If you want to just change the VM name, right click the VM in the inventory and select Rename.
For guest level host name change please login to the SHD Appliance as root user and execute following command
hostnamectl set-hostname NEW_HOSTNAME
Replace NEW_HOSTNAME with the name you want to set for the host.
Post this you may want to regenerate the SSL Certificates for SHD by running command : shd-config refreshcert
Restart Web Server with: systemctl restart nginx
-Thanks
Ram
