If you set up a LUN that is larger than 2 terabytes (TB), be aware that older clients (those running Xsan on Mac OS X 10.3 Panther or Xsan 1.2 or earlier on Mac OS X 10.4 Tiger) cannot read these large LUNs. A dialog appears on these older clients that says the LUN is unreadable. Be sure to click Ignore to dismiss this dialog. Do not click Format, or information on the corresponding Xsan volume will be lost. If you use LUNs greater than 2 TB, you should upgrade all SAN clients to Xsan 1.3 or later on Mac OS X or Mac OS X Server v10.4.