logical unit number (LUN)

A number assigned to peripheral units during autoload or system generation time. Such numbers can be altered whenever convenient, in contrast to a physical unitnumber. Forexample, a tape unit may be assigned logical unit number 5 and a read operation from unit 5 will result in reading a tape.; 在自動裝入或系統生成時,一種分配給外部設備的編號。這樣的編號在任何方便的時候都 可以變換,只要與物理設備號相對應就可以。例如,一磁帶機可以分配為邏輯設備號5,那么, 從設備5的讀操作將導致讀帶。