Networking Q concerning /etc/network/interfaces

Running wheezy - 3.0.0-1-686-pae

I'm getting confused by what I see in /etc/network/interfaces,
compared to what I see with ifconfig -a.

What I see in /etc/network/interfaces:

auto lo
iface lo inet loopback
allow-hotplug eth0
iface eth0 inet dhcp

Does not match what I see with ifconfig -a

eth0 Link encap:Ethernet HWaddr 00:40:f4:b5:29:41
inet addr:192.168.1.54 Bcast:192.168.1.255 Mask:255.255.255.0
BROADCAST MULTICAST MTU:1500 Metric:1


[...]

eth1 Link encap:Ethernet HWaddr 00:11:09:ee:6c:04
inet addr:192.168.1.42 Bcast:192.168.1.255 Mask:255.255.255.0
inet6 addr: fe80::211:9ff:feee:6c04/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1

[...]

------- --------- ---=--- --------- --------

What shows as eth1 in ifconfig is the working IP (...42) of this host.
Nothing is plugged into device seen as eth0 (...54). That is,
although there is a second network adapter, nothing is plugged into
it, and all traffic comes and goes on [...]42.

It can be seen in the output of netstat -r

Kernel IP routing table
Destination Gateway Genmask Flags MSS Window irtt Iface
default fw.local.lan 0.0.0.0 UG 0 0 0 eth1
192.168.1.0 * 255.255.255.0 U 0 0 0 eth1


So it appears at a superficial reckoning that dhcp has assigned an
address to eth0, but that address appears to be attached to eth1 in
ifconfig and netstat output.

What explains this apparent anomaly?


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