Mac OS X: Please explain ifconfig output?

Question

When I do ifconfig on my Mac, I get a list of the following interfaces:

lo0
gif0
stf0
en0
fw0
en1
vmnet8
vmnet1

I wonder what each interface is. Also, which of these is the IP interface ? I don't see eth0 anywhere, which I assume is the standard interface name used by linux systems.

Answer 1

I wonder what each interface is.

• lo0 = loopback
• gif0 = Software Network Interface
• stf0 = 6to4 tunnel interface
• en0 = Ethernet 0
• fw0 = Firewire
• en1 = Ethernet 1
• vmnet8 = Virtual Interface
• vmnet1 = Virtual Interface

Something like that.

Also, which of these is the IP interface ?

There hasn't been "the" IP interface since many years ago. All of them can have IPv4 and/or IPv6 configured and running. The default one to use is defined by the routing table (in particular the default or 0.0.0.0, ::/0 entry).

I don't see eth0 anywhere, which I assume is the standard interface name used by linux systems.

Mac OS X is BSD, not Linux.

Answer 2

Also, on Apple portables en0 is Ethernet and en1 is Airport(WiFi). Mac Pro's will have en3 as well as they have two Ethernet NICs and Airport(WiFi).

vmnet# is usually created by VMs(Parallels/VMWare)