Dmesg
From Wikipedia, the free encyclopedia
- The correct title of this article is dmesg. The initial letter is shown capitalized due to technical restrictions.
dmesg (for "diagnostic message") is a command on Unix-like operating systems that prints the message buffer of the kernel. This buffer contains a variety of important messages from those printed during boot to those used for debugging software. This information may also be stored to disk via a logging daemon, such as syslog.
dmesg is often piped to tail for an easier overview of recent events:
dmesg | tail
Example output on a Linux system:
Linux version 2.6.17.11 (root@gateway) (gcc version 3.4.5) #2 Mon Sep 4 11:21:13 EST 2006
BIOS-provided physical RAM map:
BIOS-e820: 0000000000000000 - 00000000000a0000 (usable)
BIOS-e820: 00000000000f0000 - 0000000000100000 (reserved)
BIOS-e820: 0000000000100000 - 0000000004800000 (usable)
BIOS-e820: 00000000ffff0000 - 0000000100000000 (reserved)
72MB LOWMEM available.
On node 0 totalpages: 18432
DMA zone: 4096 pages, LIFO batch:0
Normal zone: 14336 pages, LIFO batch:3
DMI 2.0 present.
Allocating PCI resources starting at 10000000 (gap: 04800000:fb7f0000)
Built 1 zonelists
Kernel command line: auto BOOT_IMAGE=Linux ro root=301
Initializing CPU#0
PID hash table entries: 512 (order: 9, 2048 bytes)
Detected 150.002 MHz processor.
Using tsc for high-res timesource
Console: colour VGA+ 80x25
Dentry cache hash table entries: 16384 (order: 4, 65536 bytes)
Inode-cache hash table entries: 8192 (order: 3, 32768 bytes)
Memory: 69632k/73728k available (1903k kernel code, 3644k reserved, 728k data, 140k init, 0k highmem)
Checking if this processor honours the WP bit even in supervisor mode... Ok.
Calibrating delay using timer specific routine.. 300.47 BogoMIPS (lpj=1502375)
Mount-cache hash table entries: 512
CPU: After generic identify, caps: 008001bf 00000000 00000000 00000000 00000000 00000000 00000000
CPU: After vendor identify, caps: 008001bf 00000000 00000000 00000000 00000000 00000000 00000000
Intel Pentium with F0 0F bug - workaround enabled.
CPU: After all inits, caps: 008001bf 00000000 00000000 00000000 00000000 00000000 00000000
CPU: Intel Pentium MMX stepping 03
Checking 'hlt' instruction... OK.
SMP alternatives: switching to UP code
Freeing SMP alternatives: 0k freed
NET: Registered protocol family 16
PCI: PCI BIOS revision 2.10 entry at 0xfb240, last bus=0
Setting up standard PCI resources
Linux Plug and Play Support v0.97 (c) Adam Belay
PnPBIOS: Scanning system for PnP BIOS support...
PnPBIOS: Found PnP BIOS installation structure at 0xc00fbf30
PnPBIOS: PnP BIOS version 1.0, entry 0xf0000:0xbf58, dseg 0xf0000
PnPBIOS: 14 nodes reported by PnP BIOS; 14 recorded by driver
SCSI subsystem initialized
PCI: Probing PCI hardware
PCI: Probing PCI hardware (bus 00)
PCI quirk: region 4f00-4f3f claimed by PIIX4 ACPI
PCI quirk: region 5f00-5f0f claimed by PIIX4 SMB
Boot video device is 0000:00:09.0
TC classifier action (bugs to netdev@vger.kernel.org cc hadi@cyberus.ca)
pnp: 00:09: ioport range 0x208-0x20f has been reserved
NET: Registered protocol family 2
IP route cache hash table entries: 1024 (order: 0, 4096 bytes)
TCP established hash table entries: 4096 (order: 2, 16384 bytes)
TCP bind hash table entries: 2048 (order: 1, 8192 bytes)
TCP: Hash tables configured (established 4096 bind 2048)
TCP reno registered
apm: BIOS version 1.2 Flags 0x07 (Driver version 1.16ac)
io scheduler noop registered
io scheduler cfq registered (default)
Limiting direct PCI/PCI transfers.
isapnp: Scanning for PnP cards...
isapnp: Card 'ESS ES1868 Plug and Play AudioDrive'
isapnp: 1 Plug & Play card detected total
lp: driver loaded but no devices found
Real Time Clock Driver v1.12ac
Non-volatile memory driver v1.2
Serial: 8250/16550 driver $Revision: 1.90 $ 4 ports, IRQ sharing disabled
serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
serial8250: ttyS1 at I/O 0x2f8 (irq = 3) is a 16550A
00:0a: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
00:0d: ttyS1 at I/O 0x2f8 (irq = 3) is a 16550A
parport: PnPBIOS parport detected.
parport0: PC-style at 0x378, irq 7 [PCSPP]
lp0: using parport0 (interrupt-driven).
RAMDISK driver initialized: 16 RAM disks of 4096K size 1024 blocksize
loop: loaded (max 8 devices)
nbd: registered device at major 43
ne2k-pci.c:v1.03 9/22/2003 D. Becker/P. Gortmaker
http://www.scyld.com/network/ne2k-pci.html
eth0: RealTek RTL-8029 found at 0x6500, IRQ 10, 00:00:B4:A2:4B:6E.
eth1: RealTek RTL-8029 found at 0x6600, IRQ 9, 00:00:E8:DA:7E:72.
PPP generic driver version 2.4.2
PPP Deflate Compression module registered
PPP BSD Compression module registered
NET: Registered protocol family 24
Uniform Multi-Platform E-IDE driver Revision: 7.00alpha2
ide: Assuming 33MHz system bus speed for PIO modes; override with idebus=xx
PIIX4: IDE controller at PCI slot 0000:00:07.1
PIIX4: chipset revision 1
PIIX4: not 100% native mode: will probe irqs later
ide0: BM-DMA at 0xf000-0xf007, BIOS settings: hda:pio, hdb:pio
ide1: BM-DMA at 0xf008-0xf00f, BIOS settings: hdc:pio, hdd:pio
Probing IDE interface ide0...
hda: QUANTUM FIREBALL1280A, ATA DISK drive
ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
Probing IDE interface ide1...
hda: max request size: 128KiB
hda: 2503872 sectors (1281 MB) w/83KiB Cache, CHS=2484/16/63, DMA
hda: hda1 hda2
PNP: PS/2 Controller [PNP0303] at 0x60,0x64 irq 1
PNP: PS/2 controller doesn't have AUX irq; using default 12
serio: i8042 AUX port at 0x60,0x64 irq 12
serio: i8042 KBD port at 0x60,0x64 irq 1
mice: PS/2 mouse device common for all mice
input: PC Speaker as /class/input/input0
input: AT Translated Set 2 keyboard as /class/input/input1
Advanced Linux Sound Architecture Driver Version 1.0.11rc4 (Wed Mar 22 10:27:24 2006 UTC).
pnp: Device 01:01.00 activated.
pnp: Device 01:01.01 activated.
es1688: can't grab port 0x224
ALSA device list:
#0: ESS AudioDrive ES1868 at 0x220, irq 5, dma1 1, dma2 3
GACT probability NOT on
Mirror/redirect action on
u32 classifier
input device check on
Actions configured
Netfilter messages via NETLINK v0.30.
IPv4 over IPv4 tunneling driver
ip_conntrack version 2.4 (576 buckets, 4608 max) - 224 bytes per conntrack
ctnetlink v0.90: registering with nfnetlink.
ip_conntrack_pptp version 3.1 loaded
ip_nat_pptp version 3.0 loaded
ip_tables: (C) 2000-2006 Netfilter Core Team
ipt_recent v0.3.1: Stephen Frost <sfrost@snowman.net>. http://snowman.net/projects/ipt_recent/
ClusterIP Version 0.8 loaded successfully
TCP bic registered
NET: Registered protocol family 1
NET: Registered protocol family 17
Using IPI Shortcut mode
ReiserFS: hda1: found reiserfs format "3.6" with standard journal
ReiserFS: hda1: using ordered data mode
ReiserFS: hda1: journal params: device hda1, size 8192, journal first block 18, max trans len 1024, max batch 900, max commit age 30, max trans age 30
ReiserFS: hda1: checking transaction log (hda1)
ReiserFS: hda1: replayed 1 transactions in 0 seconds
ReiserFS: hda1: Using r5 hash to sort names
VFS: Mounted root (reiserfs filesystem) readonly.
Freeing unused kernel memory: 140k freed
Adding 143128k swap on /dev/hda2. Priority:-1 extents:1 across:143128k
