How would the controller tell the switch what to use?
On Mon, Apr 17, 2017 at 07:03:44AM +0000, Ali Volkan Atli wrote: > From SDN point of view, the of-switch should be dump but when > I evaluate the spec and also your answer, the aux connection is > breaking the issue. > > A controller has no way of telling of-switch what connection will be used, > the of-switch can decide what it wants. This does not make sense to me. > > - Volkan > ________________________________________ > From: Ben Pfaff [b...@ovn.org] > Sent: Sunday, April 16, 2017 7:43 PM > To: Ali Volkan Atli > Cc: disc...@openvswitch.org > Subject: Re: [ovs-discuss] How to use auxiliary connnection > > On Sun, Apr 16, 2017 at 11:30:33AM +0000, Ali Volkan Atli wrote: > > I am trying to understand auxiliary connection according to OpenFlow 1.5 > > specifications but I have some questions as follows > > > > 1) Let's suppose I have one main and one auxiliary connection. How > > does the controller decide (or force) which connection to use for > > sending packet-in messages? > > The OpenFlow specification says: > > The controller is free to use the various switch connections for > sending OpenFlow messages at its entire discretion, however to > maximise performance on most switches the following guidelines are > suggested: > > • All OpenFlow controller requests which are not Packet-out > (flow-mod, statistic request...) should be sent over the main > connection. > > • Connection maintenance messages (hello, echo request, features > request) should be sent on the main connection and on each auxiliary > connection as needed. > > • All Packet-Out messages containing a packet from a Packet-In > message should be sent on the connection where the Packet-In came > from. > > • All other Packet-Out messages should be spread across the various > auxiliary connections using a mechanism keeping the packets of a > same flow mapped to the same connection. > > • If the desired auxiliary connection is not available, the > controller should use the main connection. > > > 2) If the switch will decide, how will it decide? In one case, if > > there is an auxiliary connection, then -by default- all packet-ins are > > sent over "only" the aux channel? Is this correct behavior? > > The OpenFlow specification says: > > The switch is free to use the various controller connections for > sending OpenFlow messages as it wishes, however the following > guidelines are suggested : > > • All OpenFlow messages which are not Packet-in should be sent over > the main connection. > > • All Packet-In messages spread across the various auxiliary > connection using a mechanism keeping the packets of a same flow > mapped to the same connection. > > > 3) If there are multiple auxiliary connections, should the switch > > spread across the various auxiliary connection (for example for load > > balancing) > > Same question applies. _______________________________________________ discuss mailing list disc...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-discuss