Similarly, you might need to start a manual inventory if the host application software indicates  that a problem exists with the library inventory. The TS4500 tape library provides two inventory options, as shown in Figure 4-152. Select the type of scan that is required: Use this option when a faster inventory is preferred. This option scans other tiers only if a  discrepancy is identified. Use this option when a full library inventory is required. This option is not concurrent, and  it can last many hours, depending on the number of cartridges in the library. Note:  The depth of a cartridge location in a HD slot is known as a  tier . Frame drive side  slots are for the cartridges that are immediately accessible in an HD slot (these are Tier 1  cartridges). Behind that is Tier 2, and so on. The maximum tier in an LTO HD slot is Tier 5.  The maximum tier in a 3592 HD slot is Tier 4. The single slots on the door-side of a frame  are referred to as Tier 0 slots. When no frame is selected, select  Inventory  from the Actions menu to start an inventory of  the library. When a frame is selected, the Inventory option inventories only that frame.  Right-click any frame and select  Actions  Inventory  to inventory only that frame. You can inventory a single frame by selecting it and then clicking  Actions  Inventory . If you  do not select a frame, all frames are inventoried. In a high-density (HD) library, a standard inventory is a scan of tier 0 and tier 1. However, at  certain times, it is necessary to inventory all tiers. This operation takes more time because it  requires moving the cartridges within an HD slot to scan each bar code. For all inventory  operations, tier 2 and higher in an HD slot are only scanned when one of the following  changes occurs: Chapter 4. TS4500 management graphical user interface  303 Inventory all tiers GLYPH<SM590000> Scan tier 0 and tier 1 GLYPH<SM590000> Scan all tiers GLYPH<SM590000> A tier 1 cartridge bar code label changed, which is detected during inventory. Only the  slots for which the tier 1 label changed are audited. GLYPH<SM590000> Enough tier 1 bar code labels changed in a column to warrant an audit of the entire  column of HD slots. GLYPH<SM590000> An “Inventory all tiers” is requested through the TS4500 management GUI. Figure 4-152 Inventory Frame