Code Red

> Jeff Ogden wrote:
> > is causing network problems due to heavy ARP loads when the local
> > site routers ARP for what turn out to be unused IP addresses. This
> > is an issue when there are large blocks of IP addresses behind a
> > router. It is less of a problem when there is a relatively small
> > number of IP addresses behind a router (say one class C worth). Are
> > others seeing these sorts of problems? What strategies are there for
> > dealing with this?

Use smaller subnets (possibly vlans etc) !


I don't clearly see how this will help.

you said you had large numbers of unused IP addresses.

split the block down into manageable chunks, send the chunks to the
relevant interfaces and route the whole netblock to null

your used ips go out to their appropriate networks and the unused ones
having nowhere to go get sent to null.

So: No ARPs to spare netblocks!

by splitting it into subnets you will also reduce the amuont of broadcast
traffic on the network, (each bad ip will generate several broadcast arp

And: Better network performance, improved bandwidth!