[ovs-discuss] Question about Ethernet over GRE

[Huy Nguyen]

Thanks Justin. I'll take a look at the patch. From the description, this creates a new gre type interface called gretap with the flag ARPHRD_ETHER set instead of ARPHRD_GRE. I assume it will add a fake MAC header in the tunneled  message as well. This should satisfy the bridging requirement. Do you foresee any additional works needed in ovs datapath driver to support this? 
 Huy

--- On Tue, 10/27/09, Justin Pettit <jpettit at nicira.com> wrote:

> From: Justin Pettit <jpettit at nicira.com>
> Subject: Re: [ovs-discuss] Question about Ethernet over GRE
> To: "Huy Nguyen" <huy_nguyen at yahoo.com>
> Cc: discuss at openvswitch.org
> Date: Tuesday, October 27, 2009, 3:19 PM
> Here's the commit that adds Ethernet
> over GRE encapsulation to Linux:
> 
>     http://tinyurl.com/ygpypxw
> 
> Once we have support for the feature, we'll add the
> appropriate  
> documentation about how to configure it through OVS.
> 
> --Justin
> 
> 
> On Oct 27, 2009, at 2:27 PM, Huy Nguyen wrote:
> 
> > What is ethernet over GRE? Is it a different module
> than ip_gre? How  
> > does one create a gre tunnel using this mechanism?
> > Huy
> >
> > --- On Tue, 10/27/09, Justin Pettit <jpettit at nicira.com>
> wrote:
> >
> >> From: Justin Pettit <jpettit at nicira.com>
> >> Subject: Re: [ovs-discuss] Question about Ethernet
> over GRE
> >> To: "Huy Nguyen" <huy_nguyen at yahoo.com>
> >> Cc: discuss at openvswitch.org
> >> Date: Tuesday, October 27, 2009, 1:03 PM
> >> On Oct 27, 2009, at 12:43 PM, Huy
> >> Nguyen wrote:
> >>
> >>> At the openvswitch main page, I saw this
> feature
> >> mentioned as under development. How can I learn
> more about
> >> this feature? Can someone point me to the new code
> or a
> >> functional specs if available?
> >>
> >> We are planning to implement this feature in the
> next
> >> couple of weeks, so all the details have not fully
> been
> >> worked out yet.  The rough plan is that an
> >> administrator will be able to define a virtual
> port that
> >> will define a GRE endpoint and key in the OVS
> configuration
> >> file.  That virtual port can then be added to
> an OVS
> >> bridge over which Ethernet frames will be sent
> and
> >> received.
> >>
> >>> On Linux, packet coming from a gre tunnel
> interface
> >> does not have a real MAC header. I'm curious of
> what is the
> >> plan to be able to bridge gre tunnel interfaces if
> that is
> >> what being developed?
> >>
> >> Support for Ethernet over GRE tunnels was added to
> Linux
> >> 2.6.28.  I haven't had a chance to play with
> them yet,
> >> but I would expect the frames to be able to just
> be sent and
> >> received over the interface that is created when
> the GRE
> >> tunnel is created by OVS.
> >>
> >> --Justin
> >>
> >>
> >>
> >
> >
> >
> 
>