Resolving a MAC address to an IP or system

[Swanky]

I have a syslog full of errors generated by bootp. They say a certain MAC address has a bad address. It adds an error every few seconds.

Is there a way to resolve where this MAC address is? It is a 52.41.53.x.x so I have found it's a RAS. I just don't know what's doing it. Every utility I look at is for IP addresses and 'arp -a' does not show it.

Can a device have a MAC address and not an IP address, like a hub, and do this?

I have disabled bootp for now, but I would like a better solution.

http://www.live365.com/cgi-bin/directory.cgi?autostart=swanky

 

[pcunix]

A device that doesn't have an ip address uses bootp to GET an address, so it's asking your server to provide one.

You can configure bootp to give it one or perhaps even just do

arp -s giveitaname 00:c0: etc

(giveitaname would have to be in /etc/hosts)

You could then try telneting to it..

One other hint to may not know: the first part of a mac address uniquely identifies the manufactuer.

http://www.cavebear.com/CaveBear/Ethernet/vendor.html

has a nice list of vendor id's- knowing who made the device might help you locate it.





Tony Lawrence
SCO Unix/Linux Resources

http://pcunix.com

tony@pcunix.com

 

[stanhubble]

A device can have a MAC address and not be running TCP so therefore it would not have an IP address.

I found some discussion (although dated) on DHCP and RAS.

http://www.isc.org/ml-archives/dhcp-server/1999/12/msg00191.html

http://www.isc.org/ml-archives/dhcp-server/1999/12/msg00193.html

stan hubble