Re: [i2rs] Problem using rib-data-model RPC with rib-info-model Information (draft-ietf-i2rs-rib-data-model-05 + draft-ietf-i2rs-rib-info-model-08)

[Edwin Cordeiro <[e-mail]>]

Hi Mach,

I mean the RIB should have a group of a nexthops and a group of routes and
while the draft stated nexthop as part of the route.

I my understanding each route would indicate which of the existing nexthops
it uses, allowing a nexthop to be shared by multiple routes without having
multiple copies of the same next hop.

I don't think my statement contradicts your understand.

Best Regards,


Edwin Cordeiro

On Mon, Jun 27, 2016 at 4:22 AM, Mach Chen <[e-mail]> wrote:

> Hi Edwin,
>
>
>
> Could you elaborate more about the mean of “nexthops should be handled
> separated to routes” ?
>
>
>
> In my understanding, the nexthop-add/delete RPC s are designed to operate
> the nexthop separately.  Of cause, a nexthop list node should be added to
> the rib, hence to maintain the added nexthops.
>
>
>
> Best regards,
>
> Mach
>
>
>
> *From:* Edwin Cordeiro [mailto:[e-mail]]
> *Sent:* Saturday, June 25, 2016 3:25 PM
> *To:* Mach Chen
> *Cc:* i2rs
> *Subject:* Re: [i2rs] Problem using rib-data-model RPC with
> rib-info-model Information (draft-ietf-i2rs-rib-data-model-05 +
> draft-ietf-i2rs-rib-info-model-08)
>
>
>
> Hi Mach,
>
>
>
> Thanks for the explanation. We thought that nexthops should be handled
> separated to routes, but that wasn't reflected in the draft.
>
>
>
> Best Regards,
>
>
>
>
> Edwin Cordeiro
>
>
>
> On Fri, Jun 24, 2016 at 5:08 AM, Mach Chen <[e-mail]> wrote:
>
> Hi Edwin,
>
>
>
> Thanks for your great question!
>
>
>
> I think this is a bug of the current model, there should be a list in a
> rib to maintain the nexthops of the rib.
>
>
>
> Regarding your question: “How can we add a Nexthop without informing the
> parent Route?” Yes, a nexthop can be created without informing the parent
> routes. In the current design, the nexthop is decoupled from the routes. A
> nexthop can be shared by multiple routes or is dedicated to a single route.
>
>
>
> Best regards,
>
> Mach
>
>
>
> *From:* i2rs [mailto:[e-mail]] *On Behalf Of *Edwin Cordeiro
> *Sent:* Wednesday, June 22, 2016 3:44 PM
> *To:* i2rs
> *Subject:* [i2rs] Problem using rib-data-model RPC with rib-info-model
> Information (draft-ietf-i2rs-rib-data-model-05 +
> draft-ietf-i2rs-rib-info-model-08)
>
>
>
> Hello all,
>
>
>
> When trying to implement I2RS we are faced the following problem:
>
>
>
> In draft-ietf-i2rs-rib-data-model-05#section-2.5 the RPC offer the
> following Nexthop operations:
>
>       +---x nh-add
>
>       |  +---w input
>
>       |  |  +---w rib-name              string
>
>       |  |  +---w nexthop-id?           uint32
>
>       |  |  +---w sharing-flag?         boolean
>
>       |  |  +---w (nexthop-type)?
>
>       |  |     ...
>
>       |  +--ro output
>
>       |     +--ro result        uint32
>
>       |     +--ro reason?       string
>
>       |     +--ro nexthop-id?   uint32
>
>       +---x nh-delete
>
>          +---w input
>
>          |  +---w rib-name              string
>
>          |  +---w nexthop-id?           uint32
>
>          |  +---w sharing-flag?         boolean
>
>          |  +---w (nexthop-type)?
>
>          |     ...
>
>          +--ro output
>
>             +--ro result uint32
>
>             +--ro reason? string
>
>
>
> In these operations the Nexthop is directly connected to a RIB, but
> in draft-ietf-i2rs-rib-info-model-08#section-2: RIB(s) contains Route(s)
> and Route(s) contains Nexthop(s):
>
>
>
>             routing-instance
>
>             |             |
>
>             |             |
>
>       0..N  |             | 1..N
>
>             |             |
>
>         interface(s)     RIB(s)
>
>                           |
>
>                           |
>
>                           | 0..N
>
>                           |
>
>                         route(s)
>
>                         | | |
>
>               +---------+ | +----------+
>
>               |           |            |
>
>          0..N |           |            |
>
> route-attribute         match         nexthop
>
>                           |
>
>                          ...
>
>
>
> Our questions are:
>
> - How can we add a Nexthop without informing the parent Route?
>
> - Looking at the RIB grammar (draft-ietf-i2rs-rib-info-model-08#section-6)
> the Nexthop is also attached to a Route. Shouldn't Nexthop be part of RIB?
> Maybe something like:
>
>
>
>   <rib> ::= <RIB_NAME> <rib-family>
>
>                       [<route> ... ]
>
>                       [<nexthop> ...]
>
>                       [ENABLE_IP_RPF_CHECK]
>
>
>
>             routing-instance
>
>             |      |
>
>             |      |
>
>       0..N  |      | 1..N
>
>             |      |
>
>     interface(s)  RIB(s)
>
>                    |  | 0..N
>
>                    |  +--------------+
>
>               0..N |                 |
>
>                    |                 |
>
>                  route(s) ------> nexthop(s)
>
>                  | |       1..N
>
>        +---------+ |
>
>        |           |
>
>   0..N |           |
>
> route-attribute  match
>
>                    |
>
>                   ...
>
>
>
> If we misunderstood the model, could someone please explain why our
> understanding is incorrect?
>
>
>
> Best Regards,
>
>
> Edwin Cordeiro
>
>
>