and optimize your settings.
OpenSearch ShardsEach OpenSearch shard is an Apache Lucene index. The number of shards is set when an index is created, and cannot be changed without...
OpenSearch Shards Too LargeIt is a best practice that OpenSearch shard size should not go above 50GB for a single shard. If you go above this limit...
OpenSearch SnapshotAn OpenSearch snapshot is a backup of an index taken from a running cluster. It's better to use snapshots instead of disk backups due...
OpenSearch TaskAn OpenSearch task is equivalent to an operation. OpenSearch provides a dedicated task API for the task management, which includes actions...
OpenSearch TemplateAn OpenSearch template falls into one of these categories: index templates or search templates. To create a dynamic index template...
OpenSearch ThreadpoolOpenSearch threadpools are used to manage how requests are processed and to optimize the use of resources. An example of...
OpenSearch UpgradeAn OpenSearch upgrade of an existing cluster can be done in 2 ways: through a rolling upgrade or a full cluster restart. To update...
OpenSearch VersionA version corresponds to the OpenSearch built-in tracking system that tracks the changes in each document. By using _version...
OpenSearch Yellow StatusAn OpenSearch yellow status indicates that one or more of the replica shards on the cluster are not allocated to a node. This could occur...