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I have the following in my /etc/network/interfaces file

auto lo
iface lo inet loopback

auto eth0
iface eth0 inet static

auto eth1
iface eth1 inet static

On reboot the server is not configuring both interfaces then I did a ifconfig and noticed that both eth0 and eth1 have the same MAC address. So it seems like both interfaces are being assigned to the same NIC. I have 2 Nics in the server. Can anyone help me whats going on

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Are you certain they both have the exact same mac address? Many interfaces built into servers are only different by a single bit. – Zoredache Dec 5 '12 at 22:26
What is the output of ifconfig ? – gparent Dec 5 '12 at 23:03

Find out other NIC MAC address and place it in /etc/network/interfaces

In CentOS I could determine information about network devices in:


I think hwinfo command might help too.

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How do you place the MAC address in the interfaces file? – Cesar Bielich Dec 5 '12 at 22:24
e.g. under gateway add hwaddress ether 01:02:03:04:05:06 – Zim3r Dec 5 '12 at 22:29
If you just delete or rename the above file, it will get regenerated after reboot. – SpacemanSpiff Dec 6 '12 at 0:59

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