text: **Number of paths:**For n + 1 redundancy, use the following number of paths: 
  
  (cid:2) With two HBA ports, zone HBA ports to Storwize V7000 ports 1:2 for a total of four 
  paths. 
  
  (cid:2) With four HBA ports, zone HBA ports to Storwize V7000 ports 1:1 for a total of four 
  paths. 
  
  (cid:2) Optional (n+2 redundancy): With four HBA ports, zone HBA ports to Storwize V7000 
  ports 1:2 for a total of eight paths. 
  
  Here, the term*HBA port*is used to describe the SCSI initiator and*Storwize V7000 port*
  to describe the SCSI target. 
  
  (cid:2) Maximum host paths per logical unit (LU) 
  
  For any volume, the number of paths through the SAN from the Storwize V7000 nodes to 
  a host must not exceed eight. For most configurations, four paths to an I/O Group are 
  sufficient. 
  
  **Important:**The maximum number of host paths per LUN must not exceed eight. 
  
  Another way to control the number of paths between hosts and the Storwize V7000 is to 
  use*port mask*. The port mask is an optional parameter of the**mkhost**and**chhost**
  commands. The port-mask configuration has no effect on iSCSI connections. 
  
  For each login between a host Fibre Channel port and node Fibre Channel port, the node 
  examines the port mask for the associated host object. It then determines whether access 
  is allowed (port mask bit for specific port is set) or denied (port mask bit is cleared). 
  
  If access is denied, the node responds to SCSI commands as though the HBA WWPN is 
  unknown. The port mask is 64 bits. Valid mask values range from all zeroes (no ports 
  enabled) to all ones (all ports enabled). For example, a mask of 0011 enables port 1 and 
  port 2. The default value is all 1s. 