[ubuntu] Setting Multiple NIC with same gateway in one Machine

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http://ubuntuforums.org – hi guys, a newbie network administrator here... i have a PC, I want to use it as transparent proxy server and also running one virtual machine as MySQL server, I'm using 3 network cards, eth0 is used to connect the server to my router (WAN) (IP eth1 is used as gateway to share internet connection to my network (IP and last can i use eth2 ( as bridged NIC to my virtual machine, so the eth2 will have the same gateway as eth1.. before I set the eth2, the proxy was working fine, i can connect to internet using client computer. but when i try set up eth2 at (Hardware)