longhorn/docs/customized-default-setting.md

# Customized Default Setting

## Overview
During Longhorn system deployment, users can customize the default settings for Longhorn. e.g. specify `Create Default Disk With Node Labeled` and `Default Data Path` before starting the Longhorn system.

## Usage
### Note:
1. This default setting is only for Longhorn system that hasn't been deployed. And it has no impact on the existing Longhorn system.
2. The users should modify the settings for an existing Longhorn system via UI. 

### Via Rancher UI
[Cluster] -> System -> Apps -> Launch -> longhorn -> LONGHORN DEFAULT SETTINGS


### Via Longhorn deployment yaml file
1. Download the longhorn repo:
```
git clone https://github.com/longhorn/longhorn.git
```

2. Modify the config map named `longhorn-default-setting` in the yaml file `longhorn/deploy/longhorn.yaml`. For example:
```
---
apiVersion: v1
kind: ConfigMap
metadata:
  name: longhorn-default-setting
  namespace: longhorn-system
data:
  default-setting.yaml: |-
    backup-target: s3://backupbucket@us-east-1/backupstore
    backup-target-credential-secret: minio-secret 
    create-default-disk-labeled-nodes: true
    default-data-path: /var/lib/rancher/longhorn-example/
    replica-soft-anti-affinity: false
    storage-over-provisioning-percentage: 600
    storage-minimal-available-percentage: 15
    upgrade-checker: false
    default-replica-count: 2
    guaranteed-engine-cpu:
    default-longhorn-static-storage-class: longhorn-static-example
    backupstore-poll-interval: 500
    taint-toleration: key1=value1:NoSchedule; key2:NoExecute
---
```

### Via helm
1. Download the chart in the longhorn repo:
```
git clone https://github.com/longhorn/longhorn.git
```

2.1. Use helm command with `--set` flag to modify the default settings. 
For example:
```
helm install ./longhorn/chart --name longhorn --namespace longhorn-system --set defaultSettings.taintToleration="key1=value1:NoSchedule; key2:NoExecute"
```

2.2. Or directly modifying the default settings in the yaml file `longhorn/chart/values.yaml` then using helm command without `--set` to deploy Longhorn. 
For example:

In `longhorn/chart/values.yaml`:
```
defaultSettings:
  backupTarget: s3://backupbucket@us-east-1/backupstore
  backupTargetCredentialSecret: minio-secret 
  createDefaultDiskLabeledNodes: true
  defaultDataPath: /var/lib/rancher/longhorn-example/
  replicaSoftAntiAffinity: false
  storageOverProvisioningPercentage: 600
  storageMinimalAvailablePercentage: 15
  upgradeChecker: false
  defaultReplicaCount: 2
  guaranteedEngineCPU:
  defaultLonghornStaticStorageClass: longhorn-static-example
  backupstorePollInterval: 500
  taintToleration: key1=value1:NoSchedule; key2:NoExecute
```

Then use helm command:
```
helm install ./longhorn/chart --name longhorn --namespace longhorn-system
```

For more info about using helm, see: 
[Install-Longhorn-with-helm](../README.md#install-longhorn-with-helm)

## History
[Original feature request](https://github.com/longhorn/longhorn/issues/623)

Available since v0.6.0