The Linux operating system provides numerous command-line utilities to inspect hardware details on your system. These tools allow users to access specific information about the CPU, memory, PCI devices, and more. Some commands, like lshw, offer a complete hardware overview, while others focus on specific components, such as lscpu for processors or lsusb for USB devices. These commands are critical when diagnosing hardware issues or checking compatibility.
Most Linux distributions include these utilities by default, which makes them accessible for both basic and advanced users. Tools like dmidecode are particularly useful for viewing system firmware and BIOS data, while lsmem displays memory-related information. For listing detailed information about connected devices, lspci and lsusb are commonly used. Each tool can also filter and format its output for better clarity, making it adaptable to specific use cases.
Additionally, the Linux filesystem contains directories like /proc and /sys where detailed hardware information is available. These directories store real-time and persistent data about the system. The combination of command-line tools and system directories enables deep insight into your system's hardware, whether you're performing routine checks or troubleshooting more complex issues.
Steps to check hardware information in Linux:
- Open the terminal.
- Use lshw to display all installed hardware.
$ sudo lshw [sudo] password for user: host description: Computer product: VMware Virtual Platform vendor: VMware, Inc. version: None serial: VMware-56 4d 6d 49 cc cb 86 de-d4 ca fa ad 4b cf 54 30 width: 64 bits capabilities: smbios-2.7 dmi-2.7 smp vsyscall32 configuration: administrator_password=enabled boot=normal frontpanel_password=unknown keyboard_password=unknown power-on_password=disabled uuid=564D6D49-CCCB-86DE-D4CA-FAAD4BCF5430 *-core description: Motherboard product: 440BX Desktop Reference Platform vendor: Intel Corporation physical id: 0 version: None serial: None *-firmware description: BIOS vendor: Phoenix Technologies LTD physical id: 0 version: 6.00 date: 07/22/2020 size: 86KiB capabilities: isa pci pcmcia pnp apm upgrade shadowing escd cdboot bootselect edd int5printscreen int9keyboard int14serial int17printer int10video acpi smartbattery biosbootspecification netboot *-cpu:0 description: CPU product: Intel(R) Core(TM) i9-9880H CPU @ 2.30GHz vendor: Intel Corp. physical id: 1 bus info: cpu@0 version: Intel(R) Core(TM) i9-9880H CPU @ 2.30GHz slot: CPU #000 size: 2300MHz capacity: 4230MHz width: 64 bits capabilities: lm fpu fpu_exception wp vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ss syscall nx pdpe1gb rdtscp x86-64 constant_tsc arch_perfmon nopl xtopology tsc_reliable nonstop_tsc cpuid pni pclmulqdq ssse3 fma cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand hypervisor lahf_lm abm 3dnowprefetch cpuid_fault invpcid_single ssbd ibrs ibpb stibp ibrs_enhanced fsgsbase tsc_adjust bmi1 avx2 smep bmi2 invpcid rdseed adx smap clflushopt xsaveopt xsavec xgetbv1 xsaves arat md_clear flush_l1d arch_capabilities configuration: cores=1 enabledcores=1 *-cache:0 description: L1 cache physical id: 0 slot: L1 size: 16KiB capacity: 16KiB capabilities: asynchronous internal write-back configuration: level=1 *-cache:1 description: L1 cache physical id: 1 slot: L1 size: 16KiB capacity: 16KiB capabilities: asynchronous internal write-back configuration: level=1 ##### snippedUse lshw for a comprehensive overview of all hardware components, including CPU, memory, and storage devices.
More options for lshw:
$ lshw --help Hardware Lister (lshw) - usage: lshw [-format] [-options ...] lshw -version -version print program version () format can be -html output hardware tree as HTML -xml output hardware tree as XML -json output hardware tree as a JSON object -short output hardware paths -businfo output bus information options can be -class CLASS only show a certain class of hardware -C CLASS same as '-class CLASS' -c CLASS same as '-class CLASS' -disable TEST disable a test (like pci, isapnp, cpuid, etc. ) -enable TEST enable a test (like pci, isapnp, cpuid, etc. ) -quiet don't display status -sanitize sanitize output (remove sensitive information like serial numbers, etc.) -numeric output numeric IDs (for PCI, USB, etc.) -notime exclude volatile attributes (timestamps) from output - Run lspci to list connected PCI devices.
$ lspci 00:00.0 Host bridge: Intel Corporation 440BX/ZX/DX - 82443BX/ZX/DX Host bridge (rev 01) 00:01.0 PCI bridge: Intel Corporation 440BX/ZX/DX - 82443BX/ZX/DX AGP bridge (rev 01) 00:07.0 ISA bridge: Intel Corporation 82371AB/EB/MB PIIX4 ISA (rev 08) 00:07.1 IDE interface: Intel Corporation 82371AB/EB/MB PIIX4 IDE (rev 01) 00:07.3 Bridge: Intel Corporation 82371AB/EB/MB PIIX4 ACPI (rev 08) 00:07.7 System peripheral: VMware Virtual Machine Communication Interface (rev 10) 00:0f.0 VGA compatible controller: VMware SVGA II Adapter 00:10.0 SCSI storage controller: Broadcom / LSI 53c1030 PCI-X Fusion-MPT Dual Ultra320 SCSI (rev 01) 00:11.0 PCI bridge: VMware PCI bridge (rev 02) 00:15.0 PCI bridge: VMware PCI Express Root Port (rev 01) 00:15.1 PCI bridge: VMware PCI Express Root Port (rev 01) 00:15.2 PCI bridge: VMware PCI Express Root Port (rev 01) 00:15.3 PCI bridge: VMware PCI Express Root Port (rev 01) 00:15.4 PCI bridge: VMware PCI Express Root Port (rev 01) 00:15.5 PCI bridge: VMware PCI Express Root Port (rev 01) 00:15.6 PCI bridge: VMware PCI Express Root Port (rev 01) 00:15.7 PCI bridge: VMware PCI Express Root Port (rev 01) 00:16.0 PCI bridge: VMware PCI Express Root Port (rev 01) 00:16.1 PCI bridge: VMware PCI Express Root Port (rev 01) 00:16.2 PCI bridge: VMware PCI Express Root Port (rev 01) 00:16.3 PCI bridge: VMware PCI Express Root Port (rev 01) 00:16.4 PCI bridge: VMware PCI Express Root Port (rev 01) 00:16.5 PCI bridge: VMware PCI Express Root Port (rev 01) 00:16.6 PCI bridge: VMware PCI Express Root Port (rev 01) 00:16.7 PCI bridge: VMware PCI Express Root Port (rev 01) 00:17.0 PCI bridge: VMware PCI Express Root Port (rev 01) 00:17.1 PCI bridge: VMware PCI Express Root Port (rev 01) 00:17.2 PCI bridge: VMware PCI Express Root Port (rev 01) 00:17.3 PCI bridge: VMware PCI Express Root Port (rev 01) 00:17.4 PCI bridge: VMware PCI Express Root Port (rev 01) 00:17.5 PCI bridge: VMware PCI Express Root Port (rev 01) 00:17.6 PCI bridge: VMware PCI Express Root Port (rev 01) 00:17.7 PCI bridge: VMware PCI Express Root Port (rev 01) 00:18.0 PCI bridge: VMware PCI Express Root Port (rev 01) 00:18.1 PCI bridge: VMware PCI Express Root Port (rev 01) 00:18.2 PCI bridge: VMware PCI Express Root Port (rev 01) 00:18.3 PCI bridge: VMware PCI Express Root Port (rev 01) 00:18.4 PCI bridge: VMware PCI Express Root Port (rev 01) 00:18.5 PCI bridge: VMware PCI Express Root Port (rev 01) 00:18.6 PCI bridge: VMware PCI Express Root Port (rev 01) 00:18.7 PCI bridge: VMware PCI Express Root Port (rev 01) 02:00.0 USB controller: VMware USB1.1 UHCI Controller 02:01.0 Ethernet controller: Intel Corporation 82545EM Gigabit Ethernet Controller (Copper) (rev 01) 02:03.0 USB controller: VMware USB2 EHCI Controller 02:05.0 SATA controller: VMware SATA AHCI controller
Use lspci to view PCI devices such as network cards, sound cards, and GPUs.
More options for lspci:
$ lspci help Usage: lspci [<switches>] Basic display modes: -mm Produce machine-readable output (single -m for an obsolete format) -t Show bus tree Display options: -v Be verbose (-vv or -vvv for higher verbosity) -k Show kernel drivers handling each device -x Show hex-dump of the standard part of the config space -xxx Show hex-dump of the whole config space (dangerous; root only) -xxxx Show hex-dump of the 4096-byte extended config space (root only) -b Bus-centric view (addresses and IRQ's as seen by the bus) -D Always show domain numbers -P Display bridge path in addition to bus and device number -PP Display bus path in addition to bus and device number Resolving of device ID's to names: -n Show numeric ID's -nn Show both textual and numeric ID's (names & numbers) -q Query the PCI ID database for unknown ID's via DNS -qq As above, but re-query locally cached entries -Q Query the PCI ID database for all ID's via DNS Selection of devices: -s [[[[<domain>]:]<bus>]:][<slot>][.[<func>]] Show only devices in selected slots -d [<vendor>]:[<device>][:<class>] Show only devices with specified ID's Other options: -i <file> Use specified ID database instead of /usr/share/misc/pci.ids.gz -p <file> Look up kernel modules in a given file instead of default modules.pcimap -M Enable `bus mapping' mode (dangerous; root only) PCI access options: -A <method> Use the specified PCI access method (see `-A help' for a list) -O <par>=<val> Set PCI access parameter (see `-O help' for a list) -G Enable PCI access debugging -H <mode> Use direct hardware access (<mode> = 1 or 2) -F <file> Read PCI configuration dump from a given file
- Use lsusb to list connected USB devices.
$ lsusb Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 002 Device 004: ID 0e0f:0008 VMware, Inc. VMware Virtual USB Mouse Bus 002 Device 003: ID 0e0f:0002 VMware, Inc. Virtual USB Hub Bus 002 Device 002: ID 0e0f:0003 VMware, Inc. Virtual Mouse Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
More options for lsusb:
$ lsusb --help Usage: lsusb [options]... List USB devices -v, --verbose Increase verbosity (show descriptors) -s [[bus]:][devnum] Show only devices with specified device and/or bus numbers (in decimal) -d vendor:[product] Show only devices with the specified vendor and product ID numbers (in hexadecimal) -D device Selects which device lsusb will examine -t, --tree Dump the physical USB device hierarchy as a tree -V, --version Show version of program -h, --help Show usage and help - Use lscpu to view CPU architecture details.
$ lscpu Architecture: x86_64 CPU op-mode(s): 32-bit, 64-bit Byte Order: Little Endian Address sizes: 45 bits physical, 48 bits virtual CPU(s): 2 On-line CPU(s) list: 0,1 Thread(s) per core: 1 Core(s) per socket: 1 Socket(s): 2 NUMA node(s): 1 Vendor ID: GenuineIntel CPU family: 6 Model: 158 Model name: Intel(R) Core(TM) i9-9880H CPU @ 2.30GHz Stepping: 13 CPU MHz: 2304.000 BogoMIPS: 4608.00 Hypervisor vendor: VMware Virtualization type: full L1d cache: 64 KiB L1i cache: 64 KiB L2 cache: 512 KiB L3 cache: 32 MiB NUMA node0 CPU(s): 0,1 Vulnerability Itlb multihit: KVM: Mitigation: VMX unsupported Vulnerability L1tf: Not affected Vulnerability Mds: Not affected Vulnerability Meltdown: Not affected Vulnerability Spec store bypass: Mitigation; Speculative Store Bypass disabled via prctl and seccomp Vulnerability Spectre v1: Mitigation; usercopy/swapgs barriers and __use r pointer sanitization Vulnerability Spectre v2: Mitigation; Enhanced IBRS, IBPB conditional, R SB filling Vulnerability Srbds: Mitigation; TSX disabled Vulnerability Tsx async abort: Not affected Flags: fpu vme de pse tsc msr pae mce cx8 apic sep mt rr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ss syscall nx pdpe1gb rdtscp lm constant _tsc arch_perfmon nopl xtopology tsc_reliable nonstop_tsc cpuid pni pclmulqdq ssse3 fma cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_de adline_timer aes xsave avx f16c rdrand hypervi sor lahf_lm abm 3dnowprefetch cpuid_fault invp cid_single ssbd ibrs ibpb stibp ibrs_enhanced fsgsbase tsc_adjust bmi1 avx2 smep bmi2 invpci d rdseed adx smap clflushopt xsaveopt xsavec x getbv1 xsaves arat md_clear flush_l1d arch_cap abilitiesThe lscpu command shows detailed CPU information such as architecture, core count, and supported features.
More options for lscpu:
$ lscpu --help Usage: lscpu [options] Display information about the CPU architecture. Options: -a, --all print both online and offline CPUs (default for -e) -b, --online print online CPUs only (default for -p) -B, --bytes print sizes in bytes rather than in human readable format -C, --caches[=<list>] info about caches in extended readable format -c, --offline print offline CPUs only -J, --json use JSON for default or extended format -e, --extended[=<list>] print out an extended readable format -p, --parse[=<list>] print out a parsable format -s, --sysroot <dir> use specified directory as system root -x, --hex print hexadecimal masks rather than lists of CPUs -y, --physical print physical instead of logical IDs --output-all print all available columns for -e, -p or -C -h, --help display this help -V, --version display version Available output columns for -e or -p: CPU logical CPU number CORE logical core number SOCKET logical socket number NODE logical NUMA node number BOOK logical book number DRAWER logical drawer number CACHE shows how caches are shared between CPUs POLARIZATION CPU dispatching mode on virtual hardware ADDRESS physical address of a CPU CONFIGURED shows if the hypervisor has allocated the CPU ONLINE shows if Linux currently makes use of the CPU MAXMHZ shows the maximum MHz of the CPU MINMHZ shows the minimum MHz of the CPU Available output columns for -C: ALL-SIZE size of all system caches LEVEL cache level NAME cache name ONE-SIZE size of one cache TYPE cache type WAYS ways of associativity For more details see lscpu(1). - Use lsmem to check memory status and details.
$ lsmem RANGE SIZE STATE REMOVABLE BLOCK 0x0000000000000000-0x00000000bfffffff 3G online yes 0-23 0x0000000100000000-0x000000013fffffff 1G online yes 32-39 Memory block size: 128M Total online memory: 4G Total offline memory: 0B
The lsmem command provides a view of available memory blocks and their status.
More options for lsmem:
$ lsmem --help Usage: lsmem [options] List the ranges of available memory with their online status. Options: -J, --json use JSON output format -P, --pairs use key="value" output format -a, --all list each individual memory block -b, --bytes print SIZE in bytes rather than in human readable format -n, --noheadings don't print headings -o, --output <list> output columns --output-all output all columns -r, --raw use raw output format -S, --split <list> split ranges by specified columns -s, --sysroot <dir> use the specified directory as system root --summary[=when] print summary information (never,always or only) -h, --help display this help -V, --version display version Available output columns: RANGE start and end address of the memory range SIZE size of the memory range STATE online status of the memory range REMOVABLE memory is removable BLOCK memory block number or blocks range NODE numa node of memory ZONES valid zones for the memory range For more details see lsmem(1). - Run lsblk to list available block storage devices.
$ lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT loop0 7:0 0 135.8M 1 loop /snap/chromium/1461 loop1 7:1 0 135.7M 1 loop /snap/chromium/1466 loop2 7:2 0 55.4M 1 loop /snap/core18/1932 loop3 7:3 0 162.9M 1 loop /snap/gnome-3-28-1804/145 loop4 7:4 0 51M 1 loop /snap/snap-store/498 loop5 7:5 0 31.1M 1 loop /snap/snapd/10707 loop6 7:6 0 31.1M 1 loop /snap/snapd/10492 loop7 7:7 0 51M 1 loop /snap/snap-store/518 loop8 7:8 0 161.4M 1 loop /snap/gnome-3-28-1804/128 loop9 7:9 0 55.4M 1 loop /snap/core18/1944 loop10 7:10 0 62.1M 1 loop /snap/gtk-common-themes/1506 loop11 7:11 0 219M 1 loop /snap/gnome-3-34-1804/66 loop12 7:12 0 217.9M 1 loop /snap/gnome-3-34-1804/60 loop13 7:13 0 64.8M 1 loop /snap/gtk-common-themes/1514 sda 8:0 0 20G 0 disk ├─sda1 8:1 0 512M 0 part /boot/efi ├─sda2 8:2 0 1K 0 part └─sda5 8:5 0 19.5G 0 part / sr0 11:0 1 1024M 0 rom
The lsblk command shows block storage devices, including partitions and mounted filesystems.
More options for lsblk:
$ lsblk --help Usage: lsblk [options] [<device> ...] List information about block devices. Options: -D, --discard print discard capabilities -E, --dedup <column> de-duplicate output by <column> -I, --include <list> show only devices with specified major numbers -J, --json use JSON output format -O, --output-all output all columns -P, --pairs use key="value" output format -S, --scsi output info about SCSI devices -T, --tree[=<column>] use tree format output -a, --all print all devices -b, --bytes print SIZE in bytes rather than in human readable format -d, --nodeps don't print slaves or holders -e, --exclude <list> exclude devices by major number (default: RAM disks) -f, --fs output info about filesystems -i, --ascii use ascii characters only -l, --list use list format output -M, --merge group parents of sub-trees (usable for RAIDs, Multi-path) -m, --perms output info about permissions -n, --noheadings don't print headings -o, --output <list> output columns -p, --paths print complete device path -r, --raw use raw output format -s, --inverse inverse dependencies -t, --topology output info about topology -z, --zoned print zone model -x, --sort <column> sort output by <column> --sysroot <dir> use specified directory as system root -h, --help display this help -V, --version display version Available output columns: NAME device name KNAME internal kernel device name PATH path to the device node MAJ:MIN major:minor device number FSAVAIL filesystem size available FSSIZE filesystem size FSTYPE filesystem type FSUSED filesystem size used FSUSE% filesystem use percentage MOUNTPOINT where the device is mounted LABEL filesystem LABEL UUID filesystem UUID PTUUID partition table identifier (usually UUID) PTTYPE partition table type PARTTYPE partition type UUID PARTLABEL partition LABEL PARTUUID partition UUID PARTFLAGS partition flags RA read-ahead of the device RO read-only device RM removable device HOTPLUG removable or hotplug device (usb, pcmcia, ...) MODEL device identifier SERIAL disk serial number SIZE size of the device STATE state of the device OWNER user name GROUP group name MODE device node permissions ALIGNMENT alignment offset MIN-IO minimum I/O size OPT-IO optimal I/O size PHY-SEC physical sector size LOG-SEC logical sector size ROTA rotational device SCHED I/O scheduler name RQ-SIZE request queue size TYPE device type DISC-ALN discard alignment offset DISC-GRAN discard granularity DISC-MAX discard max bytes DISC-ZERO discard zeroes data WSAME write same max bytes WWN unique storage identifier RAND adds randomness PKNAME internal parent kernel device name HCTL Host:Channel:Target:Lun for SCSI TRAN device transport type SUBSYSTEMS de-duplicated chain of subsystems REV device revision VENDOR device vendor ZONED zone model For more details see lsblk(8). - Browse the /dev directory for available special or device files.
$ ls /dev agpgart loop12 snapshot tty34 tty9 uhid autofs loop13 snd tty35 ttyprintk uinput block loop14 sr0 tty36 ttyS0 urandom bsg loop2 stderr tty37 ttyS1 userio btrfs-control loop3 stdin tty38 ttyS10 vcs bus loop4 stdout tty39 ttyS11 vcs1 cdrom loop5 tty tty4 ttyS12 vcs2 cdrw loop6 tty0 tty40 ttyS13 vcs3 char loop7 tty1 tty41 ttyS14 vcs4 console loop8 tty10 tty42 ttyS15 vcs5 core loop9 tty11 tty43 ttyS16 vcs6 cpu_dma_latency loop-control tty12 tty44 ttyS17 vcsa cuse mapper tty13 tty45 ttyS18 vcsa1 disk mcelog tty14 tty46 ttyS19 vcsa2 dma_heap mem tty15 tty47 ttyS2 vcsa3 dri mqueue tty16 tty48 ttyS20 vcsa4 dvd net tty17 tty49 ttyS21 vcsa5 ecryptfs null tty18 tty5 ttyS22 vcsa6 fb0 nvram tty19 tty50 ttyS23 vcsu fd port tty2 tty51 ttyS24 vcsu1 full ppp tty20 tty52 ttyS25 vcsu2 fuse psaux tty21 tty53 ttyS26 vcsu3 hidraw0 ptmx tty22 tty54 ttyS27 vcsu4 hpet pts tty23 tty55 ttyS28 vcsu5 hugepages random tty24 tty56 ttyS29 vcsu6 hwrng rfkill tty25 tty57 ttyS3 vfio initctl rtc tty26 tty58 ttyS30 vga_arbiter input rtc0 tty27 tty59 ttyS31 vhci kmsg sda tty28 tty6 ttyS4 vhost-net lightnvm sda1 tty29 tty60 ttyS5 vhost-vsock log sda2 tty3 tty61 ttyS6 vmci loop0 sda5 tty30 tty62 ttyS7 vsock loop1 sg0 tty31 tty63 ttyS8 zero loop10 sg1 tty32 tty7 ttyS9 zfs loop11 shm tty33 tty8 udmabuf
- Use dmidecode to view BIOS and system information.
$ sudo dmidecode # dmidecode 3.2 Getting SMBIOS data from sysfs. SMBIOS 2.7 present. 620 structures occupying 29060 bytes. Table at 0x000E0010. Handle 0x0000, DMI type 0, 24 bytes BIOS Information Vendor: Phoenix Technologies LTD Version: 6.00 Release Date: 07/22/2020 Address: 0xEA480 Runtime Size: 88960 bytes ROM Size: 64 kB Characteristics: ISA is supported PCI is supported PC Card (PCMCIA) is supported PNP is supported APM is supported BIOS is upgradeable BIOS shadowing is allowed ESCD support is available Boot from CD is supported Selectable boot is supported EDD is supported Print screen service is supported (int 5h) 8042 keyboard services are supported (int 9h) Serial services are supported (int 14h) Printer services are supported (int 17h) CGA/mono video services are supported (int 10h) ACPI is supported Smart battery is supported BIOS boot specification is supported Function key-initiated network boot is supported Targeted content distribution is supported BIOS Revision: 4.6 Firmware Revision: 0.0 Handle 0x0001, DMI type 1, 27 bytes System Information Manufacturer: VMware, Inc. Product Name: VMware Virtual Platform Version: None Serial Number: VMware-56 4d 6d 49 cc cb 86 de-d4 ca fa ad 4b cf 54 30 UUID: 496d4d56-cbcc-de86-d4ca-faad4bcf5430 Wake-up Type: Power Switch SKU Number: Not Specified Family: Not Specified ##### snipped
More options for dmidecode:
$ dmidecode --help Usage: dmidecode [OPTIONS] Options are: -d, --dev-mem FILE Read memory from device FILE (default: /dev/mem) -h, --help Display this help text and exit -q, --quiet Less verbose output -s, --string KEYWORD Only display the value of the given DMI string -t, --type TYPE Only display the entries of given type -H, --handle HANDLE Only display the entry of given handle -u, --dump Do not decode the entries --dump-bin FILE Dump the DMI data to a binary file --from-dump FILE Read the DMI data from a binary file --no-sysfs Do not attempt to read DMI data from sysfs files --oem-string N Only display the value of the given OEM string -V, --version Display the version and exit - Explore sysfs for hardware devices and related kernel information.
$ cat /sys/class/power_supply/ACAD/type Mains
- Inspect the /proc and /sys directories for additional hardware details.
$ cat /proc/meminfo MemTotal: 4000788 kB MemFree: 2435468 kB MemAvailable: 2901532 kB Buffers: 50048 kB Cached: 585872 kB SwapCached: 0 kB Active: 803460 kB Inactive: 345520 kB Active(anon): 514404 kB Inactive(anon): 768 kB Active(file): 289056 kB Inactive(file): 344752 kB Unevictable: 16 kB Mlocked: 16 kB SwapTotal: 945416 kB SwapFree: 945416 kB Dirty: 232 kB Writeback: 0 kB AnonPages: 513136 kB Mapped: 243012 kB Shmem: 2116 kB KReclaimable: 73988 kB Slab: 187708 kB SReclaimable: 73988 kB SUnreclaim: 113720 kB KernelStack: 10144 kB PageTables: 10984 kB NFS_Unstable: 0 kB Bounce: 0 kB WritebackTmp: 0 kB CommitLimit: 2945808 kB Committed_AS: 3216804 kB VmallocTotal: 34359738367 kB VmallocUsed: 24172 kB VmallocChunk: 0 kB Percpu: 94720 kB HardwareCorrupted: 0 kB AnonHugePages: 0 kB ShmemHugePages: 0 kB ShmemPmdMapped: 0 kB FileHugePages: 0 kB FilePmdMapped: 0 kB HugePages_Total: 0 HugePages_Free: 0 HugePages_Rsvd: 0 HugePages_Surp: 0 Hugepagesize: 2048 kB Hugetlb: 0 kB DirectMap4k: 276288 kB DirectMap2M: 2869248 kB DirectMap1G: 3145728 kB
The /proc and /sys directories contain real-time and persistent system and hardware data, which can be accessed using the cat command.
- Use dmesg to view kernel diagnostic messages and search for related hardware information.
$ dmesg [ 0.000000] Linux version 5.8.0-41-generic (buildd@lgw01-amd64-003) (gcc (Ubuntu 9.3.0-17ubuntu1~20.04) 9.3.0, GNU ld (GNU Binutils for Ubuntu) 2.34) #46~20.04.1-Ubuntu SMP Mon Jan 18 17:52:23 UTC 2021 (Ubuntu 5.8.0-41.46~20.04.1-generic 5.8.18) [ 0.000000] Command line: BOOT_IMAGE=/boot/vmlinuz-5.8.0-41-generic root=UUID=8e7d73f3-e847-46a2-abcd-f505ec2a73f7 ro quiet splash [ 0.000000] KERNEL supported cpus: [ 0.000000] Intel GenuineIntel [ 0.000000] AMD AuthenticAMD [ 0.000000] Hygon HygonGenuine [ 0.000000] Centaur CentaurHauls [ 0.000000] zhaoxin Shanghai [ 0.000000] Disabled fast string operations [ 0.000000] x86/fpu: Supporting XSAVE feature 0x001: 'x87 floating point registers' [ 0.000000] x86/fpu: Supporting XSAVE feature 0x002: 'SSE registers' [ 0.000000] x86/fpu: Supporting XSAVE feature 0x004: 'AVX registers' [ 0.000000] x86/fpu: xstate_offset[2]: 576, xstate_sizes[2]: 256 [ 0.000000] x86/fpu: Enabled xstate features 0x7, context size is 832 bytes, using 'compacted' format. [ 0.000000] BIOS-provided physical RAM map: [ 0.000000] BIOS-e820: [mem 0x0000000000000000-0x000000000009e7ff] usable [ 0.000000] BIOS-e820: [mem 0x000000000009e800-0x000000000009ffff] reserved [ 0.000000] BIOS-e820: [mem 0x00000000000dc000-0x00000000000fffff] reserved [ 0.000000] BIOS-e820: [mem 0x0000000000100000-0x00000000bfecffff] usable [ 0.000000] BIOS-e820: [mem 0x00000000bfed0000-0x00000000bfefefff] ACPI data ##### snipped
More options for dmesg:
$ dmesg --help Usage: dmesg [options] Display or control the kernel ring buffer. Options: -C, --clear clear the kernel ring buffer -c, --read-clear read and clear all messages -D, --console-off disable printing messages to console -E, --console-on enable printing messages to console -F, --file <file> use the file instead of the kernel log buffer -f, --facility <list> restrict output to defined facilities -H, --human human readable output -k, --kernel display kernel messages -L, --color[=<when>] colorize messages (auto, always or never) colors are enabled by default -l, --level <list> restrict output to defined levels -n, --console-level <level> set level of messages printed to console -P, --nopager do not pipe output into a pager -p, --force-prefix force timestamp output on each line of multi-line messages -r, --raw print the raw message buffer -S, --syslog force to use syslog(2) rather than /dev/kmsg -s, --buffer-size <size> buffer size to query the kernel ring buffer -u, --userspace display userspace messages -w, --follow wait for new messages -x, --decode decode facility and level to readable string -d, --show-delta show time delta between printed messages -e, --reltime show local time and time delta in readable format -T, --ctime show human-readable timestamp (may be inaccurate!) -t, --notime don't show any timestamp with messages --time-format <format> show timestamp using the given format: [delta|reltime|ctime|notime|iso] Suspending/resume will make ctime and iso timestamps inaccurate. -h, --help display this help -V, --version display version Supported log facilities: kern - kernel messages user - random user-level messages mail - mail system daemon - system daemons auth - security/authorization messages syslog - messages generated internally by syslogd lpr - line printer subsystem news - network news subsystem Supported log levels (priorities): emerg - system is unusable alert - action must be taken immediately crit - critical conditions err - error conditions warn - warning conditions notice - normal but significant condition info - informational debug - debug-level messages For more details see dmesg(1).
Author: Mohd
Shakir Zakaria
Mohd Shakir Zakaria is a cloud architect with deep roots in software development and open-source advocacy. Certified in AWS, Red Hat, VMware, ITIL, and Linux, he specializes in designing and managing robust cloud and on-premises infrastructures.
Mohd Shakir Zakaria is a cloud architect with deep roots in software development and open-source advocacy. Certified in AWS, Red Hat, VMware, ITIL, and Linux, he specializes in designing and managing robust cloud and on-premises infrastructures.
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