network issue with multiple NICs


New Member
Feb 14, 2013

I've installed Proxmox VE 2.2 on a Dell R420 server. The server has 2 network cards, the embedded dual port 1Gb (eth0, eth1) and a Dual port Intel 10Gb card (eth2, eth3). I have 2 networks, one public network (41.1.1.x, netmask for management, etc. and a private network for storage traffic (192.168.10.x, netmask The public network connects to 1 1Gb port (eth0) and the private network connects to 1 10Gb port (eth2). On proxmox I can configure both ethernet interfaces (eth0 & eth2) to work on their respective networks. From the console I can ping machines on both networks fine.

I then set up a KVM VM (CentOS 6.3) and configure 2 vistual network adaptors. vmbr0 (eth0) and vmbr1 (eth2). On the VM I set up net0 bridged to vmbr0 and net1 bridged to vmbr1.

Here is my /etc/network/interfaces file (proxmox):
# network interface settings
auto lo
iface lo inet loopback

iface eth0 inet manual

iface eth1 inet manual

iface eth2 inet manual

iface eth3 inet manual

auto vmbr0
iface vmbr0 inet static
bridge_ports eth0
bridge_stp off
bridge_fd 0

auto vmbr1
iface vmbr1 inet static
bridge_ports eth2
bridge_stp off
bridge_fd 0

My issue is that from within the VM I can only ping the public network 41.1.1.x and not the private network 192.168.10.x. What am I doing wrong?




New Member
Nov 28, 2006
You're probably going to want to SSH in and do "dmesg | grep eth" and confirm that the NIC mac addresses and names match up as you are wanting them to be. If it doesn't then you'll need to change the IP addresses around to match the NIC naming. I've found that in multi-NIC systems the eth names thend to change from what you are expecting.


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