Device Management for AIX

Terms:

Physical device physical device is the actual hard drive connected to the system

A port port is a physical connector/adapter card connected to a physical device on the system, and many ports are programmed by the system software to enable different types of devices to be added.

Device drivers are software that controls port behavior in the kernel and the data format sent to the device.

Logical device logical device is a kind of special file, it is the software interface that application and user access physical device. The data written to the logical device will be sent to the appropriate device driver, and the data read from the logical device will be read from the corresponding device driver.

The/dev directory contains logical devices that all users can access directly.

The AIX system can be configured with many devices, and the device is generally divided into two types of reads and writes:

Block device This is a structured random access device. It uses a buffer to provide a one-piece access mechanism. Block devices are usually just disk file systems.

Character device (Character device) This is a sequential data flow device that does not have a buffer.

Examples of block devices:

CD0 CD-ROM

Fd0, fd0l, fd0h disk

HD1, lv00 Logical Volume

Hdisk0 Physical Volume

Examples of character (bare) devices:

Console, LFT, Tty0 terminal

Lp0 Printer

Rmt0 Tape Drive

Tok0, ENT0 Adapter

Kmem, mem, NULL memory

Rfd0, rfd0l, rfd0h disk

RHD1, rlv00 Logical Volume

Rhdisk0 Physical Volume

Equipment classification

Class indicates what the device can do, the functional class of the device

Type represents the types of devices

Subclass indicates how the device is connected to the system

Status of the device

Available (available): Indicates that the device is available in the system and can be accessed by the user.

Defined (defined): Indicates that the system can recognize the device, but the system cannot use it, and for devices of this state, there are logical device names, address encodings, and individual attribute values.

Undefined (undefined): Represents a device supported by the system. It is not configured and does not exist in a user-defined database. The actual state does not exist, but it is conceptually considered to have this state.

You can control device status by using the Smit menu or the Mkdev, Rmdev commands.

Smit device Menu

# Smit Devices

The SMIT devices menu is used to configure devices in the system. These configuration information controls how the system operates the appropriate physical device. The contents of the device list depend on what you have installed and configured on the system.

Install/configure devices added after IPL operation Cfgmgr

The Printer/plotter notebook menu is used to configure printer devices and to set up local printers and remote printer queues.

TTY connected to a serial port device

Pty refers to pseudo terminal equipment. A pseudo terminal device provides an encapsulation of an actual existing ASCII terminal to an application, but it does not have any physical port connections.

Communication different types of communication cards

Display power management power management to turn off or darken the screen to protect the imaging tube.