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The host I am working with has two network adapters and is running Ubuntu Server 12.10.

In an attempt to network two computers I used a cross-over cable as in the old 100Mbps days. After doing this I soon realized that you don't use crossover cables for 1000Mbps networks. Reverting back to setting up a simple network with that specific host resulted in very strange behavior. Both network adapters failed to either acquire an IP address via DHCP or be reachable via a static IP assignment.

This seems really crazy that a cross over cable could of broken both adapters? The second adapter was never even plugged into the crossover cable. Is this possible? Networking on the host worked fine before this.

Attempting to restart the host via:

sudo service networking restart

results in an usually long wait time... also ruled out the cable?

Any thoughts?

The etc/network/interfaces file is very simple:

auto lo
iface lo inet loopback

auto eth0
iface eth0 inet dhcp
share|improve this question
DHCP won't work unless there's a DHCP server one one end or the other. With static IPs, make sure they're in the same subnet. Test with ping first and see if you get an ARP reply. – David Schwartz Feb 21 '13 at 4:30
FYI... you CAN use crossover cables 1GbE connections, you just don't need to, most of the time. – SpacemanSpiff Feb 21 '13 at 5:25
@SpacemanSpiff - That is right. Says so here. – ArjunShankar Feb 21 '13 at 8:46
up vote 10 down vote accepted

No, this won't physically damage your network adapters. You're chasing a red herring. There isn't enough detail here to actually solve your real problem, but this is an answer to the question that you're actually asking.

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Could there have been a flag set in the kernel by the cross over cable being plugged in? – Ryan R. Feb 21 '13 at 2:51
No. (more characters.) – mfinni Feb 21 '13 at 2:57
Eth0 was the pci card!!! I couldn't believe it. – Ryan R. Feb 22 '13 at 5:09
+1 for the red herring reference. – BigHomie May 1 '15 at 23:35

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