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Re: Static interface routes for IP address on different subnet doesn't send an ARP who-has

In article <>, Peter Kieser  
<> wrote:
>I have an ISP that requires that I use a subnet mask of 
>(/32) which requires that I add a static interface route for the gateway 
>IP address because it's on a different subnet 
>( In Linux and FreeBSD this works as 
>intended, and the network stack sends an ARP request for the gateway IP 
>address when a static route is added.
>On NetBSD, the network stack seems to make up a random MAC address and I 
>don't see an ARP who-has request sent. Below, you can see that the MAC 
>address of the gateway ( is correct when the subnet is set 
>to /27:
>watson# arp -a
>? ( at 52:54:00:07:a6:f6 on vioif0
>watson# ifconfig vioif0
>vioif0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
>     address: 52:54:00:24:c2:c3
>     inet netmask 0xffffffe0 broadcast
>     inet6 fe80::5054:ff:fe24:c2c3%vioif0 prefixlen 64 scopeid 0x1
>If I set the subnet and broadcast domain how my ISP wants it, and follow 
> the MAC address is 
>replaced with garbage data:
>watson# ifconfig vioif0 inet netmask 
>watson# route add -host -link -iface vioif0
>add host gateway vioif0
>watson# ping
>PING ( 48 data bytes
>---- PING Statistics----
>3 packets transmitted, 0 packets received, 100.0% packet loss
>watson# arp -a
>? ( at 76:69:6f:69:66:30:00:0e:00:00:00:00 on vioif0 permanent
>Now, if I add the MAC address of the gateway (which isn't a reasonable 
>solution, since my ISP has HRSP and other failovers setup) everything 
>works out:
>watson# route add -host -link -iface vioif0:52540007a6f6
>Does anyone have any idea how to get this configuration to work without 
>the MAC address of the gateway being specified for the route? I feel 
>like this is a bug, as with Linux and FreeBSD this configuration (while 
>I believe it's not particular sane) works just fine, the operating 
>system does an ARP who-has request and you can access the default gateway.
Looks like a bug :-) What is the correct MAC for the gateway?


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