[Openstack] Devstack multinode Installation network configuration help and bridging explanation

Vishvananda Ishaya vishvananda at gmail.com
Wed Aug 15 19:13:05 UTC 2012


On Aug 14, 2012, at 10:52 PM, Kurt Scholtens <burnbrighter at hotmail.com> wrote:

> Vish - 
> 
> Thank you for responding.  So, when using multiple interfaces, will setting the PUBLIC_INTERFACE to the separate interface w/o VLANing work?  Is that what you are saying below?  Are any additional configuration parameters then required such as "flat_network _bridge"?

It should work on two separate interfaces with just that change.

> 
> Something still puzzling me:
> From my routing table below, it appears both the public interface AND the flat interface are on br100 (which is bound to eth2).  I didn't think a bridge could have more than one subnet attached to it at any one time. I was apparently wrong.
multiple unrelated ips on an interface is fine
> My br100 has an associated address of 11.0.4.12, but eth2 has the IP address of 192.168.12.105br100 then, has the public_interface traffic (floating_range - 192.168.12.x) and the fixed_address traffic traversing eth2, correct?     Is my understanding of what is going on correct?

if the interface specified in flat_interface has an ip on it, it moves it to the bridge. So you will often have multiple ips on the bridge: 1) the hosts original ip 2) an ip in the fixed_range for dnsmasq 3) all floating ips (assuming public_interface=br100) In addition, all guest vnics are on the same bridge.

public_interface just controls which interface is used for the floating ips. If you want them to be usable from outside the host, you have to make sure that is an interface (ir a bridge on an interface) that your router knows about.

Vish
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstack.org/pipermail/openstack/attachments/20120815/4284fcbc/attachment.html>


More information about the Openstack mailing list