Using Dmidecode | System Information

Introduction

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 system's hardware components as well as other useful pieces of information such as serial numbers and BIOS revision. This tutorial will guide you through using dmidecode from start to finish with detailed explanations and examples.

Installation

Before you can use dmidecode, you need to have it installed on your system. Most Linux distributions include dmidecode by default, but if it is not installed, you can install it using your package manager.

For Debian-based distributions (e.g., Ubuntu):

sudo apt-get install dmidecode

For Red Hat-based distributions (e.g., CentOS):

sudo yum install dmidecode

Basic Usage

The basic command to use dmidecode is simply:

sudo dmidecode

This will output a lot of information about your system's hardware. Here is an example of the kind of information you might see:

# dmidecode 3.2
Getting SMBIOS data from sysfs.
SMBIOS 2.8 present.

Handle 0x0001, DMI type 1, 27 bytes
System Information
    Manufacturer: Example Corp.
    Product Name: Example Product
    Version: 1.0
    Serial Number: ABCD1234
    UUID: 12345678-1234-5678-1234-567812345678
    Wake-up Type: Power Switch
    SKU Number: Not Specified
    Family: Example Family

Filtering Output

To make the output more manageable, you can filter it to show only certain types of information. Use the -t option followed by the type of information you are interested in. For example, to display only the system information:

sudo dmidecode -t system

# dmidecode 3.2
Getting SMBIOS data from sysfs.
SMBIOS 2.8 present.

Handle 0x0001, DMI type 1, 27 bytes
System Information
    Manufacturer: Example Corp.
    Product Name: Example Product
    Version: 1.0
    Serial Number: ABCD1234
    UUID: 12345678-1234-5678-1234-567812345678
    Wake-up Type: Power Switch
    SKU Number: Not Specified
    Family: Example Family

Other common types are:

bios - Show BIOS information
baseboard - Show baseboard information
processor - Show processor information
memory - Show memory information

Specific Types

Here are examples of how to use dmidecode to extract specific types of information:

BIOS Information:

sudo dmidecode -t bios

# dmidecode 3.2
Getting SMBIOS data from sysfs.
SMBIOS 2.8 present.

Handle 0x0000, DMI type 0, 24 bytes
BIOS Information
    Vendor: Example BIOS Vendor
    Version: 1.0
    Release Date: 01/01/2020
    Address: 0xF0000
    Runtime Size: 64 kB
    ROM Size: 8192 kB

Processor Information:

sudo dmidecode -t processor

# dmidecode 3.2
Getting SMBIOS data from sysfs.
SMBIOS 2.8 present.

Handle 0x0004, DMI type 4, 48 bytes
Processor Information
    Socket Designation: CPU 1
    Type: Central Processor
    Family: Example Family
    Manufacturer: Example Manufacturer
    ID: 12345678
    Version: Example Version
    Voltage: 1.2 V
    External Clock: 100 MHz
    Max Speed: 3500 MHz
    Current Speed: 3400 MHz

Conclusion

The dmidecode command is a powerful tool for extracting detailed information about your system's hardware. By using various options and filters, you can tailor the output to meet your needs. Whether you are troubleshooting hardware issues or simply want to know more about the components in your system, dmidecode provides a wealth of information at your fingertips.