TestNon3GPP network interface help

Q/A
#1

Hello,

I am struggling to figure out how to configure my IPSec interface for a successful TestNon3GPP test.

I’m using free5gc-compose (docker setup) with the following:

  • N3IWF IP address: 10.100.200.15

And here’s my config setup in the non3gpp_test.go file for the test:

  • n3iwfInfo_IPSecIfaceAddr = “10.100.200.15”
  • n3ueInfo_IPSecIfaceAddr = “10.100.200.15”
  • n3ueInfo_SmPolicy_SNSSAI_SST = “1”
  • n3ueInfo_SmPolicy_SNSSAI_SD = “010203”
  • n3ueInfo_IPSecIfaceName = “veth3”
  • n3ueInfo_XfrmiName = “ipsec”
  • n3ueInfo_XfrmiId = uint32(1)
  • n3ueInfo_GreIfaceName = “gretun”
  • ueInnerAddr = new(net.IPNet)

Can someone explain to me what “n3iwfInfo_IPSecIfaceAddr” and “n3ueInfo_IPSecIfaceAddr” should be set to? I see by default they are set to 192.168.127.1 and 192.168.127.2 respectively. However, when I run these default parameters, my TestNon3GPP test script is unable to communicate with the N3IWF.

Are there updated instructions on properly configuring routing for the N3IWF and TestNon3GPP?

Thanks.

#3

The test script will create one namespace for the UE in the TestNon3GPP test. n3iwfInfo_IPSecIfaceAddr represents the Nwu interface IP address (IKE) on the N3IWF; it is set in the function setupN3ueEnv. And n3ueInfo_IPSecIfaceAddr represents the UE’s address, which connects to n3iwf; it’s also set in the setupN3ueEnv. So if you want to modify it, you should modify setupN3ueEnv in the test script too.

#5

If you only want to test, you don’t need to execute Docker Compose and don’t need to set the IP. When you run ./test.sh TestNon3GPP, the script will set up the environment for the n3iwf and n3ue.

#6

@Jerry I only tried the Docker Compose method because the normal ./test.sh TestNon3GPP does not work.

Let me try restarting from scratch.

I have created a new install on a fresh computer as defined here: Index - free5GC

When doing so, the ./test.sh uses n3iwfcfg.test.yaml, which tries to find the AMF at 10.200.200.1. However, the amfcfg.yaml sets the AMF ip address to 127.0.0.18.

I cannot figure out what all needs to be changed for the TestNon3GPP test to actually pass.

#2

Hello, so you execute the TestNon3GPP test in the n3iwf container? Can you describe your setting in detail? And please provide the complete log. Thank you.

#4

Thanks for the response Jerry.

The free5GC-compose doesn’t have test scripts that I can find. So I have my core running in docker, and I’m running the ./test.sh TestNon3GPP outside my containers on the same computer. Do you know of an easier way to do this?

Here is my computer’s ifconfig (outside a container):

user:~/free5gc-compose$ ifconfig
br-free5gc: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 10.100.200.1  netmask 255.255.255.0  broadcast 10.100.200.255

docker0: flags=4099<UP,BROADCAST,MULTICAST>  mtu 1500
        inet 172.17.0.1  netmask 255.255.0.0  broadcast 172.17.255.255

enp89s0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 10.10.4.189  netmask 255.255.255.0  broadcast 10.10.4.255

And here is my N3IWF ifconfig:

user@user-NUC11BTMi9:~$ docker exec -it n3iwf ifconfig
eth0      Link encap:Ethernet  HWaddr 02:42:0A:64:C8:0F  
          inet addr:10.100.200.15  Bcast:10.100.200.255  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1

ipsec0    Link encap:UNSPEC  HWaddr 0A-64-C8-0F-00-00-00-00-00-00-00-00-00-00-00-00  
          inet addr:10.0.0.1  Mask:255.255.255.0
          UP RUNNING NOARP  MTU:1480  Metric:1

lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          UP LOOPBACK RUNNING  MTU:65536  Metric:1

xfrmi-default Link encap:UNSPEC  HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00  
          inet addr:10.0.0.1  Mask:255.255.255.0
          UP RUNNING NOARP  MTU:1500  Metric:1

Based on what you said about n3ueInfo_IPSecIfaceAddr, I’ve tried changing n3ueInfo_IPSecIfaceAddr to my br-free5gc IP (10.100.200.1), but when I do that, it is unable to communicate with the N3IWF.

Are there any routes I need to manually configure? I’m just trying to get TestNon3GPP to run successfully using ANY setup right now.

Thanks.

#7

Resolving this post.

I started over from scratch and running ./test.sh TestNon3GPP passes without any config file changes at all. Overall my only guess was an incompatibility with my kernel version.

Ultimately I followed these steps: Index - free5GC

Specifically I did this:

  • Created a new VM with Ubuntu 20.04 OS. Specifically I installed Ubuntu ARM64 server 20.04. After installation I installed desktop GUI using sudo apt install ubuntu-desktop
  • Ensured my kernel was on version 5.4.x as recommended in 2 config vm en - free5GC . In my case my kernel is 5.4.0-169-generic
#9