Prometheus Redis Metrics Exporter

Prometheus exporter for Redis metrics.
Supports Redis 2.x, 3.x, 4.x, 5.x, and 6.x

Building and running the exporter

Build and run locally

git clone https://github.com/oliver006/redis_exporter.git
cd redis_exporter
go build .
./redis_exporter --version

Pre-build binaries

For pre-built binaries please take a look at the releases.

Upgrading from 0.x to 1.x

PR #256 introduced breaking changes which were released as version v1.0.0.

If you only scrape one Redis instance and use command line flags --redis.address and --redis.password then you're most probably not affected. Otherwise, please see PR #256 and this README for more information.

Basic Prometheus Configuration

Add a block to the scrape_configs of your prometheus.yml config file:

scrape_configs:
  - job_name: redis_exporter
    static_configs:
    - targets: ['<<REDIS-EXPORTER-HOSTNAME>>:9121']

and adjust the host name accordingly.

Kubernetes SD configurations

To have instances in the drop-down as human readable names rather than IPs, it is suggested to use instance relabelling.

For example, if the metrics are being scraped via the pod role, one could add:

          - source_labels: [__meta_kubernetes_pod_name]
            action: replace
            target_label: instance
            regex: (.*redis.*)

as a relabel config to the corresponding scrape config. As per the regex value, only pods with "redis" in their name will be relabelled as such.

Similar approaches can be taken with other role types depending on how scrape targets are retrieved.

Prometheus Configuration to Scrape Multiple Redis Hosts

Run the exporter with the command line flag --redis.addr= so it won't try to access the local instance every time the /metrics endpoint is scraped.

scrape_configs:
  ## config for the multiple Redis targets that the exporter will scrape
  - job_name: 'redis_exporter_targets'
    static_configs:
      - targets:
        - redis://first-redis-host:6379
        - redis://second-redis-host:6379
        - redis://second-redis-host:6380
        - redis://second-redis-host:6381
    metrics_path: /scrape
    relabel_configs:
      - source_labels: [__address__]
        target_label: __param_target
      - source_labels: [__param_target]
        target_label: instance
      - target_label: __address__
        replacement: <<REDIS-EXPORTER-HOSTNAME>>:9121

  ## config for scraping the exporter itself
  - job_name: 'redis_exporter'
    static_configs:
      - targets:
        - <<REDIS-EXPORTER-HOSTNAME>>:9121

The Redis instances are listed under targets, the Redis exporter hostname is configured via the last relabel_config rule.
If authentication is needed for the Redis instances then you can set the password via the --redis.password command line option of the exporter (this means you can currently only use one password across the instances you try to scrape this way. Use several exporters if this is a problem).
You can also use a json file to supply multiple targets by using file_sd_configs like so:

scrape_configs:
  - job_name: 'redis_exporter_targets'
    file_sd_configs:
      - files:
        - targets-redis-instances.json
    metrics_path: /scrape
    relabel_configs:
      - source_labels: [__address__]
        target_label: __param_target
      - source_labels: [__param_target]
        target_label: instance
      - target_label: __address__
        replacement: <<REDIS-EXPORTER-HOSTNAME>>:9121

  ## config for scraping the exporter itself
  - job_name: 'redis_exporter'
    static_configs:
      - targets:
        - <<REDIS-EXPORTER-HOSTNAME>>:9121

The targets-redis-instances.json should look something like this:

[
  {
    "targets": [ "redis://redis-host-01:6379", "redis://redis-host-02:6379"],
    "labels": { }
  }
]

Prometheus uses file watches and all changes to the json file are applied immediately.

Command line flags

Name	Environment Variable Name	Description
redis.addr	REDIS_ADDR	Address of the Redis instance, defaults to redis://localhost:6379.
redis.user	REDIS_USER	User name to use for authentication (Redis ACL for Redis 6.0 and newer).
redis.password	REDIS_PASSWORD	Password of the Redis instance, defaults to "" (no password).
check-keys	REDIS_EXPORTER_CHECK_KEYS	Comma separated list of key patterns to export value and length/size, eg: db3=user_count will export key user_count from db 3. db defaults to 0 if omitted. The key patterns specified with this flag will be found using SCAN. Use this option if you need glob pattern matching; check-single-keys is faster for non-pattern keys. Warning: using --check-keys to match a very large number of keys can slow down the exporter to the point where it doesn't finish scraping the redis instance.
check-single-keys	REDIS_EXPORTER_CHECK_SINGLE_KEYS	Comma separated list of keys to export value and length/size, eg: db3=user_count will export key user_count from db 3. db defaults to 0 if omitted. The keys specified with this flag will be looked up directly without any glob pattern matching. Use this option if you don't need glob pattern matching; it is faster than check-keys.
script	REDIS_EXPORTER_SCRIPT	Path to Redis Lua script for gathering extra metrics.
debug	REDIS_EXPORTER_DEBUG	Verbose debug output
log-format	REDIS_EXPORTER_LOG_FORMAT	Log format, valid options are txt (default) and json.
namespace	REDIS_EXPORTER_NAMESPACE	Namespace for the metrics, defaults to redis.
connection-timeout	REDIS_EXPORTER_CONNECTION_TIMEOUT	Timeout for connection to Redis instance, defaults to "15s" (in Golang duration format)
web.listen-address	REDIS_EXPORTER_WEB_LISTEN_ADDRESS	Address to listen on for web interface and telemetry, defaults to 0.0.0.0:9121.
web.telemetry-path	REDIS_EXPORTER_WEB_TELEMETRY_PATH	Path under which to expose metrics, defaults to /metrics.
redis-only-metrics	REDIS_EXPORTER_REDIS_ONLY_METRICS	Whether to also export go runtime metrics, defaults to false.
include-system-metrics	REDIS_EXPORTER_INCL_SYSTEM_METRICS	Whether to include system metrics like total_system_memory_bytes, defaults to false.
ping-on-connect	REDIS_EXPORTER_PING_ON_CONNECT	Whether to ping the redis instance after connecting and record the duration as a metric, defaults to false.
is-tile38	REDIS_EXPORTER_IS_TILE38	Whether to scrape Tile38 specific metrics, defaults to false.
export-client-list	REDIS_EXPORTER_EXPORT_CLIENT_LIST	Whether to scrape Client List specific metrics, defaults to false.
skip-tls-verification	REDIS_EXPORTER_SKIP_TLS_VERIFICATION	Whether to to skip TLS verification
tls-client-key-file	REDIS_EXPORTER_TLS_CLIENT_KEY_FILE	Name of the client key file (including full path) if the server requires TLS client authentication
tls-client-cert-file	REDIS_EXPORTER_TLS_CLIENT_CERT_FILE	Name the client cert file (including full path) if the server requires TLS client authentication
tls-ca-cert-file	REDIS_EXPORTER_TLS_CA_CERT_FILE	Name of the CA certificate file (including full path) if the server requires TLS client authentication
set-client-name	REDIS_EXPORTER_SET_CLIENT_NAME	Whether to set client name to redis_exporter, defaults to true.

Redis instance addresses can be tcp addresses: redis://localhost:6379, redis.example.com:6379 or e.g. unix sockets: unix:///tmp/redis.sock.
SSL is supported by using the rediss:// schema, for example: rediss://azure-ssl-enabled-host.redis.cache.windows.net:6380 (note that the port is required when connecting to a non-standard 6379 port, e.g. with Azure Redis instances).
Password-protected instances can be accessed by using the URI format including a password: redis://h:<<PASSWORD>>@<<HOSTNAME>>:<<PORT>>

Command line settings take precedence over any configurations provided by the environment variables.

Run via Docker

The latest release is automatically published to the Docker registry.

You can run it like this:

docker run -d --name redis_exporter -p 9121:9121 oliver006/redis_exporter

The latest docker image contains only the exporter binary. If, e.g. for debugging purposes, you need the exporter running in an image that has a shell, etc then you can run the alpine image:

docker run -d --name redis_exporter -p 9121:9121 oliver006/redis_exporter:alpine

If you try to access a Redis instance running on the host node, you'll need to add --network host so the redis_exporter container can access it:

docker run -d --name redis_exporter --network host oliver006/redis_exporter

Run on Kubernetes

Here is an example Kubernetes deployment configuration for how to deploy the redis_exporter as a sidecar to a Redis instance.

What's exported

Most items from the INFO command are exported, see Redis documentation for details.
In addition, for every database there are metrics for total keys, expiring keys and the average TTL for keys in the database.
You can also export values of keys if they're in numeric format by using the -check-keys flag. The exporter will also export the size (or, depending on the data type, the length) of the key. This can be used to export the number of elements in (sorted) sets, hashes, lists, streams, etc.

If you require custom metric collection, you can provide a Redis Lua script using the -script flag. An example can be found in the contrib folder.

The redis_memory_max_bytes metric

The metric redis_memory_max_bytes will show the maximum number of bytes Redis can use.
It is zero if no memory limit is set for the Redis instance you're scraping (this is the default setting for Redis).
You can confirm that's the case by checking if the metric redis_config_maxmemory is zero or by connecting to the Redis instance via redis-cli and running the command CONFIG GET MAXMEMORY.

What it looks like

Example Grafana screenshots:

Grafana dashboard is available on grafana.com and/or github.com.

Viewing multiple Redis simultaneously

If running Redis Sentinel, it may be desirable to view the metrics of the various cluster members simultaneously. For this reason the dashboard's drop down is of the multi-value type, allowing for the selection of multiple Redis. Please note that there is a caveat; the single stat panels up top namely uptime, total memory use and clients do not function upon viewing multiple Redis.

Communal effort

Open an issue or PR if you have more suggestions, questions or ideas about what to add.