arplookup x.x.x.x failed: host is not on local network

[Stefan Lambrev]

Hi,

Peter Jeremy wrote:
> I'm occasionally seeing pairs of messages like the following on
> my NAT host:
> arplookup 192.168.181.114 failed: host is not on local network
> arpresolve: can't allocate route for 192.168.181.114
>   
Normally this happens in badly configured LAN.

Lets say we have two hosts in the same physical network (same switch for 
example)
Host1 is configured 192.168.1.33/24 and Hosts2 have 192.168.1.1/30

Now when a broadcast or other packet is sent from Host1 it can reach 
Host2 without a problem.
But when Host2 try reach directly Host1 it doesn't know how and from 
here - can't allocate route  ...
I bet 192.168.181.114 have a wrong network mask ;)
> In my particular configuration, there are dual subnets between the NAT
> and target host.  My initial assumption was that the request was
> arriving on the other subnet and I added if_xname to the arplookup
> printf() - but that shows that interface matches the IP address.
> I've looked back through the mailing lists but the previous reports
> of this problem don't match my scenario.
>
> I've seen this with FreeBSD 5.3, 6.2 and 7.0.
>
> The (in)frequency of the problem makes me wonder if it's actually a
> resource exhaustion problem.
>
> Has anyone got any suggestions?
>
>   

-- 

Best Wishes,
Stefan Lambrev
ICQ# 24134177