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I have an Ubuntu Server I'm adding some interfaces for and I can't figure out what I am be missing.

Here's my /etc/network/interfaces/

auto lo
iface lo inet loopback

# The primary network interface
auto eth0
iface eth0 inet static

 iface eth0:0 inet static

Then the following occurs:

sudo ifup eth0:0
RTNETLINK answers: File exists
Failed to bring up eth0:0.

Looked around for this issue and everyone seems to encounter it in different ways. Any ideas? Thanks!

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up vote 2 down vote accepted

The gateway stanza creates a default route for the whole machine. The second stanza would create a second default route, and you get a File exists error.

This error means you'd have a second route for the prefix -- that's what a default route is.

If you need further explanations about routing, please fell free to ask.

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Thanks, I got it working and this also helps. :) – Bartek Apr 25 '12 at 13:24
@Luis Bruno Hi, can you help me out with this… – wolfgang Sep 22 '15 at 15:50

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