Knowledge Base

• Two Fibre Channel host bus adapters (HBAs), such as QLogic or Emulex.
  
  
• Two fibre switches.
  
  
• Two storage processors (SPs): SPA and SPB. Each storage processor must have at least two ports connected to the SAN.

Use the following connection settings:

• HBA0 and HBA1 on each ESX Server connected to switches 1 and 2, respectively.
  
  
• Switch 1 connected to port 1 on SPA and to port 2 on SPB. Switch 2 connected to port 2 on SPA and to port 1 on SPB. Make sure to connect the SPA ports to a lower switch port number than that to which you connect the SPB ports. This allows SPA ports to be on the first paths seen by the host bus adapters in ESX Servers.

This configuration provides two paths from each HBA. LUNs must be owned by the storage processor to which the preferred and active paths are connected (in the above configuration, they should be owned by SPA). Please note that the above configuration assumes that the switches are not connected via Inter-Switch Link (ISL) in one fabric.

• For ESX Server 2.x
  
  vmkmultipath -q
  
  The output lists all known paths to each SAN LUN. The asterisk (*) indicates that the path is the current, active path, and the pound sign (#) indicates that this is the preferred path from the server to the LUN. For most SANs, the default policy in ESX Server 2.0.1 is fixed, however, in ESX Server 2.1 the default policy for most SANs is mru.
  
  
• For ESX Server 3.x
  
  
  esxcfg-mpath -l
  
  Example:
  
  Disk vmhba1:0:1 vml.0200070000600601609e9818000e5f8d7bb280dc11524149442035 /dev/sda (358400MB) has 4 paths and policy of Most Recently Used
   FC 12:0.0 2100001b3217fb99:2000001b3217fb99<->5006016030600cf2:50060160b0600cf2 vmhba1:3:7 Standby  preferred
   FC 12:0.0 2100001b3217fb99:2000001b3217fb99<->5006016a30600cf2:50060160b0600cf2 vmhba1:4:7 On active
   FC 14:0.0 2100001b32175698:2000001b32175698<->5006016230600cf2:50060160b0600cf2 vmhba2:3:7 Standby 
   FC 14:0.0 2100001b32175698:2000001b32175698<->5006016830600cf2:50060160b0600cf2 vmhba2:4:7 On

• For ESX Server 2.x - http://www.vmware.com/pdf/esx_SAN_guide.pdf
• For ESX Server 3.x - http://www.vmware.com/pdf/vi3_san_guide.pdf