[CentOS] sysctl -p at startup?

Tue Jan 8 13:57:48 UTC 2013
Mike Burger <mburger at bubbanfriends.org>

> On 2 January 2013 17:54, Emmett Culley <emmett at webengineer.com> wrote:
>> I understand that the contents of /etc/sysctl.conf should be read and
>> executed at system startup.  However that never happens and I have to
>> run
>> sysctl -p after every reboot to get the settings I want.
>> This is happening on every CentOS machine and VM I have.   I can see in
>> the startup scripts that "sysctl -e -p /etc/sysctl.conf >/dev/null 2>&1"
>>   is run at start up by the "apply_sysctl" function, yet the settings
>> are
>> never correct unless I run sysctl -p on the command line.
>> Anybody know why that would be?
>> It depends on whether the changes you are making using sysctl are being
> affected by other processes later on in the startup sequence
> I have to run sysctl -p manually in order to stop kernel messages being
> printed to the console as even though i have them configured off in my
> sysctl this is overridden at some other point and i get to find out all
> about SoftMAC and its scanning ways
> https://bugzilla.redhat.com/show_bug.cgi?id=760497


Just on a hunch, check your /etc/rsyslog.conf file and look for:

# Log all kernel messages to the console.
# Logging much else clutters up the screen.
kern.*                                                 /dev/console

If you see that, comment it out, reload rsyslog and that should take care
of it.

You can also play with some rules in rsyslog that can redirect the kernel
output to wherever you like...or even specific kernel output (iptables,
etc.) to various logs or even /dev/null :-)
Mike Burger

"It's always suicide-mission this, save-the-planet that. No one ever just
stops by to say 'hi' anymore." --Colonel Jack O'Neill, SG1