Re: Determine IP Adrress from MAC Address

[Joe Pfeiffer <pfeiffer@cs.nmsu.edu>]

Muntasim-Ul-Haque <tranjeeshan@inventati.org> writes:

> Hi,
> How can I determine the IP address if I already have the MAC address
> or Hardware Address? What is the most convenient way?
>
> -Muntasim Ul Haque

The fact that you already have the MAC address doesn't matter in finding
out your IP address.

ifconfig will give you both the MAC address and IP address of all your
network interfaces:

snowball:593$ ifconfig
eth0      Link encap:Ethernet  HWaddr d4:3d:7e:01:8c:8f  
          inet addr:192.168.13.2  Bcast:192.168.13.255  Mask:255.255.255.0
          inet6 addr: fe80::d63d:7eff:fe01:8c8f/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:75979320 errors:0 dropped:0 overruns:0 frame:0
          TX packets:79860948 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:26691502625 (24.8 GiB)  TX bytes:34703381554 (32.3 GiB)

lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:65536  Metric:1
          RX packets:590910 errors:0 dropped:0 overruns:0 frame:0
          TX packets:590910 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:38390044 (36.6 MiB)  TX bytes:38390044 (36.6 MiB)

So eth0 (my ethernet card) has IP address 192.168.13.2, and lo (the
loopback "device", used for programs on my machine to talk to other
programs on the same machine) has 127.0.0.1 -- it's actually always
127.0.0.1

If you have network devices that aren't configured at the moment,
ifconfig -a will tell you about them too (but they won't have IP
addresses).