Hi Harish,
First i would like to recommend SAP Note 1179929 - ST03N displays data from other systems after a system copy
Second please confirm below points:
1.Have you maintained TMS via 000 --> SE06,use option Database copy.If not please configure TMS first.
2.Have you imported the profiles by RZ10.
3.Remove the source server hostname form /etc/hosts,and add the entries of current system.
4. SM51 > goto > hostname buffer > reset > Entire System
Kindly perform
ST03N --> Expert Mode -->Collector and Performance DB --> Performance Database --> Workload Collector Database --> Contents
Double Click on 'Contents' --> on right pane Contents of the NW statistics Database will be shown --> Choose the Host/Instance which are not belonging to this current monitors and click on Delete Trash Icon.
Kindly refer JuniorSAP. Blogged to share: SAP Homogeneous Copy on UNIX Systems
Restart the system & check again.
Thanks,
Gaurav