How to Obtain Mac Address of Remote Computer

# PowerShell
$computername='TESTSERVER'
Get-CimInstance -ClassName Win32_NetworkAdapterConfiguration -Filter "IPEnabled='True'" -ComputerName $computername|Select-Object -Property MACAddress, Description

# Sample output:
MACAddress        Description
----------        -----------
BC:30:5B:XX:XX:XX Intel(R) Ethernet 10G 4P X540/I350 rNDC #2

# Command-line (can also be invoked in PowerShell)
getmac.exe /s COMPUTERNAMEHERE

# Sample output:
PS C:\Windows\system32> getmac.exe /s TESTSERVER01

Physical Address    Transport Name
=================== ==========================================================
BC-30-5B-F8-XX-XX   Media disconnected
BC-30-5B-F8-XX-XX   Media disconnected
BC-30-5B-F8-XX-XX   Media disconnected
BC-30-5B-F8-XX-XX   \Device\Tcpip_{XXXXXXXX-7399-4307-87BA-XXXXXXXX}