[Strange behavior with arp permanent entries]

[Jim Long]

On Sat, Feb 10, 2007 at 07:33:30PM +0200, ea at sellinet.net wrote:
> 
> I'm trying to restrict some LAN access by arp permanent entries. But it
> didn't work or it didn't work as I realize it. For example I have the
> following perm entries:
> 
> user1: (82.199.215.195) at 00:0f:ea:a4:60:c5 on vlan804 permanent [vlan]
> user2: (82.199.215.196) at 00:13:8f:b1:68:4b on vlan804 permanent [vlan]
> 
> And from what I realize if the user1 attempts to use user2's IP address.
> The Router should block all packets which coming from wrong physical
> address. But actually that didn't happen and user1 can use user2's IP
> address without any problems.

Have you tried using 'staticarp' in this interface's ifconfig(8) 
settings?  If you turn on staticarp, you'll probably need to specify 
arp entries for ALL hosts on that interface -- or at least, all the 
ones you care about.

HTH,

Jim