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On 2019/12/5 01:05, Stefano Garzarella wrote:
> On Wed, Dec 04, 2019 at 03:54:06PM +0000, Montes, Julio wrote:
>> Hi Stefano
> 
> Hi Julio
> 
>>
>>> - Host: assign the same CID of VMs running in different network
>>>   namespaces
>>
>> this means two VMs running in different namespace can use the same CID?
> 
> Exactly.
> 
>> currently we use VHOST_VSOCK_SET_GUEST_CID to get a unique context ID, is this going to change?
> 
> The only change is that the CID is unique in the network namespace
> domain.
> 
>>
>>> 1. Is the VMM (e.g. QEMU) running in a network namespace?
>>
>> yes, see https://github.com/kata-containers/runtime/blob/62cd08044d78912228d9dc800cb1b8bd3de3b971/virtcontainers/sandbox.go#L1024-L1041
>>
>>> 2. Is the host application, that use vsock to communicate with the
>>>    guest, running in the same network namespace?
>>
>> afaik, no
> 
> This could be a problem with the RFC that I sent, because we allow only
> the processes in the same netns of the VMM, to communicate with the
> guest.
> 
> Do you think could be an easy change in the Kata runtime?
> I need to look better, but if you already know the answer you'll
> save me some time :)
Hi Stefano,

While I understand the motivation of the change, do users have an option 
to opt out of the namespaced vsock communication? I'm considering a 
possible scenario that someone uses a single host daemon to manage all 
the guests like we did in the hyperd project. Then there is no way for 
such a daemon to communicate with guests with namespaced vsock.

Cheers,
Tao

> 
>>
>>> 3. Is the agent in the guest running outside a netns (default init_netns)?
>>
>> yes
> 
> This is nice.
> 
> Thank you very much,
> Stefano
> 
> 
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