Proxy ARP

[tedauction]

Hello, my example switch has no default gateway or routing table, but it does have multiple VLANs and ports associated with these.

My question is if it wants to make an ARP request, which interface does it send this out on ? - or does it just flood the ARP request out all interfaces.

n.b. in this example situation the connected router will be operating Proxy ARP.

Thanks kindly,

[S-Lemming]

The switch itself would only send an ARP request if it needs to send traffic to a device in its own subnet. Since the ARP is a broadcast it would be sent on all ports belonging to the same VLAN as the IP address from where it would be sent, which would be the management IP address.

For a device connected to the switch which sends an ARP request, the switch will send it on all ports belongning to the VLAN which the originating device is connected on.

Hope this helps.