# Amazon ElastiCache Redis Monitoring

## Overview

Amazon ElastiCache for Redis is a fully managed, in-memory caching service that supports real-time applications with sub-millisecond latency. It is commonly used for caching, session management, real-time analytics, and message brokering.

Applications Manager’s ElastiCache Redis monitoring tool provides visibility into the performance, memory utilization, replication health, and command-level statistics of your Redis cache nodes. Monitoring these metrics enables administrators to identify cache bottlenecks, optimize memory usage, and ensure high availability of their caching layer.

## Creating a new ElastiCache Redis monitor

To learn how to create a new ElastiCache Redis monitor, [refer here](https://www.manageengine.com/products/applications_manager/help/aws-monitoring-tools.html#NewMonitor).

## Monitored parameters

Go to the **Monitors Category View** by clicking the **Monitors** tab. Click on the **ElastiCache Redis** instance available under **Amazon** in the **Cloud Apps** section. Displayed is the ElastiCache Redis bulk configuration view distributed into three tabs:

- **Availability** tab shows the availability history for the past 24 hours or 30 days.
- **Performance** tab shows health status and events for the past 24 hours or 30 days.
- **List view** tab enables you to perform [bulk admin configurations](https://www.manageengine.com/products/applications_manager/help/bulk-config.html).

By clicking a monitor from the list, you’ll be taken to the Amazon ElastiCache Redis dashboard which includes the following tabs:

- [Performance Overview](#performance-overview)
- [Network & Replication](#network--replication)
- [Command Statistics](#command-statistics)
- [Configuration](#configuration)

### Performance Overview

| Parameter | Description |
|---|---|
| **CLUSTER INFORMATION** |  |
| Cache Status | The current status of the ElastiCache Redis cluster node. |
| Node Type | The instance type of the ElastiCache Redis cache node. |
| Engine Version | The version of the Redis engine running on the cache node. |
| Endpoint Address | The DNS hostname of the cache node endpoint. |
| Endpoint Port | The port number of the cache node endpoint. |
| Is Master | The status indicating whether the ElastiCache Redis node is the primary node of the current shard/cluster at the time of polling. |
| Save In Progress | The status indicating whether there is an ongoing background save on the ElastiCache Redis cache node at the time of polling. |
| **PERFORMANCE** |  |
| CPU Utilization | The average CPU Utilization of the ElastiCache Redis cache node at the time of polling (in %). |
| Engine CPU Utilization | The average Engine CPU Utilization dedicated to the Redis engine at the time of polling (in %). |
| Cache Hit Rate | The average Cache Hit Rate (percentage of successful read-only key lookups) on the ElastiCache Redis cache node between the poll interval (in %). |
| **DATABASE UTILIZATION** |  |
| Database Memory Utilization | The average Database Memory Utilization percentage of total memory in use on the ElastiCache Redis cluster at the time of polling (in %). |
| Database Memory Utilization (Evict) | The average Database Memory Utilization (Evict) percentage of total memory in use, counted for eviction policy decisions, on the ElastiCache Redis cluster at the time of polling (in %). |
| Database Capacity Utilization | The average Database Capacity Usage percentage of total data capacity in use on the ElastiCache Redis cluster at the time of polling (in %). |
| Database Capacity Utilization (Evict) | The average Database Capacity Utilization (Evict) percentage of total data capacity in use, excluding overhead and COB, on the ElastiCache Redis cluster at the time of polling (in %). |
| **CPU CREDITS** |  |
| CPU Credit Balance | The average CPU Credit Balance of the ElastiCache Redis cache node at the time of polling. |
| CPU Credit Usage | The average CPU Credit Usage of the ElastiCache Redis cache node at the time of polling. |
| **FREE MEMORY** |  |
| Free Memory | The average Freeable Memory available on the ElastiCache Redis cache node at the time of polling (in MB). |
| **SWAP USAGE** |  |
| Swap Usage | The average Swap Usage on the ElastiCache Redis cache node at the time of polling (in MB). |
| **CACHE DATA USED** |  |
| Cache Data Used | The average Cache Data Used (allocated by Redis for all purposes including dataset and buffers) on the ElastiCache Redis cache node at the time of polling (in MB). |
| **MEMORY FRAGMENTATION** |  |
| Active Defrag Hits | The total number of Active Defrag Hits (value reallocations per minute by the active defragmentation process) on the ElastiCache Redis cache node between the poll interval. |
| Memory Fragmentation Ratio | The average Memory Fragmentation Ratio of memory allocated by the OS to memory requested by Redis on the ElastiCache Redis cache node between the poll interval. |
| **CACHE PERFORMANCE** |  |
| Cache Hits | The total number of Cache Hits (successful read-only key lookups in the main dictionary) on the ElastiCache Redis cache node between the poll interval. |
| Cache Misses | The total number of Cache Misses (unsuccessful read-only key lookups in the main dictionary) on the ElastiCache Redis cache node between the poll interval. |
| **KEYS EVICTED** |  |
| Keys Evicted | The total number of Keys Evicted due to the maxmemory limit on the ElastiCache Redis cache node between the poll interval. |
| **KEY EXPIRATION EVENTS** |  |
| Key Expiration Events | The total number of Key Expiration Events on the ElastiCache Redis cache node between the poll interval. |
| **CURRENT ITEMS** |  |
| Current Items | The average number of Current Items in the ElastiCache Redis cache between the poll interval. |
| Current Volatile Items | The average number of Current Volatile Items (keys with a TTL set across all databases) in the ElastiCache Redis cache between the poll interval. |
| **DB0 TIME TO LIVE** |  |
| DB0 Time To Live | The average DB0 Time To Live for keys in DB0 of the ElastiCache Redis cache node between the poll interval (in ms). |
| **KEYS TRACKED** |  |
| Keys Tracked | The total number of Keys Tracked by Redis key tracking on the ElastiCache Redis cache node between the poll interval. |
| **CONNECTIONS** |  |
| Current Connections | The average number of Current Connections (client connections, excluding read replicas) on the ElastiCache Redis cache node between the poll interval. |
| New Connections | The average number of New Connections accepted by the ElastiCache Redis server between the poll interval. |
| **AUTHENTICATION & AUTHORIZATION FAILURES** |  |
| Authentication Failures | The average number of Authentication Failures (failed AUTH command attempts) on the ElastiCache Redis instance between the poll interval. |
| Command Authorization Failures | The average number of Command Authorization Failures (failed calls to run unpermitted commands) on the ElastiCache Redis cache node between the poll interval. |
| Key Authorization Failures | The average number of Key Authorization Failures (failed attempts to access unpermitted keys) on the ElastiCache Redis cache node between the poll interval. |
| Channel Authorization Failures | The average number of Channel Authorization Failures (failed attempts to access unpermitted channels) on the ElastiCache Redis cache node between the poll interval. |
| **IAM AUTHENTICATION** |  |
| IAM Authentication Expirations | The total number of IAM Authentication Expirations (expired IAM-authenticated connections) on the ElastiCache Redis cache node between the poll interval. |
| IAM Authentication Throttling | The total number of IAM Authentication Throttling events (throttled IAM-authenticated AUTH or HELLO requests) on the ElastiCache Redis cache node between the poll interval. |

### Network & Replication

| Parameter | Description |
|---|---|
| **PRIMARY LINK HEALTH STATUS** |  |
| Primary Link Health Status | The Primary Link Health Status of the connection to the primary node on the ElastiCache Redis cache node at the time of polling. |
| Traffic Management Active | The Traffic Management Active status indicating whether ElastiCache is actively managing traffic on the ElastiCache Redis cache node at the time of polling. |
| **REPLICATION LAG** |  |
| Replication Lag | The average Replication Lag (time in seconds the replica is behind the primary node) of the ElastiCache Redis cache node between the poll interval (in s). |
| **DATA REPLICATED** |  |
| Data Replicated | The average Data Replicated (data sent from the primary node to all replicas) on the ElastiCache Redis cache node between the poll interval (in MB). |
| **GLOBAL DATASTORE REPLICATION LAG** |  |
| Global Datastore Replication Lag | The average Global Datastore Replication Lag between the secondary Region primary node and the primary Region primary node on the ElastiCache Redis cache node between the poll interval (in s). |
| **NETWORK ALLOWANCE EXCEEDED** |  |
| Inbound Bandwidth Limit Exceeded | The average Inbound Bandwidth Limit Exceeded (packets shaped because inbound bandwidth exceeded the maximum) on the ElastiCache Redis cache node between the poll interval. |
| Outbound Bandwidth Limit Exceeded | The average Outbound Bandwidth Limit Exceeded (packets shaped because outbound bandwidth exceeded the maximum) on the ElastiCache Redis cache node between the poll interval. |
| Connection Limit Exceeded | The average Network Connection Tracking Allowance Exceeded on the ElastiCache Redis cache node between the poll interval. |
| Packet Rate Limit Exceeded | The average Network Packets Per Second Allowance Exceeded on the ElastiCache Redis cache node between the poll interval. |
| **NETWORK TRAFFIC** |  |
| Incoming Traffic | The rate of data the host has read from the network per minute on the ElastiCache Redis cache node between the poll interval (in MB/min). |
| Outgoing Traffic | The rate of data the host has written to the network per minute on the ElastiCache Redis cache node between the poll interval (in MB/min). |
| **NETWORK PACKETS** |  |
| Packets Received | The rate of packets received on all network interfaces per minute on the ElastiCache Redis cache node between the poll interval (in packets/min). |
| Packets Transmitted | The rate of packets sent on all network interfaces per minute on the ElastiCache Redis cache node between the poll interval (in packets/min). |
| **NETWORK PEAK THROUGHPUT** |  |
| Peak Incoming Traffic | The maximum amount of data received per second on the ElastiCache Redis cache node between the poll interval (in MB/s). |
| Peak Outgoing Traffic | The maximum amount of data sent per second on the ElastiCache Redis cache node between the poll interval (in MB/s). |
| **NETWORK PEAK PACKETS** |  |
| Peak Incoming Packets | The maximum number of packets received per second on the ElastiCache Redis cache node between the poll interval (in packets/s). |
| Peak Outgoing Packets | The maximum number of packets sent per second on the ElastiCache Redis cache node between the poll interval (in packets/s). |
| **DISK THROUGHPUT** |  |
| Disk Data Read | The rate of data read from disk per minute on the ElastiCache Redis cache node between the poll interval (in MB/min). |
| Disk Data Write | The rate of data written to disk per minute on the ElastiCache Redis cache node between the poll interval (in MB/min). |
| **DISK ITEMS** |  |
| Disk Items Read | The rate of items read from disk per minute on the ElastiCache Redis cache node between the poll interval (in items/min). |
| Disk Items Write | The rate of items written to disk per minute on the ElastiCache Redis cache node between the poll interval (in items/min). |

**Note:** **Network & Replication** tab metrics are disabled from data collection by default and mapped under performance polling as **Network & Replication**. To enable data collection, navigate to **Settings → Performance Polling**, select the **Optimize Data Collection** tab, choose **Amazon ElastiCache Redis** as the monitor type and **Network & Replication** as the metric name, then set the preferred time interval.

### Command Statistics

| Parameter | Description |
|---|---|
| **READ/WRITE COMMAND LATENCY** |  |
| Get Type commands Latency | The average Get Type commands Latency (read-only type commands) on the ElastiCache Redis cache node between the poll interval (in microseconds). |
| Set Type commands Latency | The average Set Type commands Latency (write type commands) on the ElastiCache Redis cache node between the poll interval (in microseconds). |
| Key Based commands Latency | The average Key Based commands Latency on the ElastiCache Redis cache node between the poll interval (in microseconds). |
| Non Key Type commands Latency | The average Non Key Type commands Latency on the ElastiCache Redis cache node between the poll interval (in microseconds). |
| **READ/WRITE COMMAND USAGE** |  |
| Get Type Cmds | The total number of Get Type commands (read-only type commands) on the ElastiCache Redis cache node between the poll interval. |
| Set Type Cmds | The total number of Set Type commands (write type commands) on the ElastiCache Redis cache node between the poll interval. |
| Key based commands | The total number of Key Based commands on the ElastiCache Redis cache node between the poll interval. |
| Non-Key based commands | The total number of Non Key Type commands on the ElastiCache Redis cache node between the poll interval. |
| **DATA STRUCTURE COMMAND LATENCY** |  |
| String Based commands Latency | The average String Based commands Latency on the ElastiCache Redis cache node between the poll interval (in microseconds). |
| Hash Based commands Latency | The average Hash Based commands Latency on the ElastiCache Redis cache node between the poll interval (in microseconds). |
| List Based commands Latency | The average List Based commands Latency on the ElastiCache Redis cache node between the poll interval (in microseconds). |
| Set Based commands Latency | The average Set Based commands Latency on the ElastiCache Redis cache node between the poll interval (in microseconds). |
| Sorted Set Based commands Latency | The average Sorted Set Based commands Latency on the ElastiCache Redis cache node between the poll interval (in microseconds). |
| Stream Based commands Latency | The average Stream Based commands Latency on the ElastiCache Redis cache node between the poll interval (in microseconds). |
| JSON Based commands Latency | The average JSON Based commands Latency on the ElastiCache Redis cache node between the poll interval (in microseconds). |
| HyperLogLog Based commands Latency | The average HyperLogLog Based commands Latency on the ElastiCache Redis cache node between the poll interval (in microseconds). |
| **DATA STRUCTURE COMMAND USAGE** |  |
| String based commands | The total number of String Based commands on the ElastiCache Redis cache node between the poll interval. |
| Hash based commands | The total number of Hash Based commands on the ElastiCache Redis cache node between the poll interval. |
| List based commands | The total number of List Based commands on the ElastiCache Redis cache node between the poll interval. |
| Set based commands | The total number of Set Based commands on the ElastiCache Redis cache node between the poll interval. |
| Sorted Set based commands | The total number of Sorted Set Based commands on the ElastiCache Redis cache node between the poll interval. |
| Stream based commands | The total number of Stream Based commands on the ElastiCache Redis cache node between the poll interval. |
| JSON based commands | The total number of JSON Based commands on the ElastiCache Redis cache node between the poll interval. |
| HyperLogLog based commands | The total number of HyperLogLog Based commands on the ElastiCache Redis cache node between the poll interval. |
| **UTILITY COMMAND LATENCY** |  |
| Cluster Based commands Latency | The average Cluster Based commands Latency on the ElastiCache Redis cache node between the poll interval (in microseconds). |
| Eval Based commands Latency | The average Eval Based commands Latency on the ElastiCache Redis cache node between the poll interval (in microseconds). |
| Geospatial Based commands Latency | The average Geospatial Based commands Latency on the ElastiCache Redis cache node between the poll interval (in microseconds). |
| Pub/Sub Based commands Latency | The average Pub/Sub Based commands Latency on the ElastiCache Redis cache node between the poll interval (in microseconds). |
| **UTILITY COMMAND USAGE** |  |
| Cluster based commands | The total number of Cluster Based commands on the ElastiCache Redis cache node between the poll interval. |
| Eval based commands | The total number of Eval Based commands on the ElastiCache Redis cache node between the poll interval. |
| Geospatial based commands | The total number of Geospatial Based commands on the ElastiCache Redis cache node between the poll interval. |
| Pub/Sub based commands | The total number of Pub/Sub Based commands on the ElastiCache Redis cache node between the poll interval. |
| **REQUEST LATENCY** |  |
| Successful Write Request Latency | The average Successful Write Request Latency on the ElastiCache Redis cache node between the poll interval (in microseconds). |
| Successful Read Request Latency | The average Successful Read Request Latency on the ElastiCache Redis cache node between the poll interval (in microseconds). |
| **FAILED COMMANDS** |  |
| Failed Commands | The total number of failed commands (Error Count) on the ElastiCache Redis cache node between the poll interval. |
| **SEARCH STATISTICS** |  |
| Search Indexes | The total number of Search Indexes created on the ElastiCache Redis cache node between the poll interval. |
| Search Indexed Documents | The total number of Search Indexed Documents (keys in all indexes) on the ElastiCache Redis cache node between the poll interval. |
| **SEARCH MEMORY USAGE** |  |
| Search Memory Used | The average Search Memory Used (data consumed in all search data structures) on the ElastiCache Redis cache node between the poll interval (in MB). |

**Note:** **Command Statistics** tab metrics are disabled from data collection by default and mapped under performance polling as **Command Statistics**. To enable data collection, navigate to **Settings → Performance Polling**, select the **Optimize Data Collection** tab, choose **Amazon ElastiCache Redis** as the monitor type and **Command Statistics** as the metric name, then set the preferred time interval.

### Configuration

| Parameter | Description |
|---|---|
| **CONFIGURATION** |  |
| Cache Cluster ID | The unique identifier for the cache cluster node. |
| Engine Name | The name of the cache engine used on the node. |
| Engine Version | The version of the Redis engine running on the cache node. |
| Node Type | The instance type of the ElastiCache Redis cache node. |
| Creation Time | The date and time when the cache cluster was created. |
| Endpoint Address | The DNS hostname of the cache node endpoint. |
| Endpoint Port | The port number of the cache node endpoint. |
| Availability Zone | The AWS Availability Zone in which the cache node was created. |
| Replication Group ID | The identifier of the replication group to which this cache cluster belongs. |
| Preferred Maintenance Window | The weekly time range during which system maintenance can occur. |
| Parameter Group | The name of the cache parameter group associated with this cluster. |
| Subnet Group | The name of the cache subnet group associated with this cluster. |
| Snapshot Retention Limit | The number of days for which ElastiCache retains automatic snapshots before deleting them (in days). |
| Snapshot Window | The daily time range during which ElastiCache takes daily snapshots. |
| **SECURITY CONFIGURATION** |  |
| Security Group | The VPC security group associated with the cache cluster. |
| Transit Encryption | Whether data is encrypted in transit between the client and the cache node. |
| At-Rest Encryption | Whether data stored on disk is encrypted at rest. |
| Auto Minor Version Upgrade | Whether auto minor engine version upgrade is enabled for the cache cluster. |