running out of arp-cache

[Henning Fehrmann]

Hi Thomas,

On Thu, Apr 23, 2009 at 08:01:05PM +0200, Thomas Lange wrote:
> >>>>> On Tue, 21 Apr 2009 10:41:43 +0200, Henning Fehrmann <henning.fehrmann at aei.mpg.de> said:
> 
>     > Do you know the right kernel boot parameter to manipulate the arp cache?
> 
>     > If this is not possible, one should do it in the live-initrd or, latest,
>     > in the nfs-chroot environment. Currently, I am not sure whether one runs into
>     > problems already in the initrd.  
>     > Is there a generic way to add a proper
>     > /etc/sysctl.conf in the initrd or in the NFS-chroot, configured
>     > somewhere in the make-fai-nfsroot.conf? 
> 
> You could call /etc/init.d/procps start
> which is also the way it's done during booting a normal system.
Thank you.

This would imply that the /etc/sysctl.conf is already filled with the
right values. We have far more than 1024 nodes in the network. The
filling can be done by a proper make-fai-nfsroot hook. BTW, I did not
find much documentation about this which might be my fault. Does it
work as the usual FAI hooks?

I got this warning message already in the live initrd. It might help to 
write a script for the initrd which echos a reasonable cache sizes
values into 
/proc/sys/net/ipv4/neigh/default/gc_thresh1-3

Cheers,
Henning