[ovs-discuss] Can I add parameters to NetFlow module bypassing the database?

[Ben Pfaff]

On Sat, Mar 28, 2015 at 02:06:54PM -0700, Hao Wu wrote:
>    I add a bloom filter struct into the netflow module, /ofproto/netflow.c.
> Now I insert items into the bloom filter through command ovs-vsctl, as the
> same way to update the parameters in netflow module, like active_timeout or
> targets, etc.. But I find the parameters are written into the ovs database
> first, under ovs-vsctl command, then sent to the netflow module, in which
> the update throughput is too slow. Is there any way that I can add items
> into my bloom filter directly and bypass the database? like the way to add
> flow item into flow table? Many thanks.

You can add support through OpenFlow messages.  See the FAQ for a
starting point:

### Q: How do I implement a new OpenFlow message?

A: Add your new message to "enum ofpraw" and "enum ofptype" in
   lib/ofp-msgs.h, following the existing pattern.  Then recompile and
   fix all of the new warnings, implementing new functionality for the
   new message as needed.  (If you configure with --enable-Werror, as
   described in [INSTALL.md], then it is impossible to miss any warnings.)

   If you need to add an OpenFlow vendor extension message for a
   vendor that doesn't yet have any extension messages, then you will
   also need to edit build-aux/extract-ofp-msgs.