The Storwize V5010 supports one SAS chain for each control enclosure, and up to 10  expansion enclosures can be attached to this chain. The node canister uses SAS port 1 for  expansion enclosures.  Always cable from the top down. Cabling from the bottom to the top is not supported. Figure 12-19 shows the SAS cabling on a Storwize V5010 with three attached expansion  enclosures. The Storwize V5020 supports one SAS chain for each control enclosure, and up to 10  expansion enclosures can be attached to this chain. The node canister uses SAS port 1 for  expansion enclosures. Always cable from the top down. Cabling from the bottom to the top is not supported. Figure 12-19 SAS expansion cabling on the Storwize V5010 Chapter 12. RAS, monitoring, and troubleshooting  637