Build according to instructions failed

Q/A
#1

Hi,

not much of a programmer but can speak fluently 3GPP TS’ish. I tried to setup it up on a clean ubuntu according to | free5GC When I run the AMF it gives and error about the NGAP (probably because there is no corresponding gNB). When i then tried to install the UPF, the make -j nproc gave many errors regarding to N4 and PFCP support (not SBI core network interface, so this is the protocol that replaces the S1_C from 4G). The look like this:

/home/myname/go/src/free5gc/src/upf/src/n4/n4_pfcp_handler.c:488:52: error: taking address of packed member of ‘struct _PfcpOuterHdr’ may result in an unaligned pointer value [-Werror=address-of-packed-member]
488 | 0, &(outerHdr->addr4),
| ^~~~~~~~~~~~~~~~~~
Any help appreciated, and best on “for dummies level”, but feel free to ask me about how a mobile network works…

here the final “verdict” of the make:
make[2]: *** [src/CMakeFiles/free5GC_UPF_main.dir/build.make:89: src/CMakeFiles/free5GC_UPF_main.dir/n4/n4_pfcp_handler.c.o] Error 1
make[1]: *** [CMakeFiles/Makefile2:168: src/CMakeFiles/free5GC_UPF_main.dir/all] Error 2
make: *** [Makefile:84: all] Error 2

#2

I found that you followed up the stage 2 of free5GC. And I guess that you run that on a Ubuntu newer than 18.04 (since it’s 2021 now)?
Usually it’s your best bet to run exactly the same version as recommend.
And maybe you can also try stage 3 with Ubuntu 20.04.

#3

Hi John, thanks for the help and anser. I used Ubuntu 20.04 and started clean. I would need stage 2 for my task. But as said, I think the problem lies in the build of the N4 interface modules and the lower protocols there.

#4

It seems that all versions mentioned, need to be exactly like that. Including, the Ubuntu 18.04 kernel, the kernel needs to be 5.0.0-23-generic. Not 5.4 whatever.