I know the IP address of a host on my own LAN. Using that, how can I find its MAC address (without having to physically access it)?
If you are on a Windows machine, open a command box (Start...Run...cmd),
ping the target machine so you have made contact with it, and then issue the command
arp -a to view your local ARP table, which will list IP addresses and their corresponding MAC addresses, e.g.,
C:\Users\L3K> arp -a Interface: 192.168.200.128 --- 0xb Internet Address Physical Address Type 192.168.200.1 00-50-7f-c3-5c-88 dynamic 192.168.200.2 00-50-7f-d1-e1-40 dynamic 192.168.200.6 00-80-77-dd-a8-6b dynamic
If you are on a Linux-based system, install the
arp-scan utility, and then from a command line you can ask for a scan of your network - in my case:
sudo arp-scan 192.168.200.0/24
If you are using an interface other than Ethernet, say, wireless, you will need to specify that, such as
sudo arp-scan -I wlan0 192.168.200.0/24
If you don't know what interface you're using, simply use the appropriate command below.
ifconfig (For Debian based OS such as Ubuntu) ip link (For OS like Arch Linux)
arping comes with the
iputils package on linux. Specify an ip address to ping and it returns the MAC address, even across switches and subnets on the LAN (at least it does on our LAN).
# arping -c 1 -I eth0 10.100.10.11 ARPING 10.100.10.11 from 10.100.10.25 eth0 Unicast reply from 10.100.10.11 [00:22:68:88:F3:90] 0.594ms Sent 1 probes (1 broadcast(s)) Received 1 response(s)
If you have a managed switch or your router lets you view its ARP table you can get this from there.
If the computer you have the IP for is online you can ping it and get its MAC from you local ARP table.
A general note for the sake of others: it is not possible to obtain the MAC address for machines that are on a different LAN since Layer 3 protocols are used for addressing and delivery in this case and MAC is Layer 2.
If both your machine and the target machine are on the same subnet, you can just ping it to cause its IP⟷MAC association to be registered via Address Resolution Protocol (ARP).
ping -c1 $IP arp -n | grep $IP
for example if I want to find the IP of
# ping -c1 10.1.135.150 PING 10.1.135.150 (10.1.135.150) 56(84) bytes of data. 64 bytes from 10.1.135.150: icmp_seq=1 ttl=64 time=1.88 ms --- 10.1.135.150 ping statistics --- 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 1.883/1.883/1.883/0.000 ms
Then query the ARP table
# arp -n | grep 10.1.135.150 10.1.135.150 ether 8c:ae:4c:f4:4d:e1 C eth0
So the MAC of 10.1.135.150 is
You can use utility like http://trogonsoftware.com/trogon-mac-scanner.html or another ip\mac address scanner to scan network for addresses of remote computers on LAN.