[ovs-discuss] Query regarding Bundle Commit and Rollback

[Ben Pfaff]

On Wed, Feb 18, 2015 at 02:49:12PM +0530, Chethan C R wrote:
> I am currently investigating on the implementation of OF 1.4 bundles.
> 
> Per Spec, the implementation should be able to support at least port mod
> and flow mod in any order.
> 
> However, its not clear about handling commands which will modify multiple
> matching flows. For example, a flow mod with delete on OFPTT_ALL will
> trigger a lot of churn in the openflow flow tables. To support rollback, we
> need to be backing up a considerable amount of data.
> 
> When the switch has tables spread across SW and HW, keeping a staging area
> where the bundle messages are applied may not be straight forward.
> 
> I am curious to know how the commit and rollback logic is handled and if
> these scenarios are thought of.

The bundle requests aren't supported yet.  When they are, though, it's
pretty important to handle general-purpose rollback.  Jarno has done
some preliminary work on bundle support, so I'm bringing him into the
conversation to share his thoughts.

Hardware support isn't a priority because no one has ever contributed
support for a hardware platform.