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[Kurt Scholtens <burnbrighter@xxxxxxxxxxx>]

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"?

Something still puzzling me:
1. 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.
2. My br100 has an associated address of 11.0.4.12, but eth2 has the IP
address of 192.168.12.105.
br100 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?

convirt@convirt-r01:~/devstack$ netstat -rn
Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS Window  irtt
Iface
0.0.0.0         192.168.12.1    0.0.0.0         UG        0 0          0
br100
10.0.4.0        0.0.0.0         255.255.255.0   U         0 0          0
eth0
10.0.5.0        0.0.0.0         255.255.255.0   U         0 0          0
eth1
11.0.4.0        0.0.0.0         255.255.255.0   U         0 0          0
br100
192.168.12.0    0.0.0.0         255.255.255.0   U         0 0          0
br100
192.168.122.0   0.0.0.0         255.255.255.0   U         0 0          0
virbr0

convirt@convirt-r01:~/devstack$ brctl show
bridge name bridge id STP enabled interfaces
br100 8000.00163e098238 no eth2
vnet0
virbr0 8000.000000000000 yes

Thanks for taking the time to explain things,
~kvs

From:  Vishvananda Ishaya <vishvananda@xxxxxxxxx>
Date:  Tuesday, August 14, 2012 8:01 PM
To:  Kurt Scholtens <burnbrighter@xxxxxxxxxxx>
Cc:  <openstack@xxxxxxxxxxxxxxxxxxx>
Subject:  Re: [Openstack] Devstack multinode Installation network
configuration help and bridging explanation


On Aug 14, 2012, at 1:24 PM, Kurt Scholtens <burnbrighter@xxxxxxxxxxx>
wrote:

> Any takers?
> 
> I am looking for guidance on my current deployment.   Let me start by saying,
> it works.  That being said, I want to ensure what I am doing makes sense
> because I'm slightly confused by the networking.  Specifically, the bridging
> doesn't make sense at all.  If you look at my bridging below, it appears both
> my public network (192.168.12.x) and my host to host management network
> (10.0.5.x) are getting bridged on br100.  More precisely it appears my
> FIXED_NETWORK (11.0.4.x) as well as my public network aka FLOATING_RANGE are
> getting bridged to  br100.  I do access my openstack hosts on 192.168.12.x as
> well as my openstack instances on this network.  I just am not understanding
> the networking for this set up, even though it works.

If you want the floating ips on a different interface (say eth1) you can
use:

PUBLIC_INTERFACE=eth1

devstack defaults PUBLIC_INTERFACE to br100 because that is the only way to
make it work if you have a single interface and you don't set up vlans. with
multiple interfaces and vlans, generally you put public_interface and
flat_interface on different devices.

Vish