NAME
dmidecode - \s-1DMI\s0 table decoder
SYNOPSIS
dmidecode
[OPTIONS]
DESCRIPTION
dmidecode
is a tool for dumping a computer's \s-1DMI\s0 (some say \s-1SMBIOS\s0) table
contents in a human-readable format. This table contains a description of the
system's hardware components, as well as other useful pieces of information
such as serial numbers and \s-1BIOS\s0 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 presented information possibly unreliable.
The \s-1DMI\s0 table doesn't only describe what the system is currently made
of, it also can report the possible evolutions (such as the fastest supported
\s-1CPU\s0 or the maximal amount of memory supported).
\s-1SMBIOS\s0 stands for System Management \s-1BIOS\s0, while \s-1DMI\s0
stands for Desktop Management Interface. Both standards are tightly related
and developed by the \s-1DMTF\s0 (Desktop Management Task Force).
As you run it,
dmidecode
will try to locate the \s-1DMI\s0 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:
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.
A type. The \s-1SMBIOS\s0 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".
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 value.
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 number.
OPTIONS
R -d , --dev-mem FILE
Read memory from device FILE (default: /dev/mem)
R -q , --quiet
Be less verbose. Unknown, inactive and \s-1OEM\s0-specific entries are not
displayed. Meta-data and handle references are hidden. Mutually exclusive
with --dump.
R -s , --string KEYWORD
Only display the value of the \s-1DMI\s0 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 \s-1DMI\s0 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 --dump.
R -t , --type TYPE
Only display the entries of type TYPE. TYPE can be either a
\s-1DMI\s0 type number, or a comma-separated list of type numbers, or a
keyword from the following 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.
R -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 \s-1ASCII\s0. This option is mainly useful for debugging.
Mutually exclusive with --quiet and --string.
R -h , --help
Display usage information and exit
R -V , --version
Display the version and exit
DMI TYPES
The \s-1SMBIOS\s0 specification defines the following \s-1DMI\s0 types:
r l
__
r l.
Type Information
0 BIOS
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 \s-1OEM\s0-specific data.
dmidecode
will display 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:
l l
__
l l.
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:
dmidecode --type 0 --type 13
dmidecode --type 0,13
dmidecode --type bios
dmidecode --type BIOS
FILES
/dev/mem
BUGS
More often than not, information contained in the \s-1DMI\s0 tables is inaccurate,
incomplete or simply wrong.
AUTHORS
Alan Cox, Jean Delvare
SEE ALSO
ČLÁNKY DO MAILU