SUSE LINUX Enterprise Server – Installation and Administration
Chapter 28. System Monitoring Utilities / 28.9. Kernel Ring Buffer: dmesg
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28.9. Kernel Ring Buffer: dmesg

The Linux kernel keeps certain messages in a ring buffer. To view these messages, enter the command dmesg: 

$ dmesg
[...]
sdc : READ CAPACITY failed.
sdc : status = 1, message = 00, host = 0, driver = 08
Info fld=0xa00 (nonstd), Current sd00:00: sense key Not Ready
sdc : block size assumed to be 512 bytes, disk size 1GB.
sdc: test WP failed, assume Write Enabled
 sdc: I/O error: dev 08:20, sector 0
 I/O error: dev 08:20, sector 0
 I/O error: dev 08:20, sector 2097144
 I/O error: dev 08:20, sector 2097144
 I/O error: dev 08:20, sector 0
 I/O error: dev 08:20, sector 0
 unable to read partition table
 I/O error: dev 08:20, sector 0
nfs: server totan not responding, still trying
nfs: server totan OK

The last line indicates that there is a temporary problem in the NFS server totan. The lines up to that point are triggered by the insertion of a USB memory stick.

Older events are logged in the files /var/log/messages and /var/log/warn.

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