[ovs-discuss] GRE over IPv6 configuration

[Gregory Rose]

On 6/14/2019 10:55 AM, Ben Pfaff wrote:
> On Wed, Jun 05, 2019 at 09:30:18AM -0700, Gregory Rose wrote:
>> On 6/4/2019 11:38 AM, Ben Pfaff wrote:
>>> On Tue, Jun 04, 2019 at 06:08:00PM +0000, Eli Britstein wrote:
>>>> On 6/4/2019 8:24 PM, Ben Pfaff wrote:
>>>>> On Tue, Jun 04, 2019 at 03:13:02PM +0000, Eli Britstein wrote:
>>>>>> Hello,
>>>>>>
>>>>>> I would like to configure a GRE tunnel over IPv6, on a Linux system.
>>>>>> However, I encounter the following:
>>>>>>
>>>>>> My command:
>>>>>> ovs-vsctl add-port br1 gre6 -- set interface gre6 type=ip6gre
>>>>>> options:remote_ip= 2001:db8:0:f102::11 options:key=55
>>>>>>
>>>>>> Output:
>>>>>> ovs-vsctl: Error detected while setting up 'gre6': could not add network
>>>>>> device gre6 to ofproto (Address family not supported by protocol).  See
>>>>>> ovs-vswitchd log for details.
>>>>>> ovs-vsctl: The default log directory is "/var/log/openvswitch".
>>>>>>
>>>>>> In the log:
>>>>>> bridge|WARN|could not add network device gre6 to ofproto (Address family
>>>>>> not supported by protocol)
>>>>>>
>>>>>> I notice that if I want to define a ip6gretap with “ip link”, there is a
>>>>>> need to use “-6” option, to set the correct family.
>>>>>>
>>>>>> Is there a way to note the correct family (though I think should be
>>>>>> implicit by “ip6gre”)? Or maybe some other configuration?
>>>>> OVS doesn't have an "ip6gre" interface type.  Just use "gre".
>>>> I see it does in lib/netdev-vport.c, line 1222. Isn't that ip6gre?
>>> Um, that's weird.  We don't document it.  I thought for sure that we
>>> tried to make our "regular" tunnels just accept both IPv4 and IPv6
>>> addresses.
>> Hmm, no documentation.  Uh, that's not good.  I'll check that.
> Did you get a chance to take a look?  It would be good to improve the
> documentation.

My apologies but no, not yet.  I have this task flagged and will get to 
it sooner rather than later.

Meanwhile, there seems to be a gap between out of tree OVS capabilities 
with ip6gre and what is upstream.  I can
document what our out of tree kernel drivers can do but will need to 
investigate further for what is going on with the
upstream ip6 gre.

Thanks,

- Greg