[openstack-dev] [ovs-discuss] [OVN] [networking-ovn] [networking-sfc] SFC andOVN

John McDowall jmcdowall at paloaltonetworks.com
Wed Jun 15 22:58:35 UTC 2016


Ryan,

In-line

Regards

John

From: Ryan Moats <rmoats at us.ibm.com<mailto:rmoats at us.ibm.com>>
Date: Tuesday, June 14, 2016 at 9:42 PM
To: John McDowall <jmcdowall at paloaltonetworks.com<mailto:jmcdowall at paloaltonetworks.com>>
Cc: Na Zhu <nazhu at cn.ibm.com<mailto:nazhu at cn.ibm.com>>, Srilatha Tangirala <srilatta at us.ibm.com<mailto:srilatta at us.ibm.com>>, "OpenStack Development Mailing List (not for usage questions)" <openstack-dev at lists.openstack.org<mailto:openstack-dev at lists.openstack.org>>, discuss <discuss at openvswitch.org<mailto:discuss at openvswitch.org>>
Subject: Re: [ovs-discuss] [openstack-dev] [OVN] [networking-ovn] [networking-sfc] SFC andOVN


"discuss" <discuss-bounces at openvswitch.org<mailto:discuss-bounces at openvswitch.org>> wrote on 06/14/2016 10:31:40 PM:

> From: John McDowall <jmcdowall at paloaltonetworks.com<mailto:jmcdowall at paloaltonetworks.com>>
> To: Na Zhu <nazhu at cn.ibm.com<mailto:nazhu at cn.ibm.com>>
> Cc: Srilatha Tangirala/San Francisco/IBM at IBMUS, "OpenStack
> Development Mailing List \(not for usage questions\)" <openstack-
> dev at lists.openstack.org<mailto:dev at lists.openstack.org>>, discuss <discuss at openvswitch.org<mailto:discuss at openvswitch.org>>
> Date: 06/14/2016 10:48 PM
> Subject: Re: [ovs-discuss] [openstack-dev] [OVN] [networking-ovn]
> [networking-sfc] SFC andOVN
> Sent by: "discuss" <discuss-bounces at openvswitch.org<mailto:discuss-bounces at openvswitch.org>>
>
> Juno,
>
> It is a container for port-pair-groups and flow-classifier. I
> imagine there could be more the than one port-chain per switch. Also
> we may want to extend the model beyond a single lswitch

I agree that there could be more than one port-chain per switch, determined
by the flow classifier.

What I'm confused by is:

1. Why are items only recorded in logical switches?  I would think
that I could also attach an SFC to a logical router - although I admit
that the current neutron model for ports doesn't really allow that
easily.  Couple that with the change of name from Logical_Port to
Logical_Switch_Port, and I'm left wondering if we aren't better off
with the following "weak" links instead:
-the Port_Chain includes the logical switch as an external_id
-each Port_Pair_Group includes the Port_Chain as an external_id
-each Port_Pair includes the PPG as an external_id
-each Logical_Switch_Port includes the PP as an external_id

I *think* that *might* allow me (in the future) to attach a port chain
to a logical router by setting the logical router as an external_id and
using Logical_Router_Ports to make up the PPs...

JED> If there are "port-chain" tables for switches and routers I think I agree. Not sure how this is impacted by the type of VNF (see the last email to Juno). I struggle a bit with imagining the flows.

2. I still don't see what Logical_Flow_Classifier is buying me that
ACL doesn't - I can codify all of the classifiers given in the match
criteria of an ACL entry and codify the first PPG of the SFC as
the action of the ACL entry...

JED> Flow classifiers do map to an ACL entry - just need additional metadata, I.e. Action of the ACL and wether the rules should be uni or bi-directional. Though that information could be in the port-chain.

Ryan
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstack.org/pipermail/openstack-dev/attachments/20160615/a28c9c5e/attachment.html>


More information about the OpenStack-dev mailing list