UE Connection State Not Updating

General Discussions
#1

Hello,

I am running UERANSIM with the latest version of the free5GC core. I am doing some stress testing of the core, connecting multiple UEs at once, and have noticed some odd behavior with the core.

If I connect a UE and gain a PDU session, and then look at the Realtime stats in the webui, I can see the UE says ‘CONNECTED’ which makes sense. The issue is that once I quit the UE program, It shows in the gNB program that it has lost signal from the UE, but the Core webui still indicates the UE is connected, when it is not.

This can create problems when connecting and disconnecting the UE, as sometimes it refuses to get a PDU session due to a mismatch state.

Any thoughts would be helpful. Thanks.

#2

I tried it with free5gc-compose. I think the issue is that UERANSIM doesn’t send a state change signal (possibly a deregistration signal) to free5GC when I terminate the UE using ctrl-c.

#3

If you use ./nr-cli command line interface to deregister UE properly, you’ll see the message in free5gc like the one shown:

image
image1318×385 129 KB

UERANSIM usage tutorial: https://github.com/aligungr/UERANSIM/wiki/Usage
I used disable-5g to deregister the UE. After that this UE information disappeared from webui Realtime page.