[Ubuntu] How to delete SWAP partition during Ubuntu install

When it complains a RAID device is still in use (typically SWAP). 

Step-by-step guide

  1. Alt+F2 (to bring up a console)
  2. Check the md label running for swap partition using 'ls -l /dev/md'
  3. Use the corresponding md# with 'swapoff /dev/md###'
  4. Go back to installer and delete the partition