Re: proposed example text and question on draft-ietf-rtgwg-policy-model

["Acee Lindem (acee)" <[e-mail]>]

Hi Yingzhen,

Meant to reply earlier. Thanks for responding.

From: Yingzhen Qu <[e-mail]>
Date: Thursday, June 18, 2020 at 6:59 PM
To: Chris Bowers <[e-mail]>, "[e-mail]" <[e-mail]>, Routing WG <[e-mail]>
Subject: Re: proposed example text and question on draft-ietf-rtgwg-policy-model
Resent-From: <[e-mail]>
Resent-To: <[e-mail]>, Jeff Tantsura <[e-mail]>, Acee Lindem <[e-mail]>, Xufeng Liu <[e-mail]>
Resent-Date: Thursday, June 18, 2020 at 6:59 PM

Hi Chris,

Thanks for the review and proposed examples, really appreciate.

I’ve uploaded a new version of the draft and included the example to demonstrate route redistribution between ospf and isis. I didn’t include the one to install ospf routes to RIB considering this is default behavior unless you specify a policy to limit the ospf routes installation.

Regarding the name, the model supports both import and export modes, so I didn’t want to simply change the name to “set-export-level”, but open to suggestions. The model also provides a grouping “apply-policy-group” that can be used by routing protocols for route redistributions, and there are descriptions about it in Section 6.

I Think we should change it to set-isis-level or simply set-level.

Thanks,
Acee


Thanks,
Yingzhen

From: Chris Bowers <[e-mail]>
Date: Wednesday, June 10, 2020 at 2:23 PM
To: "[e-mail]" <[e-mail]>, "[e-mail]" <[e-mail]>
Subject: proposed example text and question on draft-ietf-rtgwg-policy-model
Resent-From: <[e-mail]>
Resent-To: <[e-mail]>, <[e-mail]>, <[e-mail]>, <[e-mail]>
Resent-Date: Wednesday, June 10, 2020 at 2:23 PM

I would like to propose adding the following example to the text of draft-ietf-rtgwg-policy-model
to better illustrate how the model will work in practice with routing policies involving IGPs.
The proposed text is shown below.

I think that the example below also illustrates a problem with the naming of what is currently called "import-level" and "set-import-level".  In the example, the export policy called "export-all-OSPF-prefixes-into-ISIS-level-2" uses the "set-import-level"  action.  As far as I can tell, it only makes sense to use "set-import-level" in an export policy, and not in an import policy.  If this is the case, wouldn't it make more sense to call it "set-export-level"?

===========
Proposed text for new IGP routing policy example:

This example illustrates the import and export policies corresponding to the following scenario.
All routes that are learned via OSPF advertisements should get installed in the RIB.
All routes in the RIB that have been learned from OSPF advertisements corresponding to
OSPF intra-area and inter-area route types should get advertised into ISIS level 2 advertisements.

          <policy-definitions>
           <policy-definition>
             <name>import-all-OSPF</name>
             <statements>
               <statement>
                 <name>term-0</name>
                 <conditions>
                   <match-prefix-set>
                     <prefix-set>all-prefixes</prefix-set>
                   </match-prefix-set>
                 </conditions>
                 <actions>
                   <policy-result>accept-route</policy-result>
                 </actions>
               </statement>
             </statements>
           </policy-definition>
              <policy-definition>
             <name>export-all-OSPF-prefixes-into-ISIS-level-2</name>
             <statements>
               <statement>
                 <name>term-0</name>
                 <conditions>
                   <match-prefix-set>
                     <prefix-set>all-prefixes</prefix-set>
                   </match-prefix-set>
                   <match-route-type>
                     <proto-route-type>ospf-internal-type</proto-route-type>
                   </match-route-type>
                 </conditions>
                 <actions>
                   <set-import-level>
                     <import-level>isis-level-2</import-level>
                   </set-import-level>
                   <policy-result>accept-route</policy-result>
                 </actions>
               </statement>
             </statements>
           </policy-definition>
         </policy-definitions>

==========

Thanks,
Chris