The tool uses XCP RRD over XAPI to get necessary data.
You must attach all hosts.

XenServer host connectivity

Allow access from the XorMon host to all XenServer hosts port 443 (HTTPS)

Users access

Create user account on each XenServer host.
The user account on your XenServer host must be allowed to read data from commands such as xe …-data-source-query
The account should be assigned at least the Pool Admin role in XenServer's Role Based Access Control (RBAC).

• If your setup has RBAC configured, create user account xormon and assign it the Pool Admin role.
• If you are using XenServer Free edition or do not have RBAC configured, only root user has necessary privileges.

XorMon configuration

• Add device into configuration from the UI:
  Settings icon ➡ Device ➡ Seerver ➡ XenServer New ➡
  
  
• Run "Test" for configured device, it must show "OK"
  
  
• Wait about 1 hour, then reload the web browser, you should see it in XorMon UI