Xen devel - Dec 2011 - Re: [help] what's the relationship between vif*.*

thanks, you mean that only the tap device  is enough for HVM domainU and the vif
is specially for paravirtulization.
  
 On 26.12.2011 04:30, ???aware wrote:
> >Hi everyone,
>>  A pair of network interface, vif and tap, will connect the bridge
> >when a vm starts. What's their relationship?
> > thanks for reply~
>>
>> cheers
>> bruce
>If I understand correctly, the vif is a virtual interface that works 
>with pv drivers in domU.  The tap is a Qemu interface that is used with 
>HVMs that don't have pv drivers.  So, if you start a HVM domU,
you'll
>have the vif that Xen creates and the tap that Qemu creates, if pv 
>drivers are available, then once they are loaded Domu uses them and the 
>tap goes away, but if not then both remain, but only the tap interface 
>is being used.  Obviously, if you need more detailed explaination, then 
>I'm of no further use.:)
>Mike
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xensource.com
http://lists.xensource.com/xen-devel

2011/12/27 ¤終於aware <250716708@qq.com>:
> thanks, you mean that only the tap device  is enough for HVM domainU and
the
Yes, sort of.
> vif is specially for paravirtulization.
Yes, as in PV drivers, not in PV vs HVM domU.

As Mike said, HVM domU can also use PV drivers. Example: newer linux
distros (which uses xen-netfront module), or windows with PV drivers
(e.g. with GPLPV). In this case HVM domU also uses vif, and the tap
device will be unused (and in some cases, removed).

-- 
Fajar

_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xensource.com
http://lists.xensource.com/xen-devel