Specifications

v Your host system has disks or logical volumes that are located on an ESS that is
already in use.
v The disk or logical volumes are attached to the host system with two or more
SCSI interfaces.
v The IBM Subsystem Device Driver is installed and running properly.
Notes:
1. If you use the IBM Subsystem Device Driver for AIX, you cannot perform a
concurrent migration because it does not support the simultaneous
attachment to LUNs through SCSI and fibre-channel paths.
2. You cannot use the IBM Subsystem Device Driver with IBM NUMA-Q,
Hewlett-Packard, Sun, or Novell NetWare host systems.
v The host system has one or more fibre-channel adapters installed, including
feature code 3022.
v All appropriate software prerequisites, drivers, and program temporary fixes have
been implemented.
Perform the following steps to migrate disks or volumes using a concurrent method.
1. Test the connectivity on both SCSI paths.
2. Remove the disks from one of the SCSI ports on the ESS.
3. Assign the disks to the worldwide port name of one of the fibre-channel host
bus adapters.
4. Test the system to ensure that you have connectivity on the SCSI path and the
fibre-channel path.
5. Remove the disks from the second SCSI port on the ESS.
6. Assign the disks to the worldwide port name of the second fibre-channel host
bus adapter.
7. Test the system to ensure that you have connectivity on both fibre-channel
paths.
Appendix B. Migrating from SCSI to fibre-channel 167