Feature Flags

With feature flags, you can try out optional or experimental features, and enable legacy features that are being phased out.

To learn more about feature values and how to enable them, see Enabling Experimental Features.

Some feature flags require a restart of the Rancher container. Features that require a restart are marked in the Rancher UI.

The following is a list of feature flags available in Rancher. If you’ve upgraded from a previous Rancher version, you may see additional flags in the Rancher UI, such as proxy or dashboard (both xref:[discontinued]):

  • continuous-delivery: Allows Fleet GitOps to be disabled separately from Fleet. See Continuous Delivery. for more information.

  • fleet: The Rancher provisioning framework in v2.6 and later requires Fleet. The flag will be automatically enabled when you upgrade, even if you disabled this flag in an earlier version of Rancher. See Continuous Delivery with Fleet for more information.

  • harvester: Manages access to the Virtualization Management page, where users can navigate directly to Harvester clusters and access the Harvester UI. See Harvester Integration Overview for more information.

  • istio-virtual-service-ui: Enables a visual interface to create, read, update, and delete Istio virtual services and destination rules, which are Istio traffic management features.

  • legacy: Enables a set of features from 2.5.x and earlier, that are slowly being phased out in favor of newer implementations. These are a mix of deprecated features as well as features that will eventually be available to newer versions. This flag is disabled by default on new Rancher installations. If you’re upgrading from a previous version of Rancher, this flag is enabled.

  • multi-cluster-management: Allows multi-cluster provisioning and management of Kubernetes clusters. This flag can only be set at install time. It can’t be enabled or disabled later.

  • rke1-custom-node-cleanup: Enables cleanup of deleted RKE1 custom nodes. We recommend that you keep this flag enabled, to prevent removed nodes from attempting to rejoin the cluster.

  • rke2: Enables provisioning RKE2 clusters. This flag is enabled by default.

  • token-hashing: Enables token hashing. Once enabled, existing tokens will be hashed and all new tokens will be hashed automatically with the SHA256 algorithm. Once a token is hashed it can’t be undone. This flag can’t be disabled after its enabled. See API Tokens for more information.

  • uiextension: Enables UI extensions. This flag is enabled by default. Enabling or disabling the flag forces the Rancher pod to restart. The first time this flag is set to true, it creates a CRD and enables the controllers and endpoints necessary for the feature to work. If set to false, it disables the previously mentioned controllers and endpoints. Setting uiextension to false has no effect on the CRD — it does not create a CRD if it does not yet exist, nor does it delete the CRD if it already exists.

  • unsupported-storage-drivers: Enables types for storage providers and provisioners that aren’t enabled by default. See Allow Unsupported Storage Drivers for more information.

  • ui-sql-cache: Enables a SQLite-based cache for UI tables. See UI Server-Side Pagination for more information.

The following table shows the availability and default values for some feature flags in Rancher. Features marked "GA" are generally available:

Feature Flag Name Default Value Status Available As Of Additional Information

continuous-delivery

true

GA

v2.6.0

external-rules

v2.7.14: false, v2.8.5: true

Removed

v2.7.14, v2.8.5

This flag affected external RoleTemplate behavior. It is removed in Rancher v2.9.0 and later as the behavior is enabled by default.

fleet

true

Can no longer be disabled

v2.6.0

fleet

true

GA

v2.5.0

harvester

true

Experimental

v2.6.1

legacy

false for new installs, true for upgrades

GA

v2.6.0

rke1-custom-node-cleanup

true

GA

v2.6.0

rke2

true

Experimental

v2.6.0

token-hashing

false for new installs, true for upgrades

GA

v2.6.0

uiextension

true

GA

v2.9.0

ui-sql-cache

false

Highly experimental

v2.9.0