**Remotely Upgrade Multiple Photon OS Machines With Lightwave Client and Photon Management Daemon Installed**

 
 After you have a configured the Photon Management Daemon (PMD) on multiple machines, you can remotely upgrade any installed package on these machines.
 
 Upgrade process uses `copenapi_cli` that is supported from both Lightwave and Photon Management Daemon. You can initiate the upgrade process from any machine that has Photon Management Daemon installed.   
 

 **Prerequisites**

 
 - Have an installed Lightwave server with configured domain controller on it.
 - Have installed Lightwave clients that are joined to the domain.
 - Have installed Photon Management Daemon on the clients.
 

 **Procedure**

 
 1. To initiate remote upgrade, log in to a Photon OS machine over SSH to install the Photon Management Daemon CLI.
 
 	`# tdnf install pmd-cli` 
 2. Edit the `copenapi_cli` spec files so that you can specify the machines you want to upgrade and credentials to be used.
 	1. Edit the `.netrc` file to specify machines to be upgraded and credentials for the PMD service.
 
 		`# vi ~/.netrc`  
 	3. In the file, enter the IP addresses for the machines and administrative credentials, save and close the file.
 
 		`# machine <IP-address> login <pmd-administrative-user> password <pmd-administrative user-password>`
 
 	1. (Optional) Get the location of the `restapispec.json` file.
 
 		`# cat ~/.copenapi`
 
 		This command returns `apispec=/root/restapispec.json` as path for the spec file.
  
 	3. Edit the `restapispec.json` file to enter the IP address of the machine to be upgraded.
 	
 		`# vi /root/restapispec.json`
 	4. Change the `host` value to the IP address or the hostname of the machine, leave the port number, and save and close the file.
 	
 		`"host":"<ip-address>:2081"` 
 	
 
 4. Initiate the upgrade, in this example of the `sed` package and wait for the command to complete.
 
 	Specify `-k` to force blind trust of certificates and `-n` to use the credentials from the `.netrc` file. 
 	`# copenapi_cli pkg update --packages sed -kn`
 
 5. (Optional) Verify that the package was upgraded successfully.
 	1. Log in to the machine that was upgraded over SSH.
 	2. List the installed version of the `sed` package.
 		
 		`# tdnf list installed sed`