Linux OS
/usr/lib/Acronis/RegisterAgentTool/RegisterAgent -o register -a http://192.168.1.100 -u [username] -p [userpass]
Windows OS
Open Command prompt and navigate to C:\Program Files\Acronis\RegisterAgentTool:
cd "%ProgramFiles%\Acronis\RegisterAgentTool"
Issue this command to register the client machine using account and password:
register_agent.exe -o register -a http://192.168.1.100 -u [username] -p [userpass]