VMware Ubuntu Guest Add Harddrive without Rebooting

Four steps to add a new hard-disk to a running Ubuntu virtualized session, using Vmware.

1. Add the new hard-disk to the Ubuntu vmware image using Vsphere or VMWare Server.
2. Ssh into ubuntu session and run
   “echo “- – -” > /sys/class/scsi_host/NUMBER/scan”
   NUMBER is the scsi host value.  It will not hurt rescanning a running host, so I simply keep incrementing till I reach a scsi host value that is not created in the system yet.
3. Do an “fdisk -l” and voila your new disk should be available.
4. Do what you want with it!  (Software Raid or create a new partition etc).