I'm using Debian Squeeze on a Dell Latitude E6500. Everytime I suspend and wakeup my notebook I see some low-level kernel error messages on the console. They are harmless but I simply don’t want them displayed at all. /etc/sysctl.conf contains this section:
# Uncomment the following to stop low-level messages on console
# kernel.printk=3 4 1 3
I uncommented it and run “/etc/init.d/procps restart” and then these settings are correctly set (A cat /proc/sys/kernel/printk returns “3 4 1 3”) and the kernel messages are not displayed anymore. This is enough prove for me that I configured /etc/sysctl.conf correctly. But after a fresh reboot of my machine the settings in /proc/sys are back to “4 4 1 3” and I have to set them manually again to the right values (Or restart procps again).
What’s going wrong here? /etc/init.d/procps is linked in /etc/rcS.d so it is running on startup. Is there another program which could overwrite the printk values?
I encountered a similar problem some time ago. It was puzzling until we discovered that another file in /etc/sysctl.d/ was present and changed the same settings as /etc/sysctl.conf, but was sourced after so took precedence. Maybe it is also what’s happening on your box ?