Two Network card in one linux system


I've configured two network card in ubuntu 12.10.
I've assigned ipaddress of each interface.

Eth1: address

Eth2: address

Now both interface connected to switch via cable..
Now when i unplugged eth1 cable then eth2 automatically shutdown/ not connected to cable.

But when i'm unplugged cable from eth2 then only eth2 disconnected not Eth1..
SO why eth2 disconnected when i'm unplugged eth1..

Please suggest the solution for the same ASAP

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My assumption is your data was routed on eth0, therefore when you remove eth0, the system has no idea how to route the data.

That being said - you cannot have two default gateways. What is the network for eth0 and Eth1 being used? (data, management...etc) You need to figure out which default gateway to use.
what do you get if you run the command

netstat -rn

or the command

ifconfig -a
you need to look at your gateway setting and add a metric.

look at netstat -rn look for UG
This defines the default gateway.

If you only have one UG entry pointing to eth0 that will explain why when eth0 goes does so does your access to anything other than

usually if eth2 goes down there is no reason for eth1 to go down.
Are you sure you do not have eth0/eth1?
 will wait for response to omarfarid's request for ifconfig -a

use Metric 10 within the interface that you want internet traffic to flow through (preferred)
Metric 20 on the interface that will work when the other is unavailable.

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xeroxzeroxAuthor Commented:
Issue solved by make bonding network
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