raft: disallow ha_storage stanza when raft storage is used (#8707)

command/server.go

@@ -1144,6 +1144,11 @@ func (c *ServerCommand) Run(args []string) int {
 	// Initialize the separate HA storage backend, if it exists
 	var ok bool
 	if config.HAStorage != nil {
+		if config.Storage.Type == "raft" {
+			c.UI.Error("HA storage cannot be declared when Raft is the storage type")
+			return 1
+		}
+
 		// TODO: Remove when Raft can server as the ha_storage backend.
 		// See https://github.com/hashicorp/vault/issues/8206
 		if config.HAStorage.Type == "raft" {

website/pages/docs/configuration/storage/raft.mdx

@@ -36,6 +36,9 @@ cluster_addr = "http://127.0.0.1:8201"
 `cluster_addr` to indicate the address and port to be used for communication
 between the nodes in the Raft cluster.
 
+~> **Note:** When using the Raft storage backend, a separate `ha_storage`
+backend cannot be declared.
+
 ~> **Note:** Raft cannot be used as the configured `ha_storage` backend at this
 time. To use Raft for HA coordination users must also use Raft for storage.