Hi Dinesh
If the cluster has a job scheduler I would suggest configuring RSM and using a WB Mechanical "Remote Solve Process" to solve to (pointing to a queue on the cluster). Mechanical will then recognize that the needed up-stream static analysis files should be sent along with the modal analysis input file. And the modal analysis input file written to take out the paths since the needed files will be in the same MAPDL working directory at the time of the solve.
Alternatively the whole WB Project can be updated to the cluster queue via RSM. This way a round-trip of the static result files is saved.
Please show the cluster administrator the Ansys Help on RSM.
If the cluster does not have a job scheduler then you can manually edit the modal input file to take out the path(s) as needed. And then when submitting the modal job to the cluster included the necessary static analysis files. The MAPDL help on restarts and linear perturbation should be reviewed first.
 Mike