openstack team mailing list archive

[Dan Wendlandt <dan@xxxxxxxxxx>]

Hi Janis,


On Thu, Sep 27, 2012 at 3:20 PM, Jānis Ģeņģeris
<janis.gengeris@xxxxxxxxx> wrote:
> Hello,
>
> What are the limitations that can be done with quantum related to NIC
> configuration for individual VMs?
>
> For example, is it possible to have multiple floating IPs and multiple fixed
> IPs assigned to the same
> VM (the IPs might come from the same and/or different subnets)?

The spec for all core APIs is complete and available here:
http://docs.openstack.org/api/openstack-network/2.0/content/index.html
.  Quantum ports have a list of fixed_ips
(http://docs.openstack.org/api/openstack-network/2.0/content/Show_port.html),
meaning that multiple IPs are supported.

The floating IP stuff is actually an extension, not part of the core
API for folsom.  We're still adding content for extensions to the
guide (I think its under review right now... should be available early
next week).  Right now the code actually limits each port to having a
single floating IP, but in reality, the you should probably be able to
have a different floating IP for each fixed_ip on the port, and in
fact, a different floating-ip from each external network for each
fixed IP on the port (having multiple floating-IPs from the same
external network for a single fixed IP would lead to ambiguity when
SNATing connections).  I've filed this bug to track the appropriate
code changes: https://bugs.launchpad.net/quantum/+bug/1057844 .  The
change is very simple, and so should be easy to pull into a
stable/folsom release.


> How much
> does it depend on the chosen hypervisor?

None of the Quantum logic depends on the hypervisor.  What really
matters is the method for how you choose to inject IP addresses into
the VM.  The main methods I'm aware of are filesystem injection by
nova, DHCP injection, or using some type of agent.  Filesystem
injection in particular may be hypervisor-specific.

>
> Quantum documentation is quite recent and is still full of 'TBD', but in the
> current version there is nothing about
> the features/limitations Quantum brings to the individual VM instance
> network configuration in comparison to legacy
> nova-network.

Most of the TBD's were filled in by some commits that landed
yesterday, but given the large amount of new functionality in Quantum
during Folsom, there will definitely be some doc gaps that we need
users to help us identify.  I'd encourage you to file doc bugs here
(https://bugs.launchpad.net/openstack-manuals) to make sure these gaps
are brought to the attention of our great docs team.

Dan

>
> Regards,
> --janis
>
> _______________________________________________
> Mailing list: https://launchpad.net/~openstack
> Post to     : openstack@xxxxxxxxxxxxxxxxxxx
> Unsubscribe : https://launchpad.net/~openstack
> More help   : https://help.launchpad.net/ListHelp
>



-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~
Dan Wendlandt
Nicira, Inc: www.nicira.com
twitter: danwendlandt
~~~~~~~~~~~~~~~~~~~~~~~~~~~