Update 2.deploy-connect-dashboard-ent.md (#2136)

docs-2.0/nebula-dashboard-ent/2.deploy-connect-dashboard-ent.md

@@ -23,12 +23,10 @@ Before deploying Dashboard Enterprise Edition, you must do a check of these:
   | 9200 | The port of the nebula-stats-exporter service. |
   | 9093 | The port of the Alertmanager service, used to receive Prometheus alerts and then send them to Dashboard.|
   | 9100   | The port of the node-exporter service. The node-exporter is automatically deployed on the target machine after a cluster is created or imported. It is used to collect the source information of machines in the cluster, including the CPU, memory, load, disk, and network.   |
-
-- The [license](11.dashboard-ent-license.md) is ready.
 
-  !!! enterpriseonly
+!!! enterpriseonly
 
-        The license is only available in the Enterprise Edition. To obtain the license, apply for [NebulaGraph Dashboard Free Trial](https://nebula-graph.io/visualization-tools-free-trial).
+    Dashboard Enterprise Edition uses the license to activate. To obtain the license, apply for [NebulaGraph Dashboard Free Trial](https://nebula-graph.io/visualization-tools-free-trial).
 
 ## Deploy Dashboard Enterprise Edition with TAR
 
@@ -130,6 +128,10 @@ Before deploying Dashboard Enterprise Edition, you must do a check of these:
 
 ## Deploy Dashboard Enterprise Edition with RPM 
 
+### Prerequisites
+
+The Linux version used is CentOS and lsof has been installed.
+
 ### Installation
 
 1. Download an RPM package.