System Overview 
System Overview allows you to monitor AS Java systems on a cluster level online and offline. This function enables you to detect and resolve different system problems directly navigating to the relevant tool within SAP NetWeaver Administrator.
To access the online System Overview tool, open SAP NetWeaver Administrator and then choose 
Availability and Performance 
System Overview 
.
You can also use the quick link: http://<host>:<port>/nwa/?
To access the standalone System Overview tool, use the SAP Instance Agent.
Features
System Overview allows you to:
View and manage all user sessions.
More information: Managing User Sessions
Know the number of all user requests per minute
More information: Viewing Requests per Minute
Know the number of all user requests for processing.
More information: Administration of the Request Queue
View the state of both Message and Enqueue servers.
More information: Monitoring the Central Services
View the number of all started, failed, and restarted nodes.
More information: Viewing Started, Failed, and Restarted Nodes
Know the number of all failed components.
More information: Managing Failed Components
Monitor the queue loading and overflow.
More information: Monitoring the Queue Loading and Overflow
View the total number of connections, processes, and usage rate of the database connection.
More information: Viewing Database Connections
View the validity period of system licenses and certificates.
More information: Viewing Licenses and Certificates
View the average and maximum system memory consumption.
More information: Viewing Memory Consumption
View all active Web sessions.
More information: Viewing Active Sessions
View Error 500 and other system messages.
More information: Viewing HTTP Responses
Monitor the VM garbage collection ratio, released memory, and full garbage collection.
More information: Monitoring the VM Garbage Collection
View CPU usage and maximum and total system memory utilization of the operating system.
More information: Viewing CPU Usage and Memory Utilization
View the number of calls and traffic by the external systems.
More information: Viewing Response Time and External Systems
View all fatal and error messages.
More information: Viewing Logs
Note
The standalone System Overview allows you to perform proactive monitoring in case the system is stopped.
If you want to use System Overview in standalone mode, the tool starts exchanging the required data with SAP NetWeaver Administrator through the Web Dynpro FlashIsland.
More information: Implementing Adobe Flash Islands for Web Dynpro Java