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I am in a network that determines by the MAC address of attached devices to which VLAN the used switch port has to be set to.

For regular devices that use DHCP the MAC address can be simply determined as the devices itself send packets when they recognize a link-up event. However I am interested in how this mechanism is designed to work for devices that use a static IP configuration and that do not broadcast any further packets initially/regularily.

If the device does not send anything the VLAN system can not be configured because the MAC address is unknown.

Is there any standard/RFC dealing with this situation. Is there something like a "hello" packet the device has to respond, exposing it's MAC address?

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If the device is using static IP, then you can get its MAC address from the ARP table (do this on computer in the same local network):

  1. Make sure device's MAC address is discovered via ARP: ping <ipaddress>
  2. Get the device's MAC address: arp -a <ipaddress>
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Nice try but how should the VLAN system know the IP address of the attached device? – Robert Dec 21 '11 at 8:18
@Robert: Please define "VLAN system". Also, ARP replies are exposing MAC addresses as well as DHCP, so maybe you need to define your problem better? – haimg Dec 21 '11 at 17:27
AFAIK it's some Cisco system managing VLANs. But your are pointing out the crucial part: the MAC is contained in [ARP] responses - but without request no response. And that was my question: Is there a standard for requests for obtaining the MAC address in a VLAN system? – Robert Dec 22 '11 at 11:40

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