[ovs-discuss] Apply some packet manipulation actions on outgoing port traffic

Juraj Markotic juraj.markotic at gmail.com
Mon Oct 9 20:45:10 UTC 2017


I will check on about GTP ongoing activities (I saw some actitvities on
providing capabilities to match on GTP-C/GTP-U packets).
maybe dumb question, but any pointer on how to remove GRE header (or VXLAN
for that matter) when switching packet from IN port to OUT port and switch
out only internal packet/payload ?
thanks,
jm


On Mon, Oct 9, 2017 at 10:13 PM, Ben Pfaff <blp at ovn.org> wrote:

> OVS doesn't support GTP yet, but I know that there's some ongoing work
> on it.
>
> GRE and VXLAN should be fine.
>
> If you need GTP support, maybe the best thing to do would be to help out
> the folks who are working on it.
>
> On Mon, Oct 09, 2017 at 09:35:42PM +0200, Juraj Markotic wrote:
> > Hello,
> > thanks for feedback.
> > I know OVS can truncate payload and that in can modify mac/IPs in header
> > (i.e. like doing NAT).
> > I also know OVS can deencapsulate GRE (of VXLAN) when packet is arriving
> on
> > tunnel OVS interface (done automatically).
> > But I was not aware that OVS can remove tunnel headers when switching
> > incoming GTP/GRE/VXLAN header and extract inside packet (with totally new
> > src/dst ip) and send it out.
> > Can you share some OVS cli example for such ?
> > we have network packet broker (NPB) with OVS, so if NPB is delivering
> > tunnel packets, it would be great if we could remove tunnel headers
> before
> > delivering it to the (monitoring) tool on outgoing port.
> >
> > thanks,
> > jm
> >
> > On Mon, Oct 9, 2017 at 6:31 PM, Ben Pfaff <blp at ovn.org> wrote:
> >
> > > On Sun, Oct 08, 2017 at 11:19:17PM +0200, Juraj Markotic wrote:
> > > > we would need some functionality on manipulating packets when packet
> is
> > > > exiting outgoing OVS port.
> > > > I.e. some actions could be: change/anonymize mac/IPs for src/dst, or
> > > remove
> > > > some tunnel header (vxlan, gtp, gre), truncate the payload etc.
> > >
> > > OVS has actions for modifying headers and it can decapsulate tunnels
> and
> > > truncate payloads.
> > >
> > > > So, one option can be to write some code than can be attached to OVS
> to
> > > > packet exiting out port (i.e. some lua scripts for manipulation).
> > >
> > > Lua isn't needed.  You can use OpenFlow.
> > >
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.openvswitch.org/pipermail/ovs-discuss/attachments/20171009/fead6eb6/attachment-0001.html>


More information about the discuss mailing list