Identify Physical Network Interfaces¶
Servers usually have a number of physical network interfaces. The network interfaces names in linux host usually won't tell you much about the which physical network interface corresponds to the interface name. Therefor, it creates a problem when you want to use a specific network interface for a specific purpose but you don't know which physical network interface corresponds to the interface name.
ethtool tool can be used to identify the physical network interface corresponding to a network interface name.
For this method to work, you need a
physical accessto host's network cards and the physical network interfaces should have
Led indicator lights.
This functionality of ethtool may not be supported by all server or network card hardware.
ethtool usually isn't installed by default on a linux host. You can install it by running the following command (debian example):
apt install ethtool
Find the network interfaces present on the host and run the following command for each network interface:
Now you can use the
ethtool command to identify the physical network interface corresponding to the network interface name.
eth0 network interface name:
ethtool --identify eth0
This command will run untill you stop it. When it's running, you should see the LED indicator
light blinking (usually orange) on the physical network interface corresponding to the network interface name.
To get information about the hardware capabilities of the network interface:
ethtool enp12s0f4 Settings for enp12s0f4: Supported ports: [ FIBRE ] Supported link modes: 1000baseT/Full 10000baseT/Full Supported pause frame use: Symmetric Receive-only Supports auto-negotiation: No Supported FEC modes: None Advertised link modes: 10000baseT/Full Advertised pause frame use: Symmetric Advertised auto-negotiation: No Advertised FEC modes: None Link partner advertised link modes: Not reported Link partner advertised pause frame use: Symmetric Link partner advertised auto-negotiation: No Link partner advertised FEC modes: None Speed: 10000Mb/s Duplex: Full Auto-negotiation: off Port: Direct Attach Copper PHYAD: 255 Transceiver: internal Current message level: 0x000000ff (255) drv probe link timer ifdown ifup rx_err tx_err Link detected: yes