Is there a way to find client's mac address on Node.js? I have been searching about it and i found node-sigar project but it didn't works because it throws a "cannot find module ./build/Release/sigar" error.
Unless your code is running on the same LAN segment as the client, you cannot obtain the MAC address of a client. You'd need to likely shell out to a command line tool or native support to gain addresses on the local LAN segment.
For nodejs: https://npmjs.org/search?q=Arp
If you try to get remote clients' MAC addresses, you'll end up with the address of a router more than likely.
The getmac module will do this. It calls out to the command line to get the system's network config info and then uses a regex to parse output to find the mac address. The system commands it uses are getmac (Windows) or ifconfig (other platforms).
来源：https://stackoverflow.com/questions/19647916/getting-clients-mac-address-on-node-js