Re: Packet Tracing (linux klog patch)

[abial () WEBGIRO COM (Andrzej Bialecki)]

On Sat, 12 Feb 2000, Dragos Ruiu wrote:

> How to use it:
> -This patch makes the kernel log all ethernet packets to syslog.
> -The logging happens at the default level.  I.e. normally on.
> -You can turn logging on and off at the console by using the Magic SysRq key
>  and a number to change the logging level.
> -Put the interface into promiscuous mode: ifconfig eth0 promisc
>
> Notes:
> -It makes a neat hotkey sniffer when using the text console too.
> -It seems to run pretty fast. Any benchmark data welcome(-->dr () dursec com).
> -try a tail -f /var/log/messages for real time display

I was wondering... Are you sure it doesn't overrun the kernel message
buffer? I noticed that sometimes, when you produce tons of messages from
within the kernel, some of them are lost.

I would rather use package as NeTraMet for doing this - it also does very
nice traffic compression in the form of flows - very fast, extremely
flexible, uses standard libpcap, doesn't require kernel patching etc...

Andrzej Bialecki

//  <abial () webgiro com> WebGiro AB, Sweden (http://www.webgiro.com)
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