How to find MAC addresses on network?

[Thomas Kaiser]

Chris G wrote:
> On Fri, Jan 23, 2009 at 06:44:40PM +0100, Thomas Kaiser wrote:
>> Chris G wrote:
>>> On Thu, Jan 22, 2009 at 11:04:44PM +0100, Thomas Kaiser wrote:
>>>> Chris G wrote:
>>>>> Is there a (reasonably) straightforward way of finding the MAC
>>>>> addresses of systems (well, strictly, interfaces) on a network?
>>>>>
>>>>> arping works for some but not all of my hardware, presumably some
>>>>> things (like my HP printer) don't respond to arping.  What can I use
>>>>> to find the MAC address of the printer?
>>>>>
>>>> Connect to your device somehow (http, print a document) and after run 
>>>> "arp" in a terminal. The MAC addresses of the devices you connected 
>>>> stays in the ARP cache of your computer for some time. "arp" just shows 
>>>> the cache.
>>>>
>>> Thanks, works for just about everything except the HP printer, that
>>> returns:- 
>>>
>>>     hp7310                           (incomplete)                     eth0
>>>
>>>
>> So, that means there is now MAC address in the cache. And that means you 
>> could not connect to the printer!
>>
>> Can you print with this printer?
>>
> Yes, when I connect it!  I found the plug had fallen out - oops!  :-)
> 
> However, even when it's working correctly, the printer doesn't give
> its hostname when it gets its IP address via DHCP.  Everything else on
> the network gives a name but this HP printer doesn't.
> 

Hostname? I thought you would like to get the MAC address?
After you printed something to the printer you should see the MAC 
address with "arp -vn".

Thomas