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Dmesg

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'''dmesg''' displays the system message buffer. It's output is just like /var/run/dmesg.boot, although '''dmesg''' displays things that occur after boot as well. It can be helpful in tracking down problems that might not otherwise be noticed.  
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'''dmesg''' displays the contents of /var/run/dmesg.boot file which is populated during the boot process with the white high intense master console messages you see rolling by during the boot which are the results from the motherboard hardware inspection [POST].<br>
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<br>
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'''dmesg -a''' displays the the same as above plus the non-intense messages of started applications from /etc/rc.conf.
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It can be helpful in tracking down the BDS hardware device names for thing like disk drives and network interfaces.  
  
 
For example:
 
For example:
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  '''> dmesg'''
 
  '''> dmesg'''
 
  [snip]
 
  [snip]
  ad0: 194481MB <Maxtor 6B200R0/BAH41BM0> [395136/16/63] at ata0-master UDMA133
+
  ad0: 194481MB <Maxtor BAH41> [395136/16/63] at ata0-master UDMA133
  ad1: 194481MB <Maxtor 6B200P0/BAH41BM0> [395136/16/63] at ata0-slave UDMA133
+
  ad1: 194481MB <Maxtor BAH41> [395136/16/63] at ata0-slave UDMA133
 
  acd0: DVDR <SONY DVD RW DRU-500A/2.1a> at ata1-slave PIO4
 
  acd0: DVDR <SONY DVD RW DRU-500A/2.1a> at ata1-slave PIO4
 
  ad1: WARNING - WRITE_DMA UDMA ICRC error (retrying request) LBA=3205439
 
  ad1: WARNING - WRITE_DMA UDMA ICRC error (retrying request) LBA=3205439

Revision as of 19:58, 9 August 2012

dmesg displays the contents of /var/run/dmesg.boot file which is populated during the boot process with the white high intense master console messages you see rolling by during the boot which are the results from the motherboard hardware inspection [POST].

dmesg -a displays the the same as above plus the non-intense messages of started applications from /etc/rc.conf.

It can be helpful in tracking down the BDS hardware device names for thing like disk drives and network interfaces.

For example:

> dmesg
[snip]
ad0: 194481MB <Maxtor BAH41> [395136/16/63] at ata0-master UDMA133
ad1: 194481MB <Maxtor BAH41> [395136/16/63] at ata0-slave UDMA133
acd0: DVDR <SONY DVD RW DRU-500A/2.1a> at ata1-slave PIO4
ad1: WARNING - WRITE_DMA UDMA ICRC error (retrying request) LBA=3205439

Or:

> dmesg
[snip]
Mounting root from ufs:/dev/ad0s1a
pid 6152 (audacity), uid 1001: exited on signal 11 (core dumped)
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