SAP Host Agent Upgrade 
SAP Host Agent is automatically installed during the installation of all new SAP system instances based on SAP NetWeaver 7.0 including Enhancement Package 2 or higher. As part of the SAP instance, SAP Host Agent is upgraded automatically when you patch or upgrade the SAP kernel. However, you can also upgrade SAP Host Agent independently from the SAP instance.
We recommend that you configure automated upgrade for SAP Host Agent. If required, you can also manually upgrade SAP Host Agent.