Below is an excerpt from Microsoft Technet.
Installing Protection Agents Manually
You can install protection agents manually. To manually install a protection agent, use the command line options in the following procedure.
You can also install a protection agent independently using Microsoft Systems Management Server (SMS). To create an SMS package for the DPM protection agent, you must provide the following to the SMS administrator:
A share to the DpmAgentInstaller.exe and DpmAgentInstaller_AMD64.exe packages.
A list of servers on which you are installing the protection agents.
The name of the DPM server.
To silently install the protection agent, run DpmAgentInstaller.exe /q
To install a protection agent manually
On the computer on which you want to install the protection agent, we recommend that you map a network drive to the DPM server. For example, from the command prompt type net use Z: \\DPM1\c$.
On the protected computer, from the command prompt, change the directory (CD) to z:\Program Files\Microsoft DPM\DPM\Agents\RA\2.0.5820.0\i386 (if you have a 64-bit computer, use AM64), and then type DpmAgentInstaller.exe
On a 64-bit computer, type DPMAgentInstaller_amd64.exe
If you use the DPM server name in the command line, DPM installs the protection agent and configures the security permissions for the DPM server.
You can perform a non-interactive installation by specifying a /q parameter after the DpmAgentInstaller.exe command. For example, type DpmAgentInstaller.exe /q
Restart the protected server.
The following step is not required if you specified the DPM server in Step 1.
To complete the protection agent configuration for the appropriate DPM server and firewall settings, from the command prompt, type
SetDpmServer.exe –dpmServerName DPM01
Where DPM01 is the actual DPM server name.
On the DPM server, from the DPM Management Shell prompt, type Attach-ProductionServer.ps1
The password parameter is not required and we recommend that you do not provide it. DPM will prompt you for a password, which will not appear on the screen. However, you can provide the password if you want to use the script to install a protection agent on a large number of servers.
If you are attaching the protected computer on a different domain, you must specify the fully qualified domain name. For example, Computer1.Domain1.corp.microsoft.com, where Computer1 is the name of the protected computer, and Domain1.corp.microsoft.com is the domain to which you are attaching the computer.
The required configurations to protect the production computer are created. DPM Administrator Console will now display the production computer.