Device Aliases

There are two kinds of device names:

• Full device path names (discussed in the previous section), such as /sbus@1,f8000000/esp@0,40000/sd@3,0:a

• Device aliases, such as disk

A device alias, or simply, alias, is a way of representing a device path name. An alias represents an entire device path name, not a component of it. For example, the alias disk may represent the device path name:

/sbus@1,f8000000/esp@0,40000/sd@3,0:a

Systems have predefined device aliases for most commonly-used devices, so you rarely need to type a full device path name.

The following table describes the devalias command, which is used to examine, create, and change aliases.

Table 1-3 Examining and Creating Device Aliases

Command	Description
devalias	Display all current device aliases.
devalias alias	Display the device path name corresponding to alias.
devalias alias device-path	Define an alias representing device path. If an alias with the same name already exists, the new value supersedes the old.

User-defined aliases are lost after a system reset or power cycle. If you want to create permanent aliases, you can either manually store the output of the devalias command in a portion of non-volatile RAM (NVRAM) called NVRAMRC, or use the nvalias and nvunalias commands. (See Chapter 3, Setting Configuration Parameters, for more details.)