[ovs-discuss] why 'ovs-vsctl add-port br dev' DO NOT check dev is really exist or not ?

[Ben Pfaff]

When you configure ovs-vsctl to connect remotely with --db= and
configure the remote ovsdb-server to listen with --remote or "ovs-appctl
-t ovsdb-server ovsdb-server/add-remote".

On Mon, Apr 27, 2015 at 11:36:58PM +0800, ZY wrote:
> Thank you  Ben
> In what kind of scenario,  ovs-vsctl will run on a different machine as ovs-vswitchd ? How dose ovs-vsctl connect to the remote ovsdb server?
> A example will really help.  Great appreciate
> 
> 
> Best Regards    
> 
> 
> 
> 
> 
> 
> 
> At 2015-04-27 23:12:09, "Ben Pfaff" <blp at nicira.com> wrote:
> >On Mon, Apr 27, 2015 at 08:02:01PM +0800, ZY wrote:
> >>     Reproduce
> >>     1.  VM-1 is binding with tap: tape502841a-f4
> >>     2.  when machine reboot,  OVS service is down first and the info of tape502841a-f4  is store in ovs-db
> >>     3.  libvirt destory the instance and delete  tape502841a-f4
> >>     4.  machine start and bootup the OVS service,  OVS read the ovs-db and will add-port br-int  tape502841a-f4, but failed to add into datapath because  tape502841a-f4 is not create yet.
> >
> >There's no "add-port" happening, it's just that the database still has
> >the same contents as before reboot.
> >
> >>     5. libvirt start instance and create  tape502841a-f4
> >>     6. the network service of instance is not work because of  tape502841a-f4 is not in datapath 
> >> 
> >> 
> >>     This lead to the PORT is different between ovs-db and ovs-datapath, and i have to restart ovs service to make it work.
> >>     I am wonder why OVS do not check the DEV is really exist in system first when run 'ovs-vsctl add-port BRIDGE DEV'  ?   and How to solve this problem?
> >
> >ovs-vsctl is just a database interface.  It doesn't know anything about
> >your system interface; in general, it cannot, because it does not
> >necessarily run on the same machine as ovs-vswitchd.
> >
> >You might want to configure OVS to remove all the bridges on reboot.