dmidecode

Get information about hardware under Linux system

Supplementary instructions

dmidecode command allows you to obtain information about hardware under Linux system. The function of dmidecode is to decode the information in the DMI database and display it in readable text. Since DMI information can be modified manually, the information inside may not be accurate information of the system. dmidecode follows the SMBIOS/DMI standard, and the information it outputs includes BIOS, system, motherboard, processor, memory, cache, etc.

DMI (Desktop Management Interface, DMI) is a management system that helps collect computer system information. The collection of DMI information must be carried out in strict compliance with SMBIOS specifications. SMBIOS (System Management BIOS) is a unified specification that motherboard or system manufacturers need to follow to display product management information in a standard format. SMBIOS and DMI are open technical standards drafted by the industry guidance organization Desktop Management Task Force (DMTF). The DMI design is suitable for any platform and operating system.

DMI acts as the interface between management tools and system layers. It establishes a standard manageable system to make it easier for computer manufacturers and users to understand the system. The main component of DMI is the Management Information Format (MIF) database. This database contains all information about computer systems and accessories. Through DMI, users can obtain serial numbers, computer manufacturers, serial port information and other system accessories information.

grammar

dmidecode [options]

Options

-d: (default:/dev/mem) Read information from the device file, and the output content is the same as the standard output without parameters.
-h: Display help information.
-s: Only display the information of the specified DMI string. (string)
-t: Only display information about the specified entry. (type)
-u: Display the undecoded raw entry contents.
--dump-bin file: Dump DMI data into a binary file.
--from-dump FILE: Read DMI data from a binary file.
-V: Display version information.

dmidecode parameter string and type list:

(1) Valid string keywords are:

(2) Valid type keywords are:

*bios

(3) All encoding list of type:

*BIOS *System *Base Board

Chassis
Processor
Memory Controller
Memory Module
Cache
Port Connector
System Slots *On Board Devices *OEM Strings
System Configuration Options
BIOS Language *Group Associations
System Event Log
Physical Memory Array
Memory Device
32-bit Memory Error
Memory Array Mapped Address
Memory Device Mapped Address
Built-in Pointing Device *Portable Battery
System Reset
Hardware Security
System Power Controls
Voltage Probe
Cooling Device
Temperature Probe
Electrical Current Probe
Out-of-band Remote Access
Boot Integrity Services
System Boot
64-bit Memory Error *Management Device *Management Device Component *Management Device Threshold Data
Memory Channel
IPMI Device
Power Supply *Additional Information *Onboard Device

Example

dmidecode -t 1 # View server information
dmidecode | grep 'Product Name' # View server model
dmidecode |grep 'Serial Number' # Check the serial number of the motherboard
dmidecode -t 2 # View motherboard information
dmidecode -s system-serial-number # View the system serial number
dmidecode -t memory # View memory information
dmidecode -t 11 # View OEM information
dmidecode -t 17 # Check the number of memory sticks
dmidecode -t 16 # Query memory information
dmidecode -t 4 # View CPU information

cat /proc/scsi/scsi # View server hard disk information

Executing the dmidecode command without options will usually output all hardware information. The dmidecode command has a very useful option -t, which can output relevant information according to the specified type. If you want to obtain processor information, you can execute:

[root@localhost ~]# dmidecode -t processor
#dmidecode 2.11
SMBIOS 2.5 present.

Handle 0x0001, DMI type 4, 40 bytes
Processor Information
         Socket Designation: Node 1 Socket 1
         Type: Central Processor
         Family: Xeon MP
         Manufacturer: Intel(R) Corporation
         id: C2 06 02 00 FF FB EB BF
         Signature: Type 0, Family 6, Model 44, Stepping 2
         Flags:
                 FPU (Floating-point unit on-chip)
                 VME (Virtual mode extension)
                 DE (Debugging extension)
                 PSE (Page size extension)
                 TSC (time stamp counter)
                 MSR (Model specific registers)
                 PAE (Physical address extension)
                 MCE (Machine check exception)
                 CX8 (CMPXCHG8 instruction supported)
                 APIC (On-chip APIC hardware supported)
                 SEP (Fast system call)
                 MTRR (Memory type range registers)
                 PGE (Page global enable)
                 MCA (Machine check architecture)
                 CMOV (Conditional move instruction supported)
                 PAT (Page attribute table)
                 PSE-36 (36-bit page size extension)
                 CLFSH (CLFLUSH instruction supported)
                 DS (Debug store)
                 ACPI (ACPI supported)
                 MMX (MMX technology supported)
                 FXSR (FXSAVE and FXSTOR instructions supported)
                 SSE (Streaming SIMD extensions)
                 SSE2 (Streaming SIMD extensions 2)
                 ss (Self-snoop)
                 HTT (Multi-threading)
                 TM (Thermal monitor supported)
                 PBE (Pending break enabled)
         Version: Intel(R) Xeon(R) CPU E5620 @ 2.40GHz
         Voltage: 1.2 V
         External clock: 5866 MHz
         Max Speed: 4400 MHz
         Current Speed: 2400 MHz
         Status: Populated, Enabled
         Upgrade: ZIF Socket
         L1 Cache Handle: 0x0002
         L2 Cache Handle: 0x0003
         L3 Cache Handle: 0x0004
         Serial Number: Not Specified
         Asset Tag: Not Specified
         Part Number: Not Specified
         Core Count: 4
         Core Enabled: 4
         Thread Count: 8
         Characteristics:
                 64-bit capable

Handle 0x0055, DMI type 4, 40 bytes
Processor Information
         Socket Designation: Node 1 Socket 2
         Type: Central Processor
         Family: Xeon MP
         Manufacturer: Not Specified
         ID: 00 00 00 00 00 00 00 00
         Signature: Type 0, Family 0, Model 0, Stepping 0
         Flags: None
         Version: Not Specified
         Voltage: 1.2 V
         External clock: 5866 MHz
         Max Speed: 4400 MHz
         Current Speed: Unknown
         Status: Unpopulated
         Upgrade: ZIF Socket
         L1 Cache Handle: Not Provided
         L2 Cache Handle: Not Provided
         L3 Cache Handle: Not Provided
         Serial Number: Not Specified
         Asset Tag: Not Specified
         Part Number: Not Specified
         Characteristics: None

Check the number of memory slots and how many slots are used. How big is each memory and how much used memory is

dmidecode|grep -P -A5 "Memory\s+Device"|grep Size|grep -v Range

# Size: 2048 MB
# Size: 2048 MB
# Size: 4096 MB
# Size: No Module Installed

Check the maximum memory capacity supported by the memory

dmidecode|grep -P 'Maximum\s+Capacity'

# Maximum Capacity: 16 GB

Check memory frequency

dmidecode|grep -A16 "Memory Device"

# Memory Device
# Array Handle: 0x1000
# Error Information Handle: Not Provided
# Total Width: 72 bits
# Data Width: 64 bits
# Size: 2048 MB
# Form Factor: DIMM
# Set: 1
# Locator: DIMM_A1
# Bank Locator: Not Specified
# Type: DDR3
# Type Detail: Synchronous Unbuffered (Unregistered)
# Speed: 1333 MHz
# Manufacturer: 00CE000080CE
# Serial Number: 4830F3E1
# Asset Tag: 01093200
# Part Number: M391B5673EH1-CH9
# --
# Memory Device
# Array Handle: 0x1000
# Error Information Handle: Not Provided
# Total Width: 72 bits
# Data Width: 64 bits
# Size: 2048 MB
# Form Factor: DIMM
# Set: 1
# Locator: DIMM_A2
# Bank Locator: Not Specified
# Type: DDR3
# Type Detail: Synchronous Unbuffered (Unregistered)
# Speed: 1333 MHz
# Manufacturer: 00AD000080AD
# Serial Number: 1BA1F0B5
# Asset Tag: 01110900
# Part Number: HMT325U7BFR8C-H9
# --

dmidecode|grep -A16 "Memory Device"|grep 'Speed'

# Speed: 1333 MHz
# Speed: 1333 MHz
# Speed: 1333 MHz
#Speed: Unknown

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