Changing Physical Disk Storage in IBM DB2 pureScale: A Practical Example A GPFS tiebreaker disk can be changed only when the DB2 pureScale cluster is in maintenance   mode. To monitor the progress of adding and removing disks and GPFS rebalancing, run the GPFS  mmdf   <file system> command. Changing the physical disk storage of GPFS file systems:  http://www.ibm.com/support/docview.wss?uid=swg21633330 GPFS mmdf command reference:  https://ibm.biz/BdrLeX Related information 8