Numan Siddique <nusid...@redhat.com> wrote on 08/09/2016 09:39:21 AM:
> From: Numan Siddique <nusid...@redhat.com> > To: Ryan Moats/Omaha/IBM@IBMUS > Cc: ovs dev <dev@openvswitch.org> > Date: 08/09/2016 09:39 AM > Subject: Re: [ovs-dev] [PATCH] ovn-controller: Reset flow processing > after (re)connection to switch > > On Tue, Aug 9, 2016 at 7:15 PM, Ryan Moats <rmo...@us.ibm.com> wrote: > "dev" <dev-boun...@openvswitch.org> wrote on 08/09/2016 07:19:27 AM: > > > From: Numan Siddique <nusid...@redhat.com> > > To: ovs dev <dev@openvswitch.org> > > Date: 08/09/2016 07:19 AM > > Subject: [ovs-dev] [PATCH] ovn-controller: Reset flow processing > > after (re)connection to switch > > Sent by: "dev" <dev-boun...@openvswitch.org> > > > > When ovn-controller reconnects to the ovs-vswitchd, it deletes all the > > OF flows in the switch. It doesn't install the flows again, leaving > > the datapath broken unless ovn-controller is restarted or ovn-northd > > updates the SB DB. > > > > The reason for this is > > - lflow_reset_processing() is not called after the reconnection > > - the hmap "installed_flows" is not cleared, because of which > > ofctrl_put skips adding the flows to the switch. > > > > This patch fixes the issue and also adds a test case to test > > this scenario. > > > > Signed-off-by: Numan Siddique <nusid...@redhat.com> > > --- > > I'm going to pick a nit on this one - is the behavior you are aiming > for delete and re-add or just recalculate and leave alone? > > In my testing I am seeing that all the OF flows are getting de > leted when I restart ovs-vswitchd. > I am testing with the latest master of OVS. I am able to see this on > 2 different machines and also in sandbox. > > I thought that ovn-controller is deleting the flows in the switch > when it restarts (https://github.com/openvswitch/ovs/blob/master/ > ovn/controller/ofctrl.c#L355) > > Now I tested again and before restarting ovs-vswitchd, I killed ovn- > controller. Looks like ovs-vswitchd is clearing the old flows when > it restarts. I am not sure if this is the intended behavior. Looks > like it is. Please correct me if I am wrong here. > > You can run below commands to reproduce the issue in sandbox > > ----------------------------- > $make sandbox SANDBOXFLAGS="--ovn" > $ovn/env1/setup.sh > $ovs-ofctl dump-flows br-int > $ovs-appctl -t ovn-controller exit > $ovs-appctl -t ovs-vswitchd exit > $ovs-vswitchd --detach --no-chdir --pidfile -vconsole:off --log- > file --enable-dummy=override -vvconn -vnetdev_dummy > $ ovs-ofctl dump-flows br-int > NXST_FLOW reply (xid=0x4): > ------------------------------------ > > You will see that the flows are deleted even if you don't run - > "ovs-appctl -t ovn-controller exit". > > I ask because if it is "delete and re-add" aren't you still disrupting > the datapath even if only momentarily? > Ok, so we'll assume that your code is valid for when ovswitchd purges the old flows and that's good. IIRC there is a way to restart ovswitchd via ovs_ctl so that it doesn't purge the old flows. Since I'll argue (as an operator) that is the more important case, can you add a unit test for this and verify that your patch doesn't leave that path broken? _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev
