(I'm not sure what you did differently when you sent this mail, but somehow your mailer botched the "In-Reply-To:" header, which broke the threaded display in Thunderbird. No big deal, but I thought you might want to know.) On 04/22/2013 12:51 PM, james robson wrote:
Date: Thu, 18 Apr 2013 14:14:32 -0400 From: Laine Stump <laine@laine.org> To: libvir-list@redhat.com Subject: Re: [libvirt] [PATCHv2] Configure native vlan modes on Open vSwitch ports Message-ID: <51703808.2000504@laine.org> Content-Type: text/plain; charset=ISO-8859-1
On 04/18/2013 01:44 PM, james robson wrote:
Hello, Has any one been able to review this yet? I realise that the 'Since 1.0.3' in the doc page is now out of date, but is the code itself acceptable? I was hoping that someone with more knowledge of Open vSwitch and/or vlan tagging/trunking/native mode would repond to the message (Kyle?) but there was silence instead...
diff --git a/tests/networkxml2xmlin/openvswitch-net.xml b/tests/networkxml2xmlin/openvswitch-net.xml index a3d82b1..93c49d5 100644 --- a/tests/networkxml2xmlin/openvswitch-net.xml +++ b/tests/networkxml2xmlin/openvswitch-net.xml @@ -21,4 +21,13 @@ <parameters profileid='alice-profile'/> </virtualport> </portgroup> + <portgroup name='tagged'> + <vlan native_mode='tagged' native_tag='123'> + <tag id='555'/> + <tag id='444'/> + </vlan> + <virtualport> + <parameters profileid='tagged-profile'/> + </virtualport> + </portgroup>
As brought up again in a separate conversation today, we prefer to use camelCase rather than underscored in attribute and element names. So, if we were to use the layout you're proposing, the attributes should be called "nativeMode" and "nativeTag".
However, I'm wondering if there might be a better way to structure it. What about this?
<vlan trunk='yes'> <tag id='123' native='tagged|untagged'/> (or whatever values are appropriate)
Sounds like this can be "native='yes'", since there is only the possiblity of a tag being the native tag, or *not* being the native tag.
<tag id='555'/> <tag id='444'/> </vlan>
Do I understand correctly that native mode is telling what to do with packets that come in untagged, and that (using your nomenclature "native_mode='yes' native_tag='123'" means "when an untagged packet come in from this interface, it should be tagged as 123 before forwarding"?
That is correct, setting the native vlan changes how an untagged packet is handled when it enters the port. The difference between the 'tagged' and 'untagged' modes is in how packets on the native vlan are processed before exiting the port.
And what happens when native_mode='yes' but there is no native_tag? In that case you configuration is invalid, and will get an error.
Okay, then doing the config the way I suggest would eliminate that possibility, so it has an upside :-)
(that's what I was trying to describe with <tag id='123' native='untagged'/>, but I don't even know if that makes sense, because I don't know exactly what is the native vlan tag and what is done with it :-) That arrangement would make sense, I chose the arrangement I did for two main reasons. There can only be one native vlan on a port, making it an attribute of the 'vlan' tag enforces this. Also, I wanted to keep the validation and processing separate rather than add 'if native' branches to the loops that operate on the vlan id list. I can see the advantage of having a single setting to configure the native vlan, rather than the two attributes I proposed. If the new suggestion is preferred I can rework my patch to use that format.
I think it's simpler, to do it that way, yes.
Also, is it valid to have a native_mode/native_tag if trunk='no'? (right now trunk is automatically set to 'yes' if there is more than one vlan tag) It isn't valid to have trunk='no' and the native settings. Therefore "<vlan trunk='no' native_mode='tagged' native_tag='123'>" will get an error if you try to enter it. If no "trunk" attribute is set explicitly then it will be set to 'yes'. This means "<vlan native_mode='tagged' native_tag='123'>" is equivalent to "<vlan trunk='yes' native_mode='tagged' native_tag='123'>".
Likewise, if you have more than one <id tag='x'/> element, trunk will automatically be set to yes. So in the end, if you don't foresee any problems with it, I think I do prefer this: <vlan trunk='yes'> <tag id='123' native='yes|no'/> (default is 'no', only one allowed to be yes) <tag id='555'/> <tag id='444'/> </vlan> Note that we'll be going into freeze for 1.0.5 soon, so if you are able to rework the patch within the next couple days, it should go into libvirt-1.0.5 (which *might* end up in Fedora 19?)