Using Standalone Log Viewer 
Use this predefined view if you want to monitor and view logs and traces on an AS Java that is not running. Two types of offline connections are available:
Remote Method Invocation (RMI) – a protocol supported by the Standalone Log Viewer server. You can use RMI if you want to view log records on SAP NetWeaver 7.0.
SAPHostControl – an SAP Web service you can use for viewing logs and traces on SAP NetWeaver 7.1 and higher.
Prerequisites
To view logs and traces on 7.0 systems, use the Standalone Log Viewer server.
To view logs and traces on 7.1 and higher system versions, the Web service SAP Instance Agent has to be up and running.
Procedure
Open the Log Viewer tool by choosing
SAP NetWeaver Administrator 
Problem management Logs and Traces Log Viewer 
.Choose
Show View General Standalone Log Viewer ..In the Remote Connection pane, choose Connect to host.
The following fields appear:
Field
Description
Connect to host
Enter the host name of the system you want to monitor. By default, the name of the host is localhost. If you want to monitor a different system, enter its host name.
On Port
Enter the port number of the system whose logs you want to monitor. Here are the default system ports:
For 7.0 systems, it is 26000.
For 7.1 and higher system versions, it is 5<instance_number>13.
Protocol
From the dropdown box, choose one of the two methods, respectively:
RMI
SAP Instance Agent
Choose Apply Connections.
All logs and traces that are registered on the relevant server appear.
Choose Show Advanced Filter to set a filter criterion.
You can apply various types of filtering log records for these views.
More information: Filtering Logs and Traces