I currently have two servers, One Linux and One Windows.

Each have two NICs.

Their primary NICs would be connected to a Data Center switch with a static IP assigned to them.

Their secondary NICs would be connected to a private un-managed switch on the back-end.

The link light for all four are on, and they report as being connected.

I can get the external IPs to work through their primary NICs, but their secondary NICs cannot communicate with each other.

Pinging would timeout. However, there is one strage occurance. When I ping server 2's private IP (192.168.0.24) with server 1 (192.168.0.20), although it would timeout, the packets on server 2 would increase because of the ping attempt. It's also vice versa, when pinging from Server 2 to server 1, the RX/TX bytes on Server 1 would increase but still would timeout and not reply.

For the Windows server, I just assigned the second NIC a private IP of 192.168.0.24 with a subnet mask of 255.255.255.0 (no gateway/no DNS)

For the linux server, I assigned configured the second NIC this way:

eth1 configuration:

IPADDR=192.168.0.20
NETMASK=255.255.255.0


When I do route -nv, these are the default results with both NIC on:

Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.0.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1
6x.45.6.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth1
0.0.0.0 6x.45.6.1 0.0.0.0 UG 0 0 0 eth0

eth0 represents the 1st NIC with external IP, and works properly.and connects to the net.

eth1 is the secondary NIC connected to the private switch.

Someone suggested my routing tables might be setup wrong and that the NICs are trying to connect to the wrong ones, but this is the default routing table I get after setting up my interfaces.

This is my eth0 configuration:

BOOTPROTO=static
BROADCAST=6x.45.6.255
IPADDR=6x.45.6.xx
NETMASK=255.255.255.0
NETWORK=6x.45.6.0
GATEWAY=6x.45.6.1


There are no active firewalls of any kind.

Could someone please tell me if they have any idea how I can get the secondary NICs to communicate with one another?

Thanks in advance.