man dmidecode Command

Man page for apt-get dmidecode Command

Man Page for dmidecode in Linux

Ubuntu Man Command : man dmidecode

Man Dmidecode  Command

This tutorial shows the man page for man dmidecode in linux.

Open terminal with 'su' access and type the command as shown below:
man dmidecode

Result of the Command Execution shown below:

DMIDECODE(8)                                                                                                                                            DMIDECODE(8)

dmidecode DMI table decoder

dmidecode [OPTIONS]

dmidecode is a tool for dumping a computer's DMI (some say SMBIOS) table contents in a human readable format. This table contains a description of the sys
tem's hardware components, as well as other useful pieces of information such as serial numbers and BIOS revision. Thanks to this table, you can retrieve
this information without having to probe for the actual hardware. While this is a good point in terms of report speed and safeness, this also makes the pre
sented information possibly unreliable.

The DMI table doesn't only describe what the system is currently made of, it also can report the possible evolutions (such as the fastest supported CPU or
the maximal amount of memory supported).

SMBIOS stands for System Management BIOS, while DMI stands for Desktop Management Interface. Both standards are tightly related and developed by the DMTF
(Desktop Management Task Force).

As you run it, dmidecode will try to locate the DMI table. If it succeeds, it will then parse this table and display a list of records like this one:

Handle 0x0002, DMI type 2, 8 bytes. Base Board Information
Manufacturer: Intel
Product Name: C440GX+
Version: 727281 001
Serial Number: INCY92700942

Each record has:

o A handle. This is a unique identifier, which allows records to reference each other. For example, processor records usually reference cache memory records
using their handles.

o A type. The SMBIOS specification defines different types of elements a computer can be made of. In this example, the type is 2, which means that the record
contains "Base Board Information".

o A size. Each record has a 4 byte header (2 for the handle, 1 for the type, 1 for the size), the rest is used by the record data. This value doesn't take
text strings into account (these are placed at the end of the record), so the actual length of the record may be (and is often) greater than the displayed

o Decoded values. The information presented of course depends on the type of record. Here, we learn about the board's manufacturer, model, version and serial

d, dev mem FILE
Read memory from device FILE (default: /dev/mem)

q, quiet
Be less verbose. Unknown, inactive and OEM specific entries are not displayed. Meta data and handle references are hidden. Mutually exclusive with

s, string KEYWORD
Only display the value of the DMI string identified by KEYWORD. KEYWORD must be a keyword from the following list: bios vendor, bios version, bios
release date, system manufacturer, system product name, system version, system serial number, system uuid, baseboard manufacturer, baseboard product
name, baseboard version, baseboard serial number, baseboard asset tag, chassis manufacturer, chassis type, chassis version, chassis serial number,
chassis asset tag, processor family, processor manufacturer, processor version, processor frequency. Each keyword corresponds to a given DMI type and
a given offset within this entry type. Not all strings may be meaningful or even defined on all systems. Some keywords may return more than one
result on some systems (e.g. processor version on a multi processor system). If KEYWORD is not provided or not valid, a list of all valid keywords
is printed and dmidecode exits with an error. This option cannot be used more than once, and implies quiet. Mutually exclusive with type and

t, type TYPE
Only display the entries of type TYPE. TYPE can be either a DMI type number, or a comma separated list of type numbers, or a keyword from the follow
ing list: bios, system, baseboard, chassis, processor, memory, cache, connector, slot. Refer to the DMI TYPES section below for details. If this
option is used more than once, the set of displayed entries will be the union of all the given types. If TYPE is not provided or not valid, a list of
all valid keywords is printed and dmidecode exits with an error. Mutually exclusive with string.

u, dump
Do not decode the entries, dump their contents as hexadecimal instead. Note that this is still a text output, no binary data will be thrown upon you.
The strings attached to each entry are displayed as both hexadecimal and ASCII. This option is mainly useful for debugging. Mutually exclusive with
quiet and string.

h, help
Display usage information and exit

V, version
Display the version and exit

The SMBIOS specification defines the following DMI types:

Type Information

1 System
2 Base Board
3 Chassis
4 Processor
5 Memory Controller
6 Memory Module
7 Cache
8 Port Connector
9 System Slots
10 On Board Devices
11 OEM Strings
12 System Configuration Options
13 BIOS Language
14 Group Associations
15 System Event Log
16 Physical Memory Array
17 Memory Device
18 32 bit Memory Error
19 Memory Array Mapped Address
20 Memory Device Mapped Address
21 Built in Pointing Device
22 Portable Battery
23 System Reset
24 Hardware Security
25 System Power Controls
26 Voltage Probe
27 Cooling Device
28 Temperature Probe
29 Electrical Current Probe
30 Out of band Remote Access
31 Boot Integrity Services
32 System Boot
33 64 bit Memory Error
34 Management Device
35 Management Device Component
36 Management Device Threshold Data
37 Memory Channel
38 IPMI Device
39 Power Supply

Additionally, type 126 is used for disabled entries and type 127 is an end of table marker. Types 128 to 255 are for OEM specific data. dmidecode will dis
play these entries by default, but it can only decode them when the vendors have contributed documentation or code for them.

Keywords can be used instead of type numbers with type. Each keyword is equivalent to a list of type numbers:

Keyword Types

bios 0, 13
system 1, 12, 15, 23, 32
baseboard 2, 10
chassis 3
processor 4
memory 5, 6, 16, 17
cache 7
connector 8
slot 9

Keywords are matched case insensitively. The following command lines are equivalent:

o dmidecode type 0 type 13

o dmidecode type 0,13

o dmidecode type bios

o dmidecode type BIOS


More often than not, information contained in the DMI tables is inaccurate, incomplete or simply wrong.

Alan Cox, Jean Delvare

biosdecode(8), mem(4), ownership(8), vpddecode(8)

dmidecode February 2007 DMIDECODE(8)

Related Topics

Apt Get Commands