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I'm not sure if these have a name, but on most computers I use the interface prefixes are usually:

  • eth- : Ethernet/Wired
  • wlan- : Wireless/WiFi

However, on my ASUS RT-N56U, I have the following:

  • br0 : 'Ethernet' - Bridge?
  • eth2 : 'Ethernet', IPv6 (where are 0 and 1?)
  • eth3 : 'Ethernet', IPv4 (the one with my WAN IP)
  • lo : 'Local Loopback' - What's this for?
  • ra0 : 'Ethernet' - ?
  • rai0 : 'Ethernet' - ?

Are there others? What do they mean?

jlliagre
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Ehryk
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3 Answers3

10

From the ASUS RT-N56U wiki page:

What are the existing network interfaces (transcript naming interfaces)?

    br0 = LAN + WLAN + AP-Client + WDS
    eth2 = Ethernet interface GMAC1, that connected to the switch (trunk port).
    eth2.1 = LAN (VLAN VID1)
    eth2.2 = WAN (VLAN VID2)
    ra0 = WLAN 5GHz
    ra1 = WLAN 5GHz Guest
    rai0 = WLAN 2.4GHz
    rai1 = WLAN 2.4GHz Guest
    apcli0 = AP-Client 5GHz
    apclii0 = AP-Client 2.4GHz
    wds0-wds3 = WDS 5GHz
    wdsi0-wdsi3 = WDS 2.4GHz 

In the no-VLAN firmware

    eth2 = LAN
    eth3 = WAN
matt wilkie
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don_crissti
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    Thanks for the list, I was really hoping there was some 'standard', but in lieu of one, this explains my particular case. – Ehryk Jun 25 '13 at 20:54
6

They mean whatever the driver designer wanted them to mean. There are many many others too, like ib0 for Infiband devices. But I am not aware of anywhere that has a complete list as again it depends on who develops the driver as to what the name of the device is. Usually it gives some clue as to the type of board but that is about it. The number after the device designation is generally used to indicate which of several ports/devices the device is.

mdpc
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  • Any insight into br, lo, ra and rai? – Ehryk Jun 25 '13 at 04:37
  • have you googled around? You might find the answer. lo is the loopback driver (handler for 127.0.0.1 ethernet address). – mdpc Jun 25 '13 at 04:38
  • Confirm that `lo` is loopback (connecting to your own computer doesn't require a real Ethernet interface, so the kernel has a special fake interface for this) and `br` is bridge (you create one with [`brctl`](http://bwachter.lart.info/linux/bridges.html)). – tripleee Jun 25 '13 at 04:49
  • I've seen both `wlan` and `wifi` for wireless. On Ubuntu the bare interface comes up as `wlan0` but MDNS and what not creates some wrappers and you see the virtual interface `wifi0` instead. – tripleee Jun 25 '13 at 04:52
  • Some hardware gets a specific `ethX` number by `udev` rules. You might have rules in place which assign your `eth3` and `eth4` cards so that you know which is which (different speed, different hardware, different drivers, whatever). – tripleee Jun 25 '13 at 04:53
3

You can see all interfaces using ifconfig -a or ip address show; It will show them even they are down.

Mohammad Etemaddar
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    On my particular machine, yes. That's not what I'm interested in - I'm asking what the prefixes mean across all machines, I.E. eth- usually means ethernet, wlan- or wifi- usually mean wireless, and I'm asking what the rest are. – Ehryk Jun 25 '13 at 20:51