IBM DS8000 manual Adding multipath volumes to iSeries using 5250 interface

￿2787 2 Gigabit Fibre Channel Disk Controller PCI-X

Both can be used for multipath and there is no requirement for all paths to use the same type of adapter. Both adapters can address up to 32 logical volumes. This does not change with multipath support. When deciding how many I/O adapters to use, your first priority should be to consider performance throughput of the IOA since this limit may be reached before the maximum number of logical units. See “Sizing guidelines” on page 396 for more information on sizing and performance guidelines.

		Volumes 1-24
		Volumes 25-48
Host Adapter 1	Host Adapter 2	IO Drawers and
IO Drawer	IO Drawer
IO Drawer	IO Drawer	Host Adapters
Host Adapter 3	Host Adapter 4
BUS a	BUS x	iSeries IO
FC IOA	FC IOA
BUS b	BUS y	Towers/Racks
FC IOA	FC IOA
		Logical connection

Figure B-24 Example of multipath with iSeries

Figure B-24shows an example where 48 logical volumes are configured in the DS8000. The first 24 of these are assigned via a host adapter in the top left I/O drawer in the DS8000 to a Fibre Channel I/O adapter in the first iSeries I/O tower or rack. The next 24 logical volumes are assigned via a host adapter in the lower left I/O drawer in the DS8000 to a Fibre Channel I/O adapter on a different BUS in the first iSeries I/O tower or rack. This would be a valid single path configuration.

To implement multipath, the first group of 24 logical volumes is also assigned to a Fibre Channel I/O adapter in the second iSeries I/O tower or rack via a host adapter in the lower right I/O drawer in the DS8000. The second group of 24 logical volumes is also assigned to a Fibre Channel I/O adapter on a different BUS in the second iSeries I/O tower or rack via a host adapter in the upper right I/O drawer.

Adding multipath volumes to iSeries using 5250 interface

If using the green screen 5250 interface, sign on to SST and perform the following steps as described in “Using 5250 interface” on page 376.

1.Option 3, Work with disk units.

2.Option 2, Work with disk configuration.

388DS8000 Series: Concepts and Architecture