*As part of the [deprecation timeline](https://github.com/helm/charts/#deprecation-timeline). We will move this to an official repository [here](https://github.com/DandyDeveloper/charts)*
Please make PRs / Issues here from now on
We will keep the changes in sync as best we can, but we will be notifying people to submit PRs here from now on instead. If you have any questions, feel free to get in touch with either of the maintainers.
[Redis](http://redis.io/) is an advanced key-value cache and store. It is often referred to as a data structure server since keys can contain strings, hashes, lists, sets, sorted sets, bitmaps and hyperloglogs.
This chart bootstraps a [Redis](https://redis.io) highly available master/slave statefulset in a [Kubernetes](http://kubernetes.io) cluster using the Helm package manager.
- PV provisioner support in the underlying infrastructure
## Upgrading the Chart
Please note that there have been a number of changes simplifying the redis management strategy (for better failover and elections) in the 3.x version of this chart. These changes allow the use of official [redis](https://hub.docker.com/_/redis/) images that do not require special RBAC or ServiceAccount roles. As a result when upgrading from version >=2.0.1 to >=3.0.0 of this chart, `Role`, `RoleBinding`, and `ServiceAccount` resources should be deleted manually.
Starting from version `4.x` HAProxy sidecar prometheus-exporter removed and replaced by the embedded [HAProxy metrics endpoint](https://github.com/haproxy/haproxy/tree/master/contrib/prometheus-exporter), as a result when upgrading from version 3.x to 4.x section `haproxy.exporter` should be removed and the `haproxy.metrics` need to be configured for fit your needs.
The command deploys Redis on the Kubernetes cluster in the default configuration. By default this chart install one master pod containing redis master container and sentinel container along with 2 redis slave pods each containing their own sentinel sidecars. The [configuration](#configuration) section lists the parameters that can be configured during installation.
> **Tip**: List all releases using `helm list`
## Uninstalling the Chart
To uninstall/delete the deployment:
```bash
$ helm delete <chart-name>
```
The command removes all the Kubernetes components associated with the chart and deletes the release.
## Configuration
The following table lists the configurable parameters of the Redis chart and their default values.
| `auth` | Enables or disables redis AUTH (Requires `redisPassword` to be set) | `false` |
| `redisPassword` | A password that configures a `requirepass` and `masterauth` in the conf parameters (Requires `auth: enabled`) | `` |
| `authKey` | The key holding the redis password in an existing secret. | `auth` |
| `existingSecret` | An existing secret containing a key defined by `authKey` that configures `requirepass` and `masterauth` in the conf parameters (Requires `auth: enabled`, cannot be used in conjunction with `.Values.redisPassword`) | `` |
| `nodeSelector` | Node labels for pod assignment | `{}` |
| `tolerations` | Toleration labels for pod assignment | `[]` |
| `hardAntiAffinity` | Whether the Redis server pods should be forced to run on separate nodes. | `true` |
| `additionalAffinities` | Additional affinities to add to the Redis server pods. | `{}` |
| `securityContext` | Security context to be added to the Redis server pods. | `{runAsUser: 1000, fsGroup: 1000, runAsNonRoot: true}` |
| `affinity` | Override all other affinity settings with a string. | `""` |
| `persistentVolume.size` | Size for the volume | 10Gi |
| `persistentVolume.annotations` | Annotations for the volume | `{}` |
| `persistentVolume.reclaimPolicy` | Method used to reclaim an obsoleted volume. `Delete` or `Retain` | `""` |
| `emptyDir` | Configuration of `emptyDir`, used only if persistentVolume is disabled and no hostPath specified | `{}` |
| `exporter.enabled` | If `true`, the prometheus exporter sidecar is enabled | `false` |
| `exporter.extraArgs` | Additional args for the exporter | `{}` |
| `exporter.script` | A custom custom Lua script that will be mounted to exporter for collection of custom metrics. Creates a ConfigMap and sets env var `REDIS_EXPORTER_SCRIPT`. | |
| `exporter.serviceMonitor.enabled` | Use servicemonitor from prometheus operator | `false` |
| `exporter.serviceMonitor.namespace` | Namespace the service monitor is created in | `default` |
| `exporter.serviceMonitor.interval` | Scrape interval, If not set, the Prometheus default scrape interval is used | `nil` |
| `exporter.serviceMonitor.telemetryPath` | Path to redis-exporter telemetry-path | `/metrics` |
| `exporter.serviceMonitor.labels` | Labels for the servicemonitor passed to Prometheus Operator | `{}` |
| `exporter.serviceMonitor.timeout` | How long until a scrape request times out. If not set, the Prometheus default scape timeout is used | `nil` |
| `haproxy.metrics.serviceMonitor.labels` | Labels for the HAProxy metrics servicemonitor passed to Prometheus Operator | `{}` |
| `haproxy.metrics.serviceMonitor.timeout` | How long until a scrape request times out. If not set, the Prometheus default scape timeout is used | `nil` |
| `haproxy.init.resources` | Extra init resources | `{}` |
Alternatively, a YAML file that specifies the values for the parameters can be provided while installing the chart. For example,
```bash
$ helm install -f values.yaml stable/redis-ha
```
> **Tip**: You can use the default [values.yaml](values.yaml)
## Custom Redis and Sentinel config options
This chart allows for most redis or sentinel config options to be passed as a key value pair through the `values.yaml` under `redis.config` and `sentinel.config`. See links below for all available options.
1. Some config options should be renamed by redis version，e.g.:
```
# In redis 5.x，see https://raw.githubusercontent.com/antirez/redis/5.0/redis.conf
min-replicas-to-write: 1
min-replicas-max-lag: 5
# In redis 4.x and redis 3.x，see https://raw.githubusercontent.com/antirez/redis/4.0/redis.conf and https://raw.githubusercontent.com/antirez/redis/3.0/redis.conf
Sentinel options supported must be in the the `sentinel <option> <master-group-name> <value>` format. For example, `sentinel down-after-milliseconds 30000` would be added to the `sentinel.config` section of the `values.yaml` as:
```yml
down-after-milliseconds: 30000
```
If more control is needed from either the redis or sentinel config then an entire config can be defined under `redis.customConfig` or `sentinel.customConfig`. Please note that these values will override any configuration options under their respective section. For example, if you define `sentinel.customConfig` then the `sentinel.config` is ignored.
Redis may require some changes in the kernel of the host machine to work as expected, in particular increasing the `somaxconn` value and disabling transparent huge pages.
To do so, you can set up a privileged initContainer with the `sysctlImage` config values, for example:
```
sysctlImage:
enabled: true
mountHostSys: true
command:
- /bin/sh
- -xc
- |-
sysctl -w net.core.somaxconn=10000
echo never > /host-sys/kernel/mm/transparent_hugepage/enabled
```
## HAProxy startup
When HAProxy is enabled, it will attempt to connect to each announce-service of each redis replica instance in its init container before starting.
It will fail if announce-service IP is not available fast enough (10 seconds max by announce-service).
A such case could happen if the orchestator is pending the nomination of redis pods.
Risk is limited because announce-service is using `publishNotReadyAddresses: true`, although, in such case, HAProxy pod will be rescheduled afterward by the orchestrator.
