[openstack-dev] [Neutron] Use public IP address as instance fixed IP

Kevin Benton blak111 at gmail.com
Mon Aug 25 06:07:56 UTC 2014


I think this will depend on the deployment type for the L3 agent. If the
gateway_external_network_id is left blank for the L3 agent, the external
network is vlan tagged just like any regular network and doesn't have an
independent bridge.[1] In that deployment scenario it should work fine.


On Sun, Aug 24, 2014 at 9:30 AM, Mohammad Banikazemi <mb at us.ibm.com> wrote:

>  Would this work? We used to have warnings in Neutron docs indicating
> that instances should not be attached to external networks:
> "It is important to understand that you should not attach the instance to
> Ext-Net directly. Instead, you must use a floating IP to make it accessible
> from the external network."
>
> In this particular case and with the OVS plugin, the traffic on the
> external network which now hosts tenant VMs (on OpenStack compute nodes)
> should get routed from the br-int to the external bridge br-ex using for
> example the appropriate vlan id (what if external network does not use
> vlan?) and then to the external network without doing the NATing. Would
> this traffic go through the veth pair connecting the br-int and br-ex?
>
> Mohammad
>
> [image: Inactive hide details for Kevin Benton ---08/23/2014 01:37:28
> AM---Yes, you should be able to create a shared/external network]Kevin
> Benton ---08/23/2014 01:37:28 AM---Yes, you should be able to create a
> shared/external network within Neutron to accomplish this.
>
> From: Kevin Benton <blak111 at gmail.com>
> To: "OpenStack Development Mailing List (not for usage questions)" <
> openstack-dev at lists.openstack.org>
> Date: 08/23/2014 01:37 AM
> Subject: Re: [openstack-dev] [Neutron] Use public IP address as instance
> fixed IP
> ------------------------------
>
>
>
> Yes, you should be able to create a shared/external network within Neutron
> to accomplish this.
>
>
> On Fri, Aug 22, 2014 at 7:25 AM, Bao Wang <*bywang98 at gmail.com*
> <bywang98 at gmail.com>> wrote:
>
>    Thank you for your response. Could this be done naturally with
>    Openstack neutron or have to be done manually outside neutron ?  As we are
>    expecting to orchestrate hundreds of NFV with all similar network
>    configuration, programmability is another key element.
>
>
>    On Thu, Aug 21, 2014 at 3:52 PM, Kevin Benton <*blak111 at gmail.com*
>    <blak111 at gmail.com>> wrote:
>       Have you tried making the external network shared as well?
>       Instances that need a private IP with NAT attach to an internal network and
>       go through the router like normal. Instances that need a public IP without
>       NAT would just attach directly to the external network.
>
>
>       On Thu, Aug 21, 2014 at 7:06 AM, Bao Wang <*bywang98 at gmail.com*
>       <bywang98 at gmail.com>> wrote:
>          I have a very complex Openstack deployment for NFV. It could not
>          be deployed as Flat. It will have a lot of isolated private networks. Some
>          interfaces of a group VM instances will need bridged network with their
>          fixed IP addresses to communicate with outside world while other interfaces
>          from the same set of VM should keep isolated with real private/fixed IP
>          addresses. What happen if we use public IP addresses directly as fixed IP
>          on those interfaces ? Will this work with Openstack neutron networking ?
>          Will Openstack do NAT automatically on those ?
>
>          Overall, the requirement is to use the fixed/public IP to
>          communicate with outside directly on some interfaces of some VM instances
>          while keeping others as private. The floating IP is not an option here
>
>          _______________________________________________
>          OpenStack-dev mailing list
> *OpenStack-dev at lists.openstack.org* <OpenStack-dev at lists.openstack.org>
> *http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev*
>          <http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev>
>
>
>
>       --
>       Kevin Benton
>
>       _______________________________________________
>       OpenStack-dev mailing list
> *OpenStack-dev at lists.openstack.org* <OpenStack-dev at lists.openstack.org>
> *http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev*
>       <http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev>
>
>
>    _______________________________________________
>    OpenStack-dev mailing list
> *OpenStack-dev at lists.openstack.org* <OpenStack-dev at lists.openstack.org>
> *http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev*
>    <http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev>
>
>
>
>
> --
> Kevin Benton_______________________________________________
> OpenStack-dev mailing list
> OpenStack-dev at lists.openstack.org
> http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
>
>
> _______________________________________________
> OpenStack-dev mailing list
> OpenStack-dev at lists.openstack.org
> http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
>
>


-- 
Kevin Benton
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstack.org/pipermail/openstack-dev/attachments/20140824/a3e1d404/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: graycol.gif
Type: image/gif
Size: 105 bytes
Desc: not available
URL: <http://lists.openstack.org/pipermail/openstack-dev/attachments/20140824/a3e1d404/attachment.gif>


More information about the OpenStack-dev mailing list