network traffic prints in console @ slack 13

deleb · 03-24-2010, 05:37 PM

I've been using slackware since slack12.2 on a linux box as router at home with some servers running on it and it's been awesome and performs perfectly. But since I upgraded to slackware 13 there is something that drives me crazy.

I use to manage the box through SSH but sometimes I have to do some configs localy and it's almost impossible because I have constant echos of some traffic the iptables is forwarding to other hosts on the network. I googled a lot (since slack13 went out...) and tried many things but I can't find how to disable this maddness spam I'm getting :P

Any help/guidance will be much appreciated!!!

mRgOBLIN · 03-24-2010, 06:08 PM

It is most likely something that has been changed in /etc/syslog.conf

See what (if anything) is set to send messages to /dev/console

GazL · 03-24-2010, 08:58 PM

You could always just ignore the first virtual console and alt-f2 and use the second one. It's what I do to avoid being interrupted by console messages.

deleb · 03-25-2010, 07:43 AM

Quote:

Originally Posted by mRgOBLIN

It is most likely something that has been changed in /etc/syslog.conf

I'll check that out... (I'm not home right now)

Quote:

Originally Posted by mRgOBLIN

See what (if anything) is set to send messages to /dev/console

How can I do this?

Quote:

Originally Posted by GazL

You could always just ignore the first virtual console and alt-f2 and use the second one. It's what I do to avoid being interrupted by console messages.

It doesn't matter, it prints on every console :P

Thanks for the help!

GazL · 03-25-2010, 08:19 AM

It was worth a shot!

I've never had that problem.

My understanding is that /dev/tty0 will write to whichever virtual console you're using at the time. Perhaps you've got something writing to /dev/tty0 that you can change to use /dev/tty1, or any of the other specific ttys.

ponce · 03-25-2010, 11:14 AM

you can alternatively try setting a lower error level when launching klogd in /etc/rc.d/rc.syslog modifying the line

Code:

    /usr/sbin/klogd -c 3 -x

to

Code:

    /usr/sbin/klogd -c 1 -x

and then restart syslog

Code:

/etc/rc.d/rc.syslog restart

from klogd man page:

Quote:

If kernel messages are directed through the syslogd daemon the klogd daemon, as of version 1.1, has the ability to properly prioritize kernel messages. Prioritization of the kernel messages was added to it at approximately version 0.99pl13 of the kernel. The raw kernel messages are of the form:

<[0-7]>Something said by the kernel.
The priority of the kernel message is encoded as a single numeric digit enclosed inside the <> pair. The definitions of these values is given in the kernel include file kernel.h. When a message is received from the kernel the klogd daemon reads this priority level and assigns the appropriate priority level to the syslog message. If file output (-f) is used the prioritization sequence is left pre-pended to the kernel message.

The klogd daemon also allows the ability to alter the presentation of kernel messages to the system console. Consequent with the prioritization of kernel messages was the inclusion of default messaging levels for the kernel. In a stock kernel the the default console log level is set to 7. Any messages with a priority level numerically lower than 7 (higher priority) appear on the console.

Messages of priority level 7 are considered to be 'debug' messages and will thus not appear on the console. Many administrators, particularly in a multi-user environment, prefer that all kernel messages be handled by klogd and either directed to a file or to the syslogd daemon. This prevents 'nuisance' messages such as line printer out of paper or disk change detected from cluttering the console.

When -c is given on the commandline the klogd daemon will execute a system call to inhibit all kernel messages from being displayed on the console. Former versions always issued this system call and defaulted to all kernel messages except for panics. This is handled differently nowardays so klogd doesn't need to set this value anymore. The argument given to the -c switch specifies the priority level of messages which will be directed to the console. Note that messages of a priority value LOWER than the indicated number will be directed to the console.
For example, to have the kernel display all messages with a priority level of 3 (KERN_ERR) or more severe the following command would be executed:
klogd -c 4
The definitions of the numeric values for kernel messages are given in the file kernel.h which can be found in the /usr/include/linux directory if the kernel sources are installed. These values parallel the syslog priority values which are defined in the file syslog.h found in the /usr/include/sys sub-directory.

deleb · 03-26-2010, 05:56 PM

I just finished reinstalling the whole system cause I updated the hdd and some other hardware and after setting all the configs I'm not getting this messages anymore. Now I want this to appear again so I can find what it was....

The error level is at it's default (3) so that should not be it...

I think the rc.ip_forward might had something to do with it because I used to use it before switching to firehol to make all the iptables rules...

Anyways, thanks everyone for the help!