[ovs-dev] OFPMT_TABLE_FEATURES is supported in OVS or not

[tech_kals Kals]

Hi Ben,

Let me rephrase my question. I know, how flow entries are added into a
single flow table. But, I have few doubts while installing a flow entry
into multiple flow tables.

1) Switch can maintain any number of flow tables. But, the controller will
come to know about it only through "OFPMT_TABLE_FEATURES". If the switch
doesnt send switch capability to the controller through "OFPMT_TABLE_FEATURES"
then controller will think that there is a single flow table in the switch.
OVS currently doesnt support "OFPMT_TABLE_FEATURES", so the controller may
not aware that OVS has multiple flow tables. Am I rght ?


2) If controller doesn't know about multiple flow tables are in a switch,
during a flow entry programming in a switch, how a flow entry is programmed
into multiple flow tables in OVS? I assume, controller may not send on what
are the tables, the flow entry needs to be programmed because controller
may not aware of it in our case. So, how OVS is able to map a single flow
entry into multiple flow tables? What logic it is using? Could you please
point the function name also ?


Thanks,
tech.kals


On Wed, Mar 11, 2015 at 7:28 AM, Ben Pfaff <blp at nicira.com> wrote:

> Exactly the same way as every other OpenFlow switch.  There is nothing
> Open vSwitch specific here.
>
> On Wed, Mar 11, 2015 at 06:54:00AM +0530, tech_kals Kals wrote:
> > Hi Ben,
> >
> >   am just asking when OVS uses multiple flow tables without
> > "OFPMP_TABLE_FEATURES".
> > How it informs the controller? how they have been used ? Just wanted to
> get
> > it clarified...
> >
> > On Tue, Mar 10, 2015 at 11:07 PM, Ben Pfaff <blp at nicira.com> wrote:
> >
> > > Your question makes no sense, because OpenFlow 1.1 and 1.2 had
> > > multiple tables (in the sense that you mean) but did not have
> > > OFPMP_TABLE_FEATURES.  Are you saying that these two versions of
> > > OpenFlow were useless?  If you are, please explain.  If you are not,
> > > then please consult their specifications for information on how to
> > > figure out the number of tables and their properties.
> > >
> > > On Tue, Mar 10, 2015 at 10:52:42PM +0530, tech_kals Kals wrote:
> > > > Hi Ben,
> > > >
> > > >   Thanks for your support.
> > > >
> > > >  I was asking about how OVS uses multiple flow table when it is not
> > > capable
> > > > of informing controller about it has support for multiple flow tables
> > > > through OFPMP_TABLE_FEATURES?
> > > >
> > > > Since OVS doesnt support OFPMP_TABLE_FEATURES then obviously
> controller
> > > may
> > > > not be knowing the switch has multiple flow tables. So, switch would
> > > assume
> > > > OVS has a single table. In this case, how OVS uses multiple flow
> tables
> > > to
> > > > map a flow entry which has been received from controller?
> > > >
> > > >
> > > > Meanwhile, *Is there an anticipated date on when OVS 2.4 will be
> > > available?
> > > > *
> > > >
> > > >
> > > > Thanks,
> > > > Kals.
> > > >
> > > > On Mon, Mar 9, 2015 at 9:39 PM, Ben Pfaff <blp at nicira.com> wrote:
> > > >
> > > > > OpenFlow 1.1 and later support the kind of multiple tables you care
> > > > > about.  Only OpenFlow 1.3 added OFPMP_TABLE_FEATURES.  You can
> consult
> > > > > the OpenFlow specifications to learn about how OpenFlow works.
> > > > >
> > > > > On Mon, Mar 09, 2015 at 09:41:08AM +0530, tech_kals Kals wrote:
> > > > > > Hi Ben,
> > > > > >
> > > > > > Thanks for your response. Even though OVS 1.3 or later is
> supporting
> > > > > > multiple flow tables. May I know what is the use of them if
> > > controller is
> > > > > > not informed about multiple flow tables through
> > > OFPMT_TABLE_FEATURES. Or
> > > > > do
> > > > > > you use some other mechanism to inform the controller about
> > > supporting
> > > > > > multiple flow tables on the switch?
> > > > > >
> > > > > >
> > > > > > Thanks,
> > > > > > Kaliyaperumal K
> > > > > >
> > > > > >
> > > > > > On Sat, Mar 7, 2015 at 1:06 PM, Ben Pfaff <blp at nicira.com>
> wrote:
> > > > > >
> > > > > > > Only OVS 2.4 supports OFPMT_TABLE_FEATURES.
> > > > > > >
> > > > > > > OVS 1.3 and later support multiple flow tables.
> > > > > > >
> > > > > > > On Sat, Mar 07, 2015 at 08:00:44AM +0530, tech_kals Kals wrote:
> > > > > > > >  In your previous reply to this thread, you had mentioned
> that
> > > OVS
> > > > > 2.4
> > > > > > > only
> > > > > > > > will support multiple flow tables. Now, you mention that it
> is
> > > > > supported
> > > > > > > in
> > > > > > > > OVS1.3 onwards.  I see, OFPMT_TABLE_FEATURES is not
> supported in
> > > OVS
> > > > > > > 2.1.0.
> > > > > > > > Do you mean, it is supported in 1.3? If it is supported in
> 1.3
> > > > > release,
> > > > > > > > then obviously it should be supported in 2.1.0 as well...
> but,
> > > not
> > > > > sure
> > > > > > > how
> > > > > > > > it is missed ?
> > > > > > > >
> > > > > > > > I am little bit confused. Could you please clarify me
> regarding
> > > > > this.?
> > > > > > > >
> > > > > > > > On Sat, Mar 7, 2015 at 2:43 AM, Ben Pfaff <blp at nicira.com>
> > > wrote:
> > > > > > > >
> > > > > > > > > On Fri, Mar 06, 2015 at 10:18:29PM +0530, tech_kals Kals
> wrote:
> > > > > > > > > > Thanks for your reply. I am planning to use OVS to
> inform the
> > > > > > > controller
> > > > > > > > > > about multiple flow support. Since any of the OVS
> versions
> > > are
> > > > > not
> > > > > > > > > > supporting Multiple flow tables support, could you please
> > > > > clarify my
> > > > > > > > > > doubts. Also, want to know if you share the details how
> OVS
> > > is
> > > > > going
> > > > > > > to
> > > > > > > > > > support multiple flow tables then it would be great for
> me
> > > to do
> > > > > my
> > > > > > > > > > design/coding.
> > > > > > > > >
> > > > > > > > > This question is bizarre.  Open vSwitch has supported
> multiple
> > > flow
> > > > > > > > > tables since 2011, in OVS version 1.3.
> > > > > > > > >
> > > > > > >
> > > > >
> > >
>