Note:  At the time of this writing, two back-end storage systems were supported as  permanently directly attached: IBM DS8000 and IBM FlashSystem 900. For more  information, see this IBM Support web page. The suggested SAN configuration is based in a dual fabric solution. The ports on external  storage systems and the IBM Storwize V5030 ports must be evenly split between the two  fabrics to provide redundancy if one of the fabrics goes offline. Ports:  The IBM Storwize V5030 supports a maximum of 16 ports or WWPNs from an  externally virtualized storage system. Figure 11-1 shows an example of how to cable devices to the SAN. Refer to this example  as we describe the zoning. For this example, we used an IBM Storwize V3700 as our  external storage. Chapter 11. External storage virtualization  609 – Zone the external Storwize V3700 canister 1 port 2 with the Storwize V5030 canister 1  port 2 and canister 2 port 2 in the blue fabric. GLYPH<SM590000> Create an IBM Storwize V5030/external storage zone for each storage system to be  virtualized, as shown in the following examples: Figure 11-1 SAN cabling and zoning example GLYPH<SM590000> Ensure that the switches or directors are at the firmware levels that are supported by the  IBM Storwize V5030 and that the port login maximums that are listed in the restriction  document are not exceeded. For more information, search for “Configuration Limits and  Restrictions for IBM Storwize V5000” at  this IBM Knowledge Center web page. GLYPH<SM590000> After the IBM Storwize V5030 and external storage systems are connected to the SAN  fabrics, zoning on the switches must be configured. In each fabric, create a zone with the  four IBM Storwize V5030 worldwide port names (WWPNs), two from each node canister  with up to a maximum of eight WWPNs from each external storage system. 