[ovs-discuss] Question on using TCP transport keep alive for ovsdb connection when possible.

[Ben Pfaff]

If the application is extremely slow, then the connection is effectively
dead, and we might as well drop it anyway.

On Mon, Mar 06, 2017 at 06:53:51PM +0000, Hexin Wang wrote:
> Hi Ben,
> 
> TCP keep alive gives a good alternative to use cases where there is no firewall or proxy concern. Transport level keep alive is good enough for ovsdb to determine if connection is alive or not, without worrying if application is slow (or extremely slow) in open flow echo reply. 
> 
> Can we working on pushing this into ovs release?
> 
> Thanks.
> 
> Hexin
> 
> 
> 
> On 3/2/17, 3:57 PM, "Ben Pfaff" <blp at ovn.org> wrote:
> 
> >We used application-level echo request and replies instead, because they
> >are reliable even if a TCP connection passes through a firewall or proxy
> >that does not properly pass through TCP keepalives.
> >
> >On Thu, Mar 02, 2017 at 11:48:04PM +0000, Hexin Wang wrote:
> >> Hi Ben,
> >> 
> >> What is the reason that it is not getting to the main release? This seems the right keep alive mechanism for neutron to talk to ovn database, if they are not running on the same host/container and would have to use tcp as the transport.
> >> 
> >> Thanks.
> >> 
> >> Hexin
> >> 
> >> 
> >> 
> >> 
> >> On 3/2/17, 3:45 PM, "Ben Pfaff" <blp at ovn.org> wrote:
> >> 
> >> >On Thu, Mar 02, 2017 at 11:43:01PM +0000, Hexin Wang wrote:
> >> >> I have a question on the following patch that use TCP keep alive for ovsdb connection.
> >> >> 
> >> >> https://mail.openvswitch.org/pipermail/ovs-dev/2011-April/251891.html
> >> >> 
> >> >> Did this patch go into ovs main release?
> >> >
> >> >No.