How to specify which UPF is used as a default

Q/A
,
#1

Hello,

Would you let me know the way to configure which route packet will take as a default, when we are using ULCL.

I’d like to separate the route between specific IP address and others.
For example, the packet for website A pass through UPF1 and others pass through UPF2.
Is it possible to set the default route for the packet which were not written in uerouting.yaml?

I will attach some config files.
In this case, we couldn’t specify the default route of UPF.
Sometimes UPF1 was used, and sometimes UPF2 was used.

Thank you for your help.

upf1cfg.ulcl.yaml (933 Bytes) upf2cfg.ulcl.yaml (931 Bytes) upfbcfg.ulcl.intranet.yaml (931 Bytes) smfcfg.ulcl.yaml (6.6 KB) uerouting.yaml (3.1 KB)

#2

Hi @NK636, in smf/producer/pdu_session.go function HandlePDUSessionSMContextCreate, during data path selection, UE will use default route if it has no pre-config path. In the code, it will choose the UPF selected by smf (UPF selection). If you want all of the non specific IP address packet use a specific default UPF, maybe you can try editing the code as I mention above, select a UPF by your own instead of selected by SMF.

#3

Hi @oommcclee,

Thank you for your response.

I understood that SMF will select the UPF in smf/producer/pdu_session.go, and I need to edit the code to fix which UPF is used as default.

I have expected that the default route of UPF is set by using config files, but is it impossible?
I thought there might be a possibility that we need to change the default route after installing free5gc.

I appreciate your help.

#4

Hi @NK636,
I’m sorry, our implementation do not support setting default route by config files now. So i think the only solution is edit the code, and we will plan to fix this problem in the future, thanks for your report!

#5

Hi @oommcclee,
I appreciate your response.

I understood that editing source code is the only way to fix the default route now.
I will check HandlePDUSessionSMContextCreate in smf/producer/pdu_session.go.

Thank you for considering the fix. I’ll be waiting for the good news.

#6