This assumes you are familiar with the basic usage of the Gateway Migration Utility.

For security, the password being used can be encoded using the encode password command. 

/path/to/GatewayMigrationUtility.sh encodePassword –password yourPassword

The encode password command will produce a unique string of data, such as ryr45YH37v8_76vGnauf0.392RT13a2134Xxa. The unique string of data can be used as the secured password.

-password ryr45YH37v8_76vGnauf0.392RT13a2134Xxa