As we now run a recent Linux Kernel (4.14, "T583: Upgrade to Linux Kernel 4.14 for supporting latest hardware on the market") a problem arised which is present in xl2tpd 1.3.6 shipped in Debian Jessie (https://github.com/xelerance/xl2tpd/issues/147 "l2tp does not work with 4.15 mainline kernels").
In order to fix this, xl2tps has to be upgraded to a version including this commit: https://github.com/xelerance/xl2tpd/commit/cc909bbb20d3e6e216c3d11e0f328ff906f289a8
The next xl2tpd version will be 1.3.12 but this patch can also be backported to xl2tpd 1.3.6.
My question @dmbaturin @UnicronNL is as follows, how to add those modifications/changes to the VyOS build environment?
a) Fork xl2tpd and backport that patch to the debian/jessie branch? (tested by me)
b) Compile xl2tpd 1.3.12 from source using (debuild -b -us -uc) on VyOS Jenkins (tested by world but not yet together with VyOS)
c) Modify vyos-build/Makefile to add a script four sources that sould be build locally from an upstream source before assembling the image?
Any other ideas are more then welcome ...