feat: Add ability to enable Longhorn V2 Data Engine

Related issue: harvester/harvester#5274

Signed-off-by: Tim Serong <tserong@suse.com>

pkg/harvester/config/settings.js

@@ -31,7 +31,8 @@ export const HCI_SETTING = {
   VM_TERMINATION_PERIOD:                  'default-vm-termination-grace-period-seconds',
   NTP_SERVERS:                            'ntp-servers',
   AUTO_ROTATE_RKE2_CERTS:                 'auto-rotate-rke2-certs',
-  KUBECONFIG_DEFAULT_TOKEN_TTL_MINUTES:   'kubeconfig-default-token-ttl-minutes'
+  KUBECONFIG_DEFAULT_TOKEN_TTL_MINUTES:   'kubeconfig-default-token-ttl-minutes',
+  LONGHORN_V2_DATA_ENGINE_ENABLED:        'longhorn-v2-data-engine-enabled',
 };
 
 export const HCI_ALLOWED_SETTINGS = {
@@ -83,6 +84,7 @@ export const HCI_ALLOWED_SETTINGS = {
     kind: 'json', from: 'import', canReset: true
   },
   [HCI_SETTING.KUBECONFIG_DEFAULT_TOKEN_TTL_MINUTES]: {},
+  [HCI_SETTING.LONGHORN_V2_DATA_ENGINE_ENABLED]:      { kind: 'boolean' },
 };
 
 export const HCI_SINGLE_CLUSTER_ALLOWED_SETTING = {

pkg/harvester/l10n/en-us.yaml

@@ -1370,6 +1370,7 @@ advancedSettings:
     'harv-ntp-servers': Configure NTP server. You can configure multiple IPv4 addresses or host addresses.
     'harv-auto-rotate-rke2-certs': The certificate rotation mechanism relies on Rancher. Harvester will automatically update certificates generation to trigger rotation.
     'harv-kubeconfig-default-token-ttl-minutes': 'TTL (in minutes) applied on Harvester admin kubeconfig files. Default is 0, which means to never expire.'
+    'harv-longhorn-v2-data-engine-enabled': 'Enable the Longhorn V2 data engine. Default is false. <ul><li>Changing this setting will restart RKE2 on all nodes. This will not affect running VM workloads.</li><li>If you see "not enough hugepages-2Mi capacity" errors when enabling this setting, wait a minute for the error to clear. If the error remains, reboot the affected node.</li><li>WARNING: THIS IS A PREVIEW FEATURE</li></ul>'
 
 typeLabel:
   kubevirt.io.virtualmachine: |-