Xsan

Promise RAID: Enable LUN Masking

Using the Promise RAID it is possible to split up an Array into multiple LUNs, which would then be presented to the OS and able to be formatted at will.  These do not have to correspond to a Physical segmentation as was the case with the Apple Xserve RAID but instead can be as small or as large as the actual disk array allows.  Once split up you can run the LUNs through a fibre channel switch and mount them at will on various servers (although unless the file system supports clustering on only one at a time).  If you are using HFS+ for the file system you will then want to enable LUN masking to keep multiple servers from trying to mount up the same volume.  To enable LUN masking on the Promise RAID, from the web GUI click on Storage Services and then click on the LUN Map tab.  Here, check the box for Enable LUN Masking.  From this point forward you will need to enable a mask in able to be able to see a LUN from a given controller.