Re: Ask about Segment routing in Trellis

[Charles Chan]

Hi Van,

You can find a list of supported topologies here:
https://docs.trellisfabric.org/supported-topology.html

Thanks,

Charles Chan, Ph.D.

Member of Technical Staff, Open Networking Foundation

On Fri, Oct 11, 2019 at 6:42 AM Van Tong <tongva...@gmail.com> wrote:

Hi Charles,

I am sorry to bother you.

Thank you for your support in a post of ONOS Developers (https://groups.google.com/a/onosproject.org/forum/#!topic/onos-dev/MKKXSMpKylI).

After your instruction, I studied Trellis and implemented segment routing via the link: https://github.com/opennetworkinglab/routing/tree/master/trellis, and I have a question related to the topology in the experiment.

Can we create another kind of the topology in segment routing?

I mean that we only have the link between the leaf node and the spine node (leaf-spine) in the experiment.

Can we have the link between the leaf node and the leaf node (leaf-leaf) or the spine node and the spine node (spine-spine)?

I tried with another topology that have the leaf-leaf and spine-spine links, but it does not work. I can not ping between 2 hosts.

I am looking forward to hearing the response from you.

Thank you in advance.

Best regards,

Van

Van Van Tong

[Charles Chan]

(+ trellis-dev. Please do not drop the mailing list)

Hi Van,

Which switch are you using? OVS or hardware?
The ECMP hashing function is implemented differently among switches, but typically they use 5-tuples. I haven't noticed a similar issue in the past. How did you conduct your experiment?

Thanks,

Charles Chan, Ph.D.

Member of Technical Staff, Open Networking Foundation

On Thu, Oct 24, 2019 at 1:54 PM Van Tong <tongva...@gmail.com> wrote:

Dear Charles,

 

I am sorry to bother you again.

After implementing the experiments with segment routing (SR) application in ONOS, I found out that there is a difference between the experiments of TCP and UDP.

When I forward the TCP packets from a source to a destination, SR application forwards the packets through only one routing path in the normal network condition. However, SR application forwards the UDP packets through many equal-cost multi-paths in the same network condition.

Do you know why there is a difference between the experiments of TCP and UDP?