{
  "schema_version": 2,
  "id": "glossary",
  "title": "Glossary",
  "url": "https://redis.io/docs/latest/glossary/",
  "summary": "",
  "aliases": [
    "/glossary/"
  ],
  "tags": [
    "Glossary"
  ],
  "last_updated": "2026-10-06T08:53:14-07:00",
  "children": [],
  "page_type": "content",
  "content_hash": "0db7191f41547cf98eea59b2b8bfcf6b5dca6f4784a108781e255604d27a2ee7",
  "sections": [
    {
      "id": "overview",
      "title": "Overview",
      "role": "overview",
      "text": "<dl class=\"glossary\">"
    },
    {
      "id": "letter-a",
      "title": "A, B",
      "role": "content",
      "text": "Allows you to manage permissions based on key patterns.\n\nMore info: [redis.io/operate/oss_and_stack/management/security/acl](https://redis.io/docs/latest/operate/oss_and_stack/management/security/acl); [ACL wikipedia](https://en.wikipedia.org/wiki/Access-control_list); [Database access control](https://redis.io/docs/latest/operate/rs/security/access-control); [Update database ACLs](https://redis.io/docs/latest/operate/rs/security/access-control/ldap/update-database-acls); [Role-based access control](https://redis.io/docs/latest/operate/rc/security/access-control/data-access-control/role-based-access-control)\n\n\n<a name=\"active-active\"></a>\n\nGeo-distributed databases that span multiple [Redis Enterprise Software](https://redis.io/docs/latest/#redis-enterprise-software) [clusters](https://redis.io/docs/latest/#cluster). Active-Active databases, also known as conflict-free replicated databases (CRDB), depend on [multi-primary replication](https://redis.io/docs/latest/#multi-primary-replication) and [conflict-free replicated data types (CRDTs)](https://redis.io/docs/latest/#conflict-free-replicated-data-types-crdt) to power a simple development experience for geo-distributed applications.\n\nMore info: [Active-Active geo-distributed Redis](https://redis.io/docs/latest/operate/rs/databases/active-active), [Geo-distributed Active-Active Redis applications](https://redis.io/docs/latest/operate/rs/databases/active-active/), [Developing applications for Active-Active databases](https://redis.io/docs/latest/operate/rs/databases/active-active/develop/)\n\n\n\nA \"member database\" of a global [Active-Active database](https://redis.io/docs/latest/#active-active) which is made up of its own master and replica [shards](https://redis.io/docs/latest/#shard) spanning a single [cluster](https://redis.io/docs/latest/#cluster).\n\nMore info: [Active-Active database instances](https://redis.io/docs/latest/operate/rs/databases/active-active/create)\n\n\n\nProvides applications read-only access to replicas of the data set from different geographical locations. The Redis Enterprise implementation of active-passive [replication](https://redis.io/docs/latest/#replication) is called [Replica Of](https://redis.io/docs/latest/#replica-of).\n\nMore info: [Database replication](https://redis.io/docs/latest/operate/rs/databases/durability-ha/replication), [Replica Of](https://redis.io/docs/latest/operate/rs/databases/import-export/replica-of)\n\n\n\nEach node runs a web server that is used to provide the user with access to the Redis Enterprise Software admin console (previously known as management UI). The admin console allows viewing and managing the entire [cluster](https://redis.io/docs/latest/#cluster), so it does not matter which [node](https://redis.io/docs/latest/#redis-enterprise-nodes) is used to access it.\n\nMore info: [Manage clusters](https://redis.io/docs/latest/operate/rs/clusters)\n\n\n\nA piece of code that intercepts requests to the Kubernetes API server prior to persistence of the object.\n\nMore info: [Using Admission Controllers](https://kubernetes.io/docs/reference/access-authn-authz/admission-controllers/)\n\n\n\nLog files that keep a record of data changes by writing to the end of a file. This happens with every write, or every second to allow data recovering the entire\ndataset by replaying the append-only log from the beginning to the end.\n\nMore info: [Data Persistence](https://redis.io/docs/latest/operate/rc/databases/configuration/data-persistence), [Data Persistence with Redis Enterprise Software](https://redis.io/docs/latest/operate/rs/databases/configure/database-persistence)\n\n\n\nA probabilistic data structure that tests whether an element is a member of a set. False positive matches are possible, but false negatives are not. Bloom filters are space-efficient and provide fast membership testing.\n\nMore info: [Bloom filters](https://redis.io/docs/latest/develop/data-types/probabilistic/bloom-filter), [RedisBloom](https://redis.io/docs/latest/operate/oss_and_stack/stack-with-enterprise/bloom)"
    },
    {
      "id": "letter-c",
      "title": "C",
      "role": "content",
      "text": "A distributed database is causally consistent if it maintains the same order of operations on a piece of data across all database copies.\n\nMore info: [Causal consistency wikipedia](https://en.wikipedia.org/wiki/Causal_consistency), [Causal consistency in an Active-Active database](https://redis.io/docs/latest/operate/rs/databases/active-active/causal-consistency)\n\n\n\nClassless Inter-Domain Routing (CIDR) is a method to allocate and route IP addresses. A CIDR allowlist defines a range of IP addresses and permits connections to them.\n\nMore info: [CIDR wikipedia](https://en.wikipedia.org/wiki/Classless_Inter-Domain_Routing), [Configure CIDR allowlist](https://redis.io/docs/latest/operate/rc/security/cidr-whitelist)\n\n\n\nConcurrency or updates and writes refer to more than events that happen at the same wall clock time across member [Active-Active databases](https://redis.io/docs/latest/#active-active). Concurrent updates refer to the fact that updates happen in between sync events that catch up member Active-Active databases with updates that happened on other member Active-Active databases.\n\nMore info: [Developing applications for Active-Active databases](https://redis.io/docs/latest/operate/rs/databases/active-active/develop), [Conflict-free replicated data types (CRDT)](https://redis.io/docs/latest/#conflict-free-replicated-data-types-crdt)\n\n\n\n\nConsistency models describe the way a distributed system keeps replicated data consistent between copies.\n\nMore info: [Consistency models](https://en.wikipedia.org/wiki/Consistency_model)\n\n\n\n\nA Redis Enterprise cluster is composed of identical nodes that are deployed within a data center or stretched across local availability zones.\n\nMore info: [Database clustering](https://redis.io/docs/latest/operate/rc/databases/configuration/clustering)\n\n\n\nAn internally managed [Redis database](https://redis.io/docs/latest/#redis-enterprise-database) that acts as a single repository for all [cluster](https://redis.io/docs/latest/#cluster) metadata.\n\nMore info: [Redis Enterprise cluster architecture](https://redis.io/docs/latest/operate/rs/clusters)\n\n\n\nA collection of Redis Enterprise services responsible for [provisioning](https://redis.io/docs/latest/#provisioning), [migration](https://redis.io/docs/latest/#migration), monitoring, [re-sharding](https://redis.io/docs/latest/#re-sharding), [rebalancing](https://redis.io/docs/latest/#rebalancing), de-provisioning, auto-scaling.\n\nMore info: [Redis Enterprise cluster architecture](https://redis.io/docs/latest/operate/rs/clusters), [Database operations](https://redis.io/docs/latest/operate/rs/databases)\n\n\n\n\nConflict-free replicated databases (CRDB) are an alternate name for [Active-Active databases](#active-active).\n\n\n\nTechniques used by Redis data types in Active-Active databases that handle conflicting concurrent writes across member Active-Active databases. The Redis Enterprise implementation of CRDT is called an Active-Active database (formerly known as CRDB).\n\nMore info: [CRDT info](https://redis.io/docs/latest/operate/rs/databases/active-active/develop/#info), [Active-Active geo-distributed Redis](https://redis.io/docs/latest/operate/rs/databases/active-active), [CRDT wikipedia](https://en.wikipedia.org/wiki/Conflict-free_replicated_data_type)\n\n\n\nControl loops that watch the state of your Kubernetes cluster and make or request changes where needed to move the current cluster state closer to the desired state.\n\nMore info: [Controllers](https://kubernetes.io/docs/concepts/architecture/controller/)\n\n\n\nExtensions of the Kubernetes API that allow you to store and retrieve structured data. Custom resources let you extend Kubernetes capabilities without modifying the core Kubernetes code.\n\nMore info: [Custom Resources](https://kubernetes.io/docs/concepts/extend-kubernetes/api-extension/custom-resources/)\n\n\n\nA cluster-wide resource that specifies which settings can be configured via custom resource files. CRDs define the structure and validation rules for custom resources.\n\nMore info: [CustomResourceDefinition](https://kubernetes.io/docs/reference/glossary/?fundamental=true#term-CustomResourceDefinition), [Custom Resources](https://kubernetes.io/docs/concepts/extend-kubernetes/api-extension/custom-resources/)"
    },
    {
      "id": "letter-d",
      "title": "D - F",
      "role": "content",
      "text": "Defines how excess data is handled when the [database](https://redis.io/docs/latest/#redis-enterprise-database) exceeds the memory limit.\n\nMore info: [Data Eviction Policy](https://redis.io/docs/latest/operate/rc/databases/configuration/data-eviction-policies), [Redis Enterprise data eviction](https://redis.io/docs/latest/operate/rs/databases/memory-performance/eviction-policy)\n\n\n\nA configuration approach where you specify the desired state of your system, and the system automatically makes the necessary changes to achieve that state.\n\nMore info: [Managing Kubernetes Objects Using Declarative Configuration](https://kubernetes.io/docs/tasks/manage-kubernetes-objects/declarative-config/)\n\n\n\nFeatures are marked as _deprecated_ when they're scheduled to be removed from our products, generally because they've been replaced by new features.\n\nFor details, see [obsolete](#obsolete).\n\n\n\nNaming system for computers, services, or other resources connected to the Internet or a private network. It associates various information with domain names assigned to each of the participating entities.\n\nMore info: [DNS wikipedia](https://en.wikipedia.org/wiki/Domain_Name_System)\n\n\n\n\nAfter updating data on one instance of a distributed database, the other database copies may have stale data for a short time while they sync. Eventual consistency means that the updated data will eventually be the same across all database copies.\n\nMore info: [Eventual consistency wikipedia](https://en.wikipedia.org/wiki/Eventual_consistency)\n\n\n\nThe automatic process of switching to a backup system when the primary system fails. In Redis Enterprise, failover promotes replica shards to primary when the original primary becomes unavailable.\n\nMore info: [High availability](https://redis.io/docs/latest/operate/rs/databases/durability-ha), [Replica HA](https://redis.io/docs/latest/operate/rs/databases/configure/replica-ha)\n\n\n\nA domain name that includes a list of domain labels to specify the exact location in the DNS.\n\nMore info: [FQDN wikipedia](https://en.wikipedia.org/wiki/Fully_qualified_domain_name)\n\n\n\n\nLinux command to synchronize a file's in-core state with a storage device. Used in [data persistence](https://redis.io/docs/latest/operate/rs/databases/configure/database-persistence) operations.\n\nMore info: [`fsync` man page](https://man7.org/linux/man-pages/man2/fsync.2.html), [Data persistence](https://redis.io/docs/latest/operate/rs/databases/configure/database-persistence)\n\n\n\nA search technique that examines all words in every stored document to find matches to search criteria. Redis provides full-text search capabilities through its Search and Query features.\n\nMore info: [Redis Search](https://redis.io/docs/latest/develop/ai/search-and-query), [Full-text search](https://redis.io/docs/latest/develop/ai/search-and-query/query/full-text)"
    },
    {
      "id": "letter-g",
      "title": "G - J",
      "role": "content",
      "text": "The process of creating data structures that improve the speed of data retrieval operations. Redis supports various types of indexing including secondary indexing, vector indexing, and full-text indexing.\n\nMore info: [Redis Search](https://redis.io/docs/latest/develop/ai/search-and-query), [Indexing concepts](https://redis.io/docs/latest/develop/ai/search-and-query/advanced-concepts)\n\n\n\nJavaScript Object Notation (JSON) is a lightweight data-interchange format. Redis provides native JSON support through RedisJSON, allowing you to store, update, and retrieve JSON values.\n\nMore info: [JSON data type](https://redis.io/docs/latest/develop/data-types/json), [RedisJSON](https://redis.io/docs/latest/operate/oss_and_stack/stack-with-enterprise/json)\n\n\n\nThe result of a hash calculation used in [database clustering](https://redis.io/docs/latest/operate/rs/databases/durability-ha/clustering) to determine which [shard](https://redis.io/docs/latest/#shard) stores a particular key.\n\nMore info: [Database clustering](https://redis.io/docs/latest/operate/rs/databases/durability-ha/clustering), [Sharding](https://redis.io/docs/latest/#sharding)\n\n\n\nA part of the key that is used in the hash calculation to determine the [hash slot](https://redis.io/docs/latest/#hash-slot) for [database clustering](https://redis.io/docs/latest/operate/rs/databases/durability-ha/clustering).\n\nMore info: [Database clustering](https://redis.io/docs/latest/operate/rs/databases/durability-ha/clustering), [Hash slots](https://redis.io/docs/latest/#hash-slot)\n\n\n\n\nHigh availability (HA) is a characteristic of distributed systems that keeps systems available for users for longer than normal periods of time. This is done by reducing single points of failure, increasing redundancy, and making recovering from failures easier.\n\nMore info: [Redis Enterprise durability and high availability](https://redis.io/docs/latest/operate/rs/databases/durability-ha/), [High availability wikipedia](https://en.wikipedia.org/wiki/High_availability)\n\n\n\nAn API object that manages external access to the services in a Kubernetes cluster, typically HTTP.\n\nMore info: [Ingress](https://kubernetes.io/docs/concepts/services-networking/ingress/), [Ingress routing for Redis Enterprise for Kubernetes](https://redis.io/docs/latest/operate/kubernetes/networking/ingress)"
    },
    {
      "id": "letter-k",
      "title": "K, L",
      "role": "content",
      "text": "A command-line tool for communicating with a Kubernetes API server.\n\nMore info: [Overview of kubectl](https://kubernetes.io/docs/reference/kubectl/overview/)\n\n\n\nA protocol for accessing and maintaining distributed directory services over an IP network, often used to authenticate users.\n\nMore info: [LDAP wikipedia](https://en.wikipedia.org/wiki/Lightweight_Directory_Access_Protocol), [LDAP authentication](https://redis.io/docs/latest/operate/rs/security/access-control/ldap)\n\n\n\nThe time delay between when a command is issued and when a response is received. Redis is designed for low latency, typically operating in the sub-millisecond range.\n\nMore info: [Latency monitoring](https://redis.io/docs/latest/operate/oss_and_stack/management/optimization/latency-monitor), [Latency diagnosis](https://redis.io/docs/latest/operate/oss_and_stack/management/optimization/latency)"
    },
    {
      "id": "letter-m",
      "title": "M - O",
      "role": "content",
      "text": "[Node](https://redis.io/docs/latest/#redis-enterprise-nodes) that operates as the leader of a [cluster](https://redis.io/docs/latest/#cluster). Also known as the primary node.\n\nMore info: [Redis Enterprise cluster architecture](https://redis.io/docs/latest/operate/rs/clusters), [High availability](https://redis.io/docs/latest/#high-availability)\n\n\n\nDeciding when and where [shards](https://redis.io/docs/latest/#shard) will be moved if more network throughput, memory, or CPU resources are needed.\n\nMore info: [Database operations](https://redis.io/docs/latest/operate/rs/databases), [Cluster management](https://redis.io/docs/latest/operate/rs/clusters)\n\n\n\nProtocol that resolves hostnames to the IP addresses that do not include a local name server.\n\nMore info: [multicast DNS wikipedia](https://en.wikipedia.org/wiki/Multicast_DNS)\n\n\n\nA Redis extension that adds new commands, data types, and capabilities to Redis. Redis Enterprise includes several modules like RedisJSON, RedisSearch, RedisTimeSeries, and RedisBloom.\n\nMore info: [Redis modules](https://redis.io/docs/latest/operate/oss_and_stack/stack-with-enterprise), [Install modules](https://redis.io/docs/latest/operate/rs/installing-upgrading/modules)\n\n\n\nThe process of observing and tracking the performance, health, and behavior of Redis databases, clusters, and nodes using metrics and alerts.\n\nMore info: [Monitoring with metrics and alerts](https://redis.io/docs/latest/operate/rs/monitoring), [Metrics reference](https://redis.io/docs/latest/operate/rs/references/metrics)\n\n\n\nMethod of authenticating users with pieces of evidence of the user's identity. When MFA is enabled on Redis Cloud, users must enter their username, password, and an authentication code when logging in.\n\nMore info: [Multi-factor authentication](https://redis.io/docs/latest/operate/rc/security/access-control/multi-factor-authentication)\n\n\n\nAlso known as multi-master replication, Active-Active databases have multiple primary nodes (one on each participating cluster) to enable concurrent writes operations.\n\nMore info: [Multi-primary replication](https://redis.io/docs/latest/operate/rs/databases/active-active/#multi-primary-replication)\n\n\n\n\nAn abstraction used by Kubernetes to support multiple virtual clusters on the same physical cluster.\n\nMore info: [Namespaces](https://kubernetes.io/docs/concepts/overview/working-with-objects/namespaces/)\n\n\n\nWhen features are removed from our products, they're generally replaced by new features that provide a better experience, more functionality, improved security, and other benefits.\n\nTo provide a transition period, we mark older features as _deprecated_ when introducing replacement features.  This gives you time to adjust your deployments, apps, and processes to support the new features.  During this transition, the older features continue to work as a courtesy.\n\nEventually, older features are removed from the product.  When this happens, they're considered _obsolete_, partly because they can no longer be used.\n\nFor best results, we advise against relying on deprecated features for any length of time.\n\n\n\nOperators are software extensions to Kubernetes that make use of custom resources to manage applications and their components.\n\nMore info: [operator pattern](https://kubernetes.io/docs/concepts/extend-kubernetes/operator/)\n\n\n\nIf a member [Active-Active database](https://redis.io/docs/latest/#active-active) is in an out of memory situation, that member is marked \"inconsistent\" by Redis Enterprise Software, the member stops responding to user traffic, and the [syncer](https://redis.io/docs/latest/#syncer) initiates full reconciliation with other peers in the Active-Active database.\n\nMore info: [Active-Active database troubleshooting](https://redis.io/docs/latest/operate/rs/databases/active-active/syncer), [Memory management](https://redis.io/docs/latest/operate/rs/databases/memory-performance)"
    },
    {
      "id": "letter-p",
      "title": "P - Q",
      "role": "content",
      "text": "The ability to store data permanently to disk so that it survives server restarts. Redis supports RDB snapshots and AOF (Append-Only File) persistence methods.\n\nMore info: [Data persistence](https://redis.io/docs/latest/operate/oss_and_stack/management/persistence), [Redis Enterprise persistence](https://redis.io/docs/latest/operate/rs/databases/configure/database-persistence)\n\n\n\n[Clusters](https://redis.io/docs/latest/#cluster) participating in the [multi-primary replication](https://redis.io/docs/latest/#multi-primary-replication) of an [Active-Active database](https://redis.io/docs/latest/#active-active).\n\nMore info: [Active-Active geo-distributed Redis](https://redis.io/docs/latest/operate/rs/databases/active-active), [Create Active-Active database](https://redis.io/docs/latest/operate/rs/databases/active-active/create)\n\n\n\nA piece of storage in the cluster that has been provisioned by an administrator or dynamically provisioned using storage classes.\n\nMore info: [Persistent Volumes](https://kubernetes.io/docs/concepts/storage/persistent-volumes/)\n\n\n\nA request for storage by a user that serves as an abstract representation of PersistentVolume (PV) resources. PVCs consume PV resources and can request specific size and access modes.\n\nMore info: [Persistent Volumes](https://kubernetes.io/docs/concepts/storage/persistent-volumes/)\n\n\n\nThe smallest deployable units of computing that you can create and manage in Kubernetes. A pod represents a single instance of a running process in your cluster.\n\nMore info: [Pods](https://kubernetes.io/docs/concepts/workloads/pods/)\n\n\n\nDeciding where [shards](https://redis.io/docs/latest/#shard) will be created and placed within a [cluster](https://redis.io/docs/latest/#cluster).\n\nMore info: [Database operations](https://redis.io/docs/latest/operate/rs/databases), [Create databases](https://redis.io/docs/latest/operate/rs/databases/create)\n\n\n\nDetermines the number and location of active proxies tied to a single endpoint that receive incoming traffic for a database.\n\nFor more info, see [Proxy policy](https://redis.io/docs/latest/operate/rs/databases/configure/proxy-policy).\n\n\n\n[Node](https://redis.io/docs/latest/#redis-enterprise-nodes) provisioned only for [cluster](https://redis.io/docs/latest/#cluster) operations that can be elected as a [master node](https://redis.io/docs/latest/#master-node). The quorum node participates in the cluster quorum and must be explicitly assigned this role via the `rladmin` command.\n\nMore info: [Redis Enterprise cluster architecture](https://redis.io/docs/latest/operate/rs/clusters), [rladmin command reference](https://redis.io/docs/latest/operate/rs/references/cli-utilities/rladmin)"
    },
    {
      "id": "letter-r",
      "title": "R",
      "role": "content",
      "text": "A collection of Redis modules that extends Redis with modern data models and processing engines. Includes capabilities for document databases, graph databases, time series, and more.\n\nMore info: [Redis Stack](https://redis.io/docs/latest/operate/oss_and_stack/stack-with-enterprise), [Redis Stack features](https://redis.io/docs/latest/operate/oss_and_stack/stack-with-enterprise/enterprise-capabilities)\n\n\n\nRedis Enterprise feature that helps to ensure high availability in the event of a rack or zone failure. In the event of a rack or zone failure, the replicas and endpoints in the remaining racks/zones will be promoted.\n\nMore info: [Rack-zone awareness in Redis Enterprise Software](https://redis.io/docs/latest/operate/rs/clusters/configure/rack-zone-awareness)\n\n\n\n[Databases](https://redis.io/docs/latest/#redis-enterprise-database) using [replication](https://redis.io/docs/latest/#replication) or [Active-Active](https://redis.io/docs/latest/#active-active) maintain a backlog to synchronize the primary and replica [shards](https://redis.io/docs/latest/#shard).\n\nMore info: [Database replication](https://redis.io/docs/latest/operate/rs/databases/durability-ha/replication), [Active-Active databases](https://redis.io/docs/latest/operate/rs/databases/active-active)\n\n\n\nDistributing keys and their values among new [shards](https://redis.io/docs/latest/#shard) to optimize performance and resource utilization.\n\nMore info: [Database clustering](https://redis.io/docs/latest/operate/rs/databases/durability-ha/clustering), [Database operations](https://redis.io/docs/latest/operate/rs/databases)\n\n\n\nMoving [shards](https://redis.io/docs/latest/#shard) to [nodes](https://redis.io/docs/latest/#redis-enterprise-nodes) where more resources are available.\n\nMore info: [Database operations](https://redis.io/docs/latest/operate/rs/databases), [Cluster management](https://redis.io/docs/latest/operate/rs/clusters)\n\n\n\nThe cloud version of Redis Enterprise.\n\nMore info: [Redis Cloud](https://redis.io/docs/latest/operate/rc), [Redis Cloud quick start](https://redis.io/docs/latest/operate/rc/rc-quickstart)\n\n\n\nCollection of [Redis Enterprise nodes](https://redis.io/docs/latest/#redis-enterprise-nodes). A [cluster](https://redis.io/docs/latest/#cluster) pools system resources across nodes in the cluster and supports multi-tenant [database](https://redis.io/docs/latest/#redis-enterprise-database) instances.\n\nMore info: [Redis Enterprise cluster architecture](https://redis.io/docs/latest/operate/rs/clusters), [Cluster management](https://redis.io/docs/latest/operate/rs/clusters)\n\n\n\nLogical entity that manages your entire dataset across multiple [Redis instances](https://redis.io/docs/latest/#redis-instance). It segments the data into [shards](https://redis.io/docs/latest/#shard) and distributes them among [nodes](https://redis.io/docs/latest/#redis-enterprise-nodes).\n\nMore info: [Database operations](https://redis.io/docs/latest/operate/rs/databases), [Create databases](https://redis.io/docs/latest/operate/rs/databases/create)\n\n\n\nPhysical or virtual machines or containers that runs a collection of Redis Enterprise services within a [cluster](https://redis.io/docs/latest/#cluster).\n\nMore info: [Redis Enterprise cluster architecture](https://redis.io/docs/latest/operate/rs/clusters), [Install and setup](https://redis.io/docs/latest/operate/rs/installing-upgrading)\n\n\n\nThe on-premises version of Redis Enterprise.\n\nMore info: [Redis Enterprise Software](https://redis.io/docs/latest/operate/rs), [Install Redis Enterprise Software](https://redis.io/docs/latest/operate/rs/installing-upgrading)\n\n\n\nSingle-threaded Redis Open Source database. Redis OSS was renamed Redis Open Source with the Redis 8 in Redis Open Source release.\n\nMore info: [Redis Open Source](https://redis.io/docs/latest/operate/oss_and_stack), [Database clustering](https://redis.io/docs/latest/operate/rs/databases/durability-ha/clustering)\n\n\n\nPreviously known as Redis on Flash. Enables your Redis databases to span both RAM and dedicated flash memory (SSD). Auto Tiering manages the location of key values (RAM vs Flash) in the database via a LRU-based (least-recently-used) mechanism.\n\nMore info: [Auto Tiering](https://redis.io/docs/latest/operate/rs/databases/flash/), [Auto Tiering  quick start](https://redis.io/docs/latest/operate/rs/databases/flash/quickstart)\n\n\n\nHigh availability feature of Redis Enterprise Software. After a node failure, the cluster automatically migrates remaining replica shards to available nodes. Previously known as \"Slave HA\" or `slave_ha`.\n\nMore info: [High availability for replica shards](https://redis.io/docs/latest/operate/rs/databases/configure/replica-ha)\n\n\n\nThe Redis Enterprise implementation of active-passive database replication.\n\nMore info: [Replica Of\n](https://redis.io/docs/latest/operate/rs/databases/import-export/replica-of/)\n\n\n\nA ReplicaSet is a type of Kubernetes resource that (aims to) maintain a set of replica pods running at any given time.\n\nMore info: [ReplicaSet](https://kubernetes.io/docs/concepts/workloads/controllers/replicaset/)\n\n\n\n\nDatabase replication provides a mechanism to ensure high availability. When replication is enabled, your dataset is replicated to a replica shard,\nwhich is constantly synchronized with the primary shard. If the primary\nshard fails, an automatic failover happens and the replica shard is promoted.\n\nMore info: [Database replication](https://redis.io/docs/latest/operate/rs/databases/durability-ha/replication)\n\n\n\nKubernetes objects that grant the permissions defined in a role to a user or set of users, including service accounts.\n\nMore info: [RoleBinding and ClusterRoleBinding](https://kubernetes.io/docs/reference/access-authn-authz/rbac/#rolebinding-and-clusterrolebinding)\n\n\n\nA security approach that restricts system access to authorized users.\n\nMore info: [RBAC wikipedia](https://en.wikipedia.org/wiki/Role-based_access_control); [Database access control](https://redis.io/docs/latest/operate/rs/security/access-control); [Role-based access control](https://redis.io/docs/latest/operate/rc/security/access-control/data-access-control/role-based-access-control)\n\n\n\nKubernetes objects that contain rules representing a set of permissions. Roles define what actions can be performed on which resources.\n\nMore info: [Role and ClusterRole](https://kubernetes.io/docs/reference/access-authn-authz/rbac/#role-and-clusterrole)"
    },
    {
      "id": "letter-s",
      "title": "S",
      "role": "content",
      "text": "The ability to query and retrieve data using various search methods including full-text search, vector search, and secondary indexing. Redis provides search capabilities through its Search and Query features.\n\nMore info: [Redis Search](https://redis.io/docs/latest/develop/ai/search-and-query), [RedisSearch](https://redis.io/docs/latest/operate/oss_and_stack/stack-with-enterprise/search)\n\n\n\nCreating additional data structures to enable fast lookups on fields other than the primary key. Redis supports secondary indexing for JSON documents, hashes, and other data types.\n\nMore info: [Redis Search](https://redis.io/docs/latest/develop/ai/search-and-query), [Indexing concepts](https://redis.io/docs/latest/develop/ai/search-and-query/advanced-concepts)\n\n\n\nKubernetes term for object that stores sensitive information, such as passwords, OAuth tokens, and ssh keys.\n\nMore info: [Secrets](https://kubernetes.io/docs/concepts/configuration/secret/)\n\n\n\nProvides an identity for processes that run in a pod, allowing them to access the Kubernetes API and other resources.\n\nMore info: [Service Accounts](https://kubernetes.io/docs/concepts/security/service-accounts/)\n\n\n\nAn abstract way to expose an application running on a set of pods as a network service in Kubernetes.\n\nMore info: [Services](https://kubernetes.io/docs/concepts/services-networking/service/)\n\n\n\nRedis process that is part of the Redis clustered database.\n\nMore info: [Database clustering](https://redis.io/docs/latest/operate/rs/databases/durability-ha/clustering), [terminology](https://redis.io/docs/latest/operate/rs/references/terminology)\n\n\n\nTechnique that has been used to scale larger data storage and processing loads. Sharding take your data, partitions it into smaller pieces and then send the data to different locations depending on which partition the data has been assigned to. Related to [hash slots](https://redis.io/docs/latest/#hash-slot) and [shards](https://redis.io/docs/latest/#shard).\n\nMore info: [Database clustering](https://redis.io/docs/latest/operate/rs/databases/durability-ha/clustering), [Shards](https://redis.io/docs/latest/#shard)\n\n\n\nFramework for adding authentication support and data security to connection-based protocols via replaceable mechanisms.\n\nMore info: [SASL wikipedia](https://en.wikipedia.org/wiki/Simple_Authentication_and_Security_Layer)\n\n\n\nData persistence file that performs a data dump every one, six, or twelve hours. Used alongside [append-only file (AoF)](https://redis.io/docs/latest/#append-only-file-aof) for data persistence.\n\nMore info: [Data persistence](https://redis.io/docs/latest/operate/rs/databases/configure/database-persistence), [Append-only file (AoF)](https://redis.io/docs/latest/#append-only-file-aof)\n\n\n\nA way for administrators to describe the classes of storage they offer in Kubernetes, including different quality-of-service levels, backup policies, or arbitrary policies.\n\nMore info: [Storage Classes](https://kubernetes.io/docs/concepts/storage/storage-classes/)\n\n\n\nProcess on each node hosting an Active-Active database instance that synchronizes a backlog of operations between participating clusters.\n\nMore info: [Syncer process](https://redis.io/docs/latest/operate/rs/databases/active-active/syncer)"
    },
    {
      "id": "letter-t",
      "title": "T - Z",
      "role": "content",
      "text": "The number of operations or requests that can be processed per unit of time. Redis is designed for high throughput, capable of handling hundreds of thousands to millions of operations per second.\n\nMore info: [Redis benchmarks](https://redis.io/docs/latest/operate/oss_and_stack/management/optimization/benchmarks), [Performance optimization](https://redis.io/docs/latest/operate/oss_and_stack/management/optimization)\n\n\n\nA sequence of data points indexed in time order. Redis provides native time series support through RedisTimeSeries for storing and querying time-stamped data.\n\nMore info: [Time series data type](https://redis.io/docs/latest/develop/data-types/timeseries), [RedisTimeSeries](https://redis.io/docs/latest/operate/oss_and_stack/stack-with-enterprise/timeseries)\n\n\n\nA key that is logically deleted but stays in memory until it is collected by the garbage collector. Common in [Active-Active databases](https://redis.io/docs/latest/#active-active) during conflict resolution.\n\nMore info: [Active-Active database development](https://redis.io/docs/latest/operate/rs/databases/active-active/develop), [Conflict-free replicated data types (CRDT)](https://redis.io/docs/latest/#conflict-free-replicated-data-types-crdt)\n\n\n\nProtocols that provide communications security over a computer network.\n\nMore info: [TLS wikipedia](https://en.wikipedia.org/wiki/Transport_Layer_Security), [Cloud database TLS](https://redis.io/docs/latest/operate/rc/security/database-security/tls-ssl), [Redis Enterprise TLS](https://redis.io/docs/latest/operate/rs/security/encryption/tls)\n\n\n\nA search method that finds similar items by comparing high-dimensional vectors representing data features. Redis supports vector search for AI applications, machine learning, and similarity matching.\n\nMore info: [Vector search](https://redis.io/docs/latest/develop/ai/search-and-query/vectors), [Vector indexing](https://redis.io/docs/latest/develop/ai/search-and-query/query/vector-search)\n\n\n\nNetworking connection between two VPCs that enables you to route traffic between them using private IP addresses. Instances in either VPC can communicate with each other as if they are within the same network.\n\nMore info: [VPC wikipedia](https://en.wikipedia.org/wiki/Virtual_private_cloud), [Enable VPC peering](https://redis.io/docs/latest/operate/rc/security/vpc-peering)\n\n\n</dl>"
    }
  ],
  "examples": []
}