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# Linux dmesg Command [ Linux Command Manual](#) The Linux dmesg (English full name: display message) command is used to display boot messages. The kernel stores boot messages in a ring buffer. If you don't have time to view the messages during boot, you can use dmesg to view them. Boot messages are also saved in a file named dmesg in the /var/log directory. ### Syntax dmesg **Parameter Description**: * -c Clear the contents of the ring buffer after displaying the information. * -s Default is 8196, which is exactly equal to the size of the ring buffer. * -n Set the level of recorded information. ### Examples Display boot messages # dmesg |less WARNING: terminal is not fully functional [ 0.000000] Initializing cgroup subsys cpuset [ 0.000000] Initializing cgroup subsys cpu [ 0.000000] Linux version 2.6.32-21-generic (buildd@rothera) (gcc version 4.4.3 (Ub untu 4.4.3-4ubuntu5) ) #32-Ubuntu SMP Fri Apr 16 08:10:02 UTC 2010 (Ubuntu 2.6.32-21.32-generic 2.6.32.11+drm33.2)[ 0.000000] KERNEL supported cpus:[ 0.000000] Intel GenuineIntel[ 0.000000] AMD AuthenticAMD[ 0.000000] NSC Geode by NSC [ 0.000000] Cyrix CyrixInstead[ 0.000000] Centaur CentaurHauls[ 0.000000] Transmeta GenuineTMx86[ 0.000000] Transmeta TransmetaCPU[ 0.000000] UMC UMC UMC UMC [ 0.000000] BIOS-provided physical RAM map:[ 0.000000] BIOS-e820: 0000000000000000 - 000000000009f800 (usable)[ 0.000000] BIOS-e820: 000000000009f800 - 00000000000a0000 (reserved)[ 0.000000] BIOS-e820: 00000000000ca000 - 00000000000cc000 (reserved)[ 0.000000] BIOS-e820: 00000000000dc000 - 00000000000e0000 (reserved)[ 0.000000] BIOS-e820: 00000000000e4000 - 0000000000100000 (reserved)[ 0.000000] BIOS-e820: 0000000000100000 - 000000003fef0000 (usable)[ 0.000000] BIOS-e820: 000000003fef0000 - 000000003feff000 (ACPI data)[ 0.000000] BIOS-e820: 000000003feff000 - 000000003ff00000 (ACPI NVS)……Some content is omitted Display boot messages #pwd //Check current directory/home/hnlinux/# dmesg > boot.msg //Save boot information to boot.msgIn the file#ls //Show the boot file in the current directory.msg [ Linux Command Manual](#)