Sign up ×
Server Fault is a question and answer site for system and network administrators. It's 100% free, no registration required.

I have two servers with Ganeti installed (Xen) I want to be able to migrate the instance between the two servers so the instance's network configuration needs to be host agnostic. The datacenter that hosts the two servers supplied me with a failover IP subnet (/28) that I can script to switch between the two hosts, but it does mean that all of my /28 IPs are pointing at one server at a time. I had a second NIC installed in each server so that I can use drbd I would also like to use this eth1 to pass external traffic from the host that currently has the subnet assigned and the secondary host. I would also like to add iptables to avoid a rouge instance attempting to bind to an IP not assigned to it and, although I am unsure if it is possible, for the outbound traffic to go out via the local eth0 even when the request came in via the other server on eth1, I am unsure if this is at all possible. Does anyone have experience with this sort of configuration or know of a resource online where I can find this info?

Thanks in advance,


share|improve this question
I am sure you could get clever with bridges here, but it would be much easier just to put a switch, even if it's a cheap one, in front of the servers. What you're talking about here is basic clustering. –  SpacemanSpiff Jan 27 '13 at 17:42
@SpacemanSpiff thanks for the fast reply, would a switch between them not create a single point of failure? I want to avoid this and feel that the "get clever with bridges" option is what I am after. –  iainmackay85 Jan 27 '13 at 21:02

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Browse other questions tagged or ask your own question.