Open Stack

On 2/22/2016 5:56 AM, Sean Dague wrote:
> On 02/19/2016 12:49 PM, John Garbutt wrote:
> <snip>
>>
>> Consider a user that uses these four clouds:
>> * nova-network flat DHCP
>> * nova-network VLAN manager
>> * neutron with a single provider network setup
>> * neutron where user needs to create their own network
>>
>> For the first three, the user specifies no network, and they just get
>> a single NIC with some semi-sensible IP address, likely with a gateway
>> to the internet.
>>
>> For the last one, the user ends up with a network with zero NICs. If
>> they then go and configure a network in neutron (and they can now use
>> the new easy one shot give-me-a-network CLI), they start to get VMs
>> just like they would have with nova-network VLAN manager.
>>
>> We all agree the status quo is broken. For me, this is a bug in the
>> API where we need to fix the consistency. Because its a change in the
>> behaviour, it needs to be gated by a micro version.
>>
>> Now, if we step back and created this again, I would agree that
>> --nic=auto is a good idea, so its explicit. However, all our users are
>> used to automatic being the default, all be it a very patchy default.
>> So I think the best evolution here is to fix the inconsistency by
>> making a VM with no network being the explicit option (--no-nic or
>> something?), and failing the build if we are unable to get a nic using
>> an "automatic guess" route. So now the default is more consistent, and
>> those that what a VM with no NIC have a way to get their special case
>> sorted.
>>
>> I think this means I like "option 2" in the summary mail on the ops list.
>
> Thinking through this over the weekend.
>
>  From the API I think I agree with Laski now. An API shouldn't doesn't
> typically need default behavior, it's ok to make folks be explicit. So
> making nic a required parameter is fine.
>
> "nic": "auto"
> "nic": "none"
> "nic": "$name"
>
> nic is now jsonschema enforced, 400 if not provided.
>
> that being said... I think the behavior of CLI tools should default to
> nic auto being implied. The user experience there is different. You use
> cli tools for one off boots of things, so should be as easy as possible.
>
> I think this is one of the places where the UX needs of the API and the
> CLI are definitely different.
>
> 	-Sean
>

Is nic only required when using neutron? Or as part of the microversion 
are we also going to enforce this for nova-network, because if so, that 
seems like a step backward. But if we don't enforce that check for both 
neutron and nova-network, then we have differences in the API again.

-- 

Thanks,

Matt Riedemann