I have come across this repo and struggle to understand these steps.
I believe this is to enable the Netfilter conntrack events, but I'm not sure.
What do I have to run to get these prompts?
-------------------------------------------------------- 2. The minimum requirements for the kernel configuration -------------------------------------------------------- Kernel version >= 4.4 Networking support ---> Networking options ---> [*] Network packet filtering framework (Netfilter) ---> Core Netfilter Configuration ---> Netfilter connection tracking support (M/Y) Number of custom extend (1) (if patched kernel) "connlabel" match support (M) Check your kernel configuration file. For non-patched kernel there should be: CONFIG_NF_CONNTRACK=m or y CONFIG_NF_CONNTRACK_LABELS=y CONFIG_NETFILTER_XT_MATCH_CONNLABEL=m CONFIG_UNUSED_SYMBOLS=y For patched kernel there should be: CONFIG_NF_CONNTRACK=m or y CONFIG_NF_CONNTRACK_CUSTOM=1 CONFIG_UNUSED_SYMBOLS=y UPDATE:
I installed apt install conntrack as suggested. I'm not sure if the kernel is correctly setup, which is my main question here.
But moving on to the third section, compiling it fails too. I wonder if this is an issue on the repo or the minimum requirements aren't met.
admin@de-vpn-1:~/dd-wrt/src/router/ndpi-netfilter$ ./autogen.sh autoreconf: Entering directory `.' autoreconf: configure.ac: not using Gettext autoreconf: running: aclocal --force -I m4 autoreconf: configure.ac: tracing autoreconf: running: libtoolize --copy --force libtoolize: putting auxiliary files in AC_CONFIG_AUX_DIR, '.'. libtoolize: copying file './ltmain.sh' libtoolize: putting macros in AC_CONFIG_MACRO_DIRS, 'm4'. libtoolize: copying file 'm4/libtool.m4' libtoolize: copying file 'm4/ltoptions.m4' libtoolize: copying file 'm4/ltsugar.m4' libtoolize: copying file 'm4/ltversion.m4' libtoolize: copying file 'm4/lt~obsolete.m4' autoreconf: running: /usr/bin/autoconf --force autoreconf: running: /usr/bin/autoheader --force autoreconf: running: automake --add-missing --copy --force-missing configure.ac:54: installing './compile' configure.ac:6: installing './missing' configure.ac:336: error: required file 'example/Makefile.in' not found configure.ac:336: error: required file 'tests/Makefile.in' not found configure.ac:336: error: required file 'tests/unit/Makefile.in' not found configure.ac:336: error: required file 'tests/performance/Makefile.in' not found configure.ac:336: error: required file 'tests/dga/Makefile.in' not found configure.ac:336: error: required file 'rrdtool/Makefile.in' not found configure.ac:336: error: required file 'influxdb/Makefile.in' not found configure.ac:337: error: required file 'tests/do.sh.in' not found Makefile.am:2: error: required directory ./tests does not exist 
apt, I don't think there's a need to compile a custom version unless you have a clear and specific need for the custom version. Perhaps your question is more about "How do I configure and use netfilter with connection tracking" than "How do I compile the software from that github repo?"