Redis

Plugin: go.d.plugin Module: redis

Overview

This collector monitors the health and performance of Redis servers and collects general statistics, CPU and memory consumption, replication information, command statistics, and more.

It connects to the Redis instance via a TCP or UNIX socket and executes the following commands:

• INFO ALL
• PING

This collector is supported on all platforms.

This collector supports collecting metrics from multiple instances of this integration, including remote instances.

Default Behavior

Auto-Detection

By default, it detects instances running on localhost by attempting to connect using known Redis TCP and UNIX sockets:

• 127.0.0.1:6379
• /tmp/redis.sock
• /var/run/redis/redis.sock
• /var/lib/redis/redis.sock

Limits

The default configuration for this integration does not impose any limits on data collection.

Performance Impact

The default configuration for this integration is not expected to impose a significant performance impact on the system.

Metrics

Metrics grouped by scope.

The scope defines the instance that the metric belongs to. An instance is uniquely identified by a set of labels.

Per Redis instance

These metrics refer to the entire monitored application.

This scope has no labels.

Metrics:

Metric	Dimensions	Unit
redis.connections	accepted, rejected	connections/s
redis.clients	connected, blocked, tracking, in_timeout_table	clients
redis.ping_latency	min, max, avg	seconds
redis.commands	processes	commands/s
redis.keyspace_lookup_hit_rate	lookup_hit_rate	percentage
redis.memory	max, used, rss, peak, dataset, lua, scripts	bytes
redis.mem_fragmentation_ratio	mem_fragmentation	ratio
redis.key_eviction_events	evicted	keys/s
redis.net	received, sent	kilobits/s
redis.rdb_changes	changes	operations
redis.bgsave_now	current_bgsave_time	seconds
redis.bgsave_health	last_bgsave	status
redis.bgsave_last_rdb_save_since_time	last_bgsave_time	seconds
redis.aof_file_size	current, base	bytes
redis.commands_calls	a dimension per command	calls
redis.commands_usec	a dimension per command	microseconds
redis.commands_usec_per_sec	a dimension per command	microseconds/s
redis.key_expiration_events	expired	keys/s
redis.database_keys	a dimension per database	keys
redis.database_expires_keys	a dimension per database	keys
redis.connected_replicas	connected	replicas
redis.master_link_status	up, down	status
redis.master_last_io_since_time	time	seconds
redis.master_link_down_since_time	time	seconds
redis.uptime	uptime	seconds

Alerts

The following alerts are available:

Alert name	On metric	Description
redis_connections_rejected	redis.connections	connections rejected because of maxclients limit in the last minute
redis_bgsave_slow	redis.bgsave_now	duration of the on-going RDB save operation
redis_bgsave_broken	redis.bgsave_health	status of the last RDB save operation (0: ok, 1: error)
redis_master_link_down	redis.master_link_down_since_time	time elapsed since the link between master and slave is down

Setup

Prerequisites

No action required.

Configuration

File

The configuration file name for this integration is go.d/redis.conf.

You can edit the configuration file using the edit-config script from the Netdata config directory.

cd /etc/netdata 2>/dev/null || cd /opt/netdata/etc/netdata
sudo ./edit-config go.d/redis.conf

Options

The following options can be defined globally: update_every, autodetection_retry.

Config options

Name	Description	Default	Required
update_every	Data collection frequency.	5	no
autodetection_retry	Recheck interval in seconds. Zero means no recheck will be scheduled.	0	no
address	Redis server address.	redis://@localhost:6379	yes
timeout	Dial (establishing new connections), read (socket reads) and write (socket writes) timeout in seconds.	1	no
username	Username used for authentication.		no
password	Password used for authentication.		no
tls_skip_verify	Server certificate chain and hostname validation policy. Controls whether the client performs this check.	no	no
tls_ca	Certificate authority that client use when verifying server certificates.		no
tls_cert	Client tls certificate.		no
tls_key	Client tls key.		no

Examples

TCP socket

An example configuration.

Config

jobs:
  - name: local
    address: 'redis://@127.0.0.1:6379'

Unix socket

An example configuration.

Config

jobs:
  - name: local
    address: 'unix://@/tmp/redis.sock'

TCP socket with password

An example configuration.

Config

jobs:
  - name: local
    address: 'redis://:[email protected]:6379'

Multi-instance

Note: When you define multiple jobs, their names must be unique.

Local and remote instances.

Config

jobs:
  - name: local
    address: 'redis://:[email protected]:6379'

  - name: remote
    address: 'redis://user:[email protected]:6379'

Troubleshooting

Debug Mode

Important: Debug mode is not supported for data collection jobs created via the UI using the Dyncfg feature.

To troubleshoot issues with the redis collector, run the go.d.plugin with the debug option enabled. The output should give you clues as to why the collector isn't working.

• Navigate to the plugins.d directory, usually at /usr/libexec/netdata/plugins.d/. If that's not the case on your system, open netdata.conf and look for the plugins setting under [directories].

  cd /usr/libexec/netdata/plugins.d/

• Switch to the netdata user.

  sudo -u netdata -s

• Run the go.d.plugin to debug the collector:

  ./go.d.plugin -d -m redis

Getting Logs

If you're encountering problems with the redis collector, follow these steps to retrieve logs and identify potential issues:

• Run the command specific to your system (systemd, non-systemd, or Docker container).
• Examine the output for any warnings or error messages that might indicate issues. These messages should provide clues about the root cause of the problem.

System with systemd

Use the following command to view logs generated since the last Netdata service restart:

journalctl _SYSTEMD_INVOCATION_ID="$(systemctl show --value --property=InvocationID netdata)" --namespace=netdata --grep redis

System without systemd

Locate the collector log file, typically at /var/log/netdata/collector.log, and use grep to filter for collector's name:

grep redis /var/log/netdata/collector.log

Note: This method shows logs from all restarts. Focus on the latest entries for troubleshooting current issues.

Docker Container

If your Netdata runs in a Docker container named "netdata" (replace if different), use this command:

docker logs netdata 2>&1 | grep redis