tech-net archive

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]

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


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
    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 broadcast
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.

Thank you,


Attachment: smime.p7s
Description: S/MIME Cryptographic Signature

Home | Main Index | Thread Index | Old Index