## Auto-converted by kwiki2moinmoin v2005-10-07
~-Translation(s): [[it/dmesg|Italiano]] -~
----
Upon boot, the dmesg output is from the kernel booting, showing the devices it has found and if it has been able to configure them at all (aside from userland configuration). This log is also available in the file /var/log/dmesg.

The program helps users to print  out  their  bootup  messages.   Instead of copying the messages by hand, the user need only:{{{
              dmesg > boot.messages
}}}

and mail the boot.messages file to whoever can debug their problem.

You can use

dmesg | [[more]]

If you're getting error:

{{{dmesg: read kernel buffer failed: Operation not permitted}}}

you can run as root user:

{{{# echo 0 > /proc/sys/kernel/dmesg_restrict}}}

to relax dmesg buffer reads ( kernel compile option CONFIG_SECURITY_DMESG_RESTRICT )


 * [[http://linuxgazette.net/issue59/nazario.html|dmesg explained]].
 * [[http://www.rt.com/man/syslogd.8.html|Syslogd]].
 * [[https://www.kernel.org/doc/Documentation/sysctl/kernel.txt|sysctl kernel]]