Why ue0 do ARP on non local address when using static route?

[Chuck Swiger]

On Feb 13, 2013, at 12:35 PM, Jin Guojun wrote:
> When attached a Trendent TU2-ET100 USB Ether dongle for a second interface, it 
> has no problem to talk to the local network (10.234.37.0/24), but it has problem 
> to talk to a remote network or host (10.227.148.0/24) via eu0 interface.
> When a remote host ping this host or this host ping that remote host, ARP 
> request is always showing up.
> A static route is set and remote host is no part of the local sub net, why ARP 
> is going on?

You've told the interface that it can reach 10.227.148.52 via 10.234.37.80, which is
the IP ue0 was configured to use.  It sends ARPOP_REQUESTS to get the MAC address of
10.227.148.52 which is expected to be reachable.

> Is any sysctl parameter can fix this problem?

You can do things like use proxy-arp, or setup /etc/ethers, or NAT, or even configure
ue0 to be on the same subnet as 10.227.148.52 instead, perhaps using an alias.

Regards,
-- 
-Chuck