@mgulbranson  Thanks for your post. I think both ways work.  Here is the suggested system spec, but it for <1000 nodes, so if you have less nodes, 250GB should be fine.

@mgulbranson   It should be easy to just migrate the MongoDB data folder from one hard drive to another which had been mounted correctly. The steps should be 1.create the folders in new drive;2. Stop MongoDB service; 3.copy the data files/folder into the new folder; 4.grant the correct permission(user:group) to all the new data folders and files; 5. change the MongoDB config file to point to the new folder; 6. Start the MongoDB service and double check.