Identifying the Faulty Disk Drive

Disk errors may be reported in a number of different ways. Often you can find messages about failing or failed disks in your system console. This information is also logged in the /usr/adm/messages file(s). These error messages typically refer to a failed disk drive by its physical device name (such as /devices/pci@6,4000/scsi@4,1/sd@3,0) and its UNIX device instance name (such as sd14). In some cases, a faulty disk may be identified by its logical device name, such as c2t3d0. In addition, some applications may report a disk slot number (0 through 19) or activate an LED located next to the disk drive itself (see Figure 3-2).

Figure 3-2 Disk Slot Numbers and LED Locations

In order to perform a disk hot-plug procedure, you need to know the slot number of the faulty disk (0 through 19) and its logical device name (for example, c2t3d0). If you know the disk slot number, it is possible to determine the logical device name, and vice versa. It is also possible to determine both the disk slot number and the logical device name from a physical device name (such as /devices/pci@6,4000/scsi@4,1/sd@3,0).

To make the necessary translation from one form of disk identifier to another, see Chapter 4, Mapping Between Logical and Physical Device Names ." Once you have determined both the disk slot number and logical device name, you are ready to continue with this procedure.