How to find out portal version, patch level information, components installed and system level information

From SLD 

To find out the desired information about the portal, you can use the System Landscape Directory.

If an SLD server exists in your NetWeaver landscape, enter the following URL to access the SLD:http://<sldserver>:<port>/sld 
If you're running a standalone portal, use the following URL to access the SLD informationhttp://<portalserver>:<port>/sld

From Portal 

If the SLD hasn't been set up or the above links won't work, you can get the desired information directly from the portal server.

1.To find out about the current version of portal you are working on.

2. The patch level information on the current portal.

3. The components installed on the current portal.

4. The system level information of the portal.

 All the above information can be gathered by accessing the URL below.

For System Information: http://<hostname>:portnumber/sap/monitoring/SystemInfo

For Component Information: http://<hostname>:portnumber/sap/monitoring/ComponentInfo

OR

http://<hostname>:portnumber/index.html and access the link System Information

NOTE : Ensure that the above links have to be accessed using the the right permissions. For example, the users J2EE_ADMIN or ADMINISTRATOR do have the right permissions. Use these permissions as a template.