Monitoring | Administration

Introduction

Monitoring Redis is essential for maintaining the health and performance of your Redis instances. This tutorial covers various aspects of monitoring Redis from basic commands to advanced monitoring techniques. By the end of this tutorial, you will have a good understanding of how to keep track of your Redis server's performance and health.

Basic Monitoring Commands

Redis provides several built-in commands to monitor its status and performance. Below are some of the most useful commands:

INFO Command

The INFO command provides a wealth of information about the Redis server, including statistics and configuration settings.

Example:

INFO

# Server
redis_version:6.2.1
redis_git_sha1:00000000
redis_git_dirty:0
redis_build_id:5e3a7c8d7a15c51e
redis_mode:standalone
os:Linux 4.15.0-142-generic x86_64
arch_bits:64
multiplexing_api:epoll
gcc_version:7.5.0
process_id:1
run_id:8a6d1d1b9b1c4d2a8d1b9b1c4d2a8d1b
tcp_port:6379
uptime_in_seconds:86400
uptime_in_days:1
hz:10
configured_hz:10
lru_clock:12345678
executable:/data/redis-server
config_file:/data/redis.conf
...

MONITOR Command

The MONITOR command streams real-time information about the commands being processed by the Redis server. It is useful for debugging and understanding the workload on your Redis instance.

Example:

MONITOR

1633024800.000000 [0 127.0.0.1:6379] "SET" "key1" "value1"
1633024801.000000 [0 127.0.0.1:6379] "GET" "key1"
1633024802.000000 [0 127.0.0.1:6379] "DEL" "key1"

Advanced Monitoring Tools

In addition to built-in commands, there are advanced tools available for monitoring Redis. These tools provide more detailed insights and visualizations.

Redis Sentinel

Redis Sentinel provides high availability and monitoring for Redis. It can monitor multiple Redis instances and automatically failover if the master goes down.

Example Configuration:

sentinel monitor mymaster 127.0.0.1 6379 2
sentinel down-after-milliseconds mymaster 5000
sentinel failover-timeout mymaster 60000
sentinel parallel-syncs mymaster 1

Redis Exporter for Prometheus

Redis Exporter is a Prometheus exporter for Redis metrics. It allows you to collect and visualize Redis metrics using Prometheus and Grafana.

Example Command to Start Redis Exporter:

./redis_exporter -redis.addr=redis://localhost:6379

Setting Up Alerts

Setting up alerts is crucial for proactive monitoring. You can use tools like Prometheus Alertmanager to create alerts based on Redis metrics.

Example Alert Rule:

alert: RedisInstanceDown
expr: up{job="redis"} == 0
for: 5m
labels:
  severity: critical
annotations:
  summary: "Redis instance is down"
  description: "Redis instance {{ $labels.instance }} has been down for more than 5 minutes."

Conclusion

Monitoring Redis is a continuous process that involves using built-in commands, advanced tools, and setting up alerts. This tutorial covered the basic and advanced aspects of monitoring Redis, providing you with the necessary knowledge to maintain a healthy and performant Redis instance.

Administration: Monitoring Redis