Gratuitous ARP by TimeCapsule?

Hi Guys,

I'm a bit stumped about my Time Capsule's behavior.

There's an AppleTV (2nd gen), a Time capsule and a bunch of other stuff on my LAN.

While troubleshooting another issue, I noticed that the Timecapsule is making gratuitous ARP requests using the AppleTV's IP address.

Frame 9: 60 bytes on wire (480 bits), 60 bytes captured (480 bits) on interface 0 Ethernet II, Src: Apple_c7:48:15 (b8:c7:5d:c7:48:15), Dst: Broadcast (ff:ff:ff:ff:ff:ff)

Address Resolution Protocol (request/gratuitous ARP)

Hardware type: Ethernet (1)

Protocol type: IPv4 (0x0800)

Hardware size: 6

Protocol size: 4

Opcode: request (1)

[Is gratuitous: True]

Sender MAC address: Apple_c7:48:15 (b8:c7:5d:c7:48:15)

Sender IP address: 10.1.18.186

Target MAC address: 00:00:00_00:00:00 (00:00:00:00:00:00)

Target IP address: 10.1.18.186

This is the Time Capsule (sporting IP address 10.1.18.4) spoofing the AppleTV's IP adddress.

This startles the AppleTV, which tries to correct the misunderstanding by announcing itself:

Frame 10: 60 bytes on wire (480 bits), 60 bytes captured (480 bits) on interface 0 Ethernet II, Src: Apple_ac:ff:d7 (9c:20:7b:ac:ff:d7), Dst: Broadcast (ff:ff:ff:ff:ff:ff) Address Resolution Protocol (request) Hardware type: Ethernet (1) Protocol type: IPv4 (0x0800) Hardware size: 6 Protocol size: 4 Opcode: request (1) Sender MAC address: Apple_ac:ff:d7 (9c:20:7b:ac:ff:d7) Sender IP address: 0.0.0.0 Target MAC address: 00:00:00_00:00:00 (00:00:00:00:00:00) Target IP address: 10.1.18.186

Where: It is only the Time machine that sends gratuitous ARPs

Where: It is only the IP of the AppleTV it is ARPing

Can't figure it out why the Timemachine is doing this. Any thoughts?

There's no specific Networking community..as a time machine is an airport extreme with extra twiddly bits..Tried to move it to the airport community, but I'm not authorized..

Thanks,

Leo