HP Surestore Disk Array 12h System Administrator's Guide for HP-UX, MPE, and W - Page 20

HP-UX Using the HP-UX System Administration Manager Selecting Hardware Paths on HP-UX 10.20 Selecting Hardware Paths on HP-UX 10.20 On dual controller disk arrays, each controller provides a separate hardware path to the disk array. The host identifies one of these paths as the default hardware path and will use the default as the primary data path for access to the LUNs created on the disk array. To improve disk array performance, the paths to the LUNs on the disk array should be shared by both controllers. Dividing the primary data paths across both controllers balances the I/O load and optimizes disk array performance. The primary hardware path to each LUN is established when adding the LUN to a volume group. On HP-UX 10.01 and 10.10, both controller hardware paths are displayed on the Disk Devices windows. The hardware path for a LUN is established by selecting the appropriate path. On HP-UX 10.20 and later, only the primary controller hardware path is displayed in the Disk & File Systems window (with an indication that there are two paths to the device). This makes the selection of an alternate path to the LUN a bit more involved. The following steps should clarify the process of defining an alternate path for a LUN. To select an alternate hardware path: 1. From the Disk & File Systems window select the LUN you want to add. 2. From the Actions menu select "Add..." , and then select "Using The Logical Volume Manager". 20