- Stop the FAST Search for SharePoint service.
- Stop the FAST Search for SharePoint Monitoring service.
- Move %FASTSEARCH%\data to the larger storage you have added.
- Run the following in a command prompt: mklink /j %FASTSEARCH%\data %NEW_LOCATION%\data
- Start the FAST Search for SharePoint Service.
Please note that it is not supported to have separate junction points data_fixml and data_index on an indexer-node instead of %FASTSEARCH%\data.