netconsole after boot

Peter Hüwe PeterHuewe at
Wed Aug 26 10:58:06 UTC 2009

Am Mittwoch 26 August 2009 07:17:18 schrieb hong zhang:
> What do you mean 'printks'?
> After 'dmesg -n 8', remote PC displays
> same as local dmesg.

Okay - it is like I expected :)
Try the following on a local pc - replace ppdev with whatever module you like 
* switch to first console (<ctrl+alt+f1>) 
* login as root
* and insert your kernel module
I guess it will look something like this

kerneldev # modprobe ppdev
kerneldev #
-> No output on the console, but a message in dmesg.

Now unload the driver again and set the console_loglevel to 8 and repeat the 
steps - now it will look like:
kerneldev # rmmod ppdev
kerneldev # dmesg -n8
kerneldev # modprobe ppdev
ppdev: user-space parallel port driver
kerneldev #

So the kernel-messages start to appear on the console - 
The console_loglevel affects this behaviour - setting it to 8 will print all 
kind of messages to the console.

When you load the netconsole module - those console messages will be 
redirected to the network --> the netconsole will print every kernel-message 
that has a higher priority (i.e. a lower number) than the console_loglevel

You can set the console_loglevel in /etc/sysctl.conf

Best regards,

More information about the devel mailing list