On 1/7/26 07:08, 'Md Sharif Hossen' via Powder Users wrote:
> Hi POWDER Team,
>
> I am currently running an experiment with one LTE base station and one
> UE. While following the provided instructions, I found that the NexRAN
> slicing xApp is not working as expected in my experiment, and I am not
> receiving any KPIs in Grafana. I am not sure whether this issue is
> related to the KPI subscription or another configuration problem, but I
> am seeing the attached error.
>
> My experiment link is:
>
https://www.powderwireless.net/status.php?uuid=0d477155-e2db-11f0-bc80-
> e4434b2381fc
>
> I also have a few additional questions:
>
> 1. Does the current O-RAN experiment support two base stations and two
> UEs? If yes, could you please provide the link to the relevant
> instructions or documentation?
The environment supports it, but we have not yet updated the "sidecar"
profile (
https://www.powderwireless.net/p/PowderTeam/srslte-shvlan-oran)
that allocates multiple gnb/UEs in the POWDER RF attenuator matrix to
install and configure srsRAN 5G. So there would be a bit of work to
update the "sidecar" profile.
> 2. I see an srsLTE-based O-RAN experiment. Is there any O-RAN experiment
> available that supports srsRAN or OAI 5G?
Yes. Please use the `u24-update` branch of the O-RAN profile to try the
5G version. It provides different instructions. When you are looking
at the O-RAN profile page
(
https://www.powderwireless.net/show-profile.php?project=PowderProfiles&profile=O-RAN),
scroll to the bottom. You will see two branches. Click `Instantiate`
to the right of the branch.
> 3. Is there any sample xApp (other than the slicing xApp) that I can use
> to extract KPIs?
You could try the OSC kpimon xApp, but I experienced a build failure
last time I tried to use it, and haven't been able to get back to it yet.
> 4. Could you please share guidance on the NexRAN xApp source code? My
> goal is to modify the code, rebuild it, and run my own xApp. Are there
> any instructions or recommended workflow to follow?
Sure, the source code is here:
https://gitlab.flux.utah.edu/powderrenewpublic/nexran/-/tree/dev?ref_type=heads
(make sure you are looking at the `dev` branch, as the link will take
you to). `master` currently still has the 4G custom service model version.
> 5. Is there any O1 interface in the ORAN experiment to collect the KPIs?
> If yes, how can I use it?
No, last I looked, srsRAN does not yet support the O1 interface. I'm
not sure what their timeline for that might be.
> Sharif
> PhD Student, NCSU
David