Sometimes for debugging need to build accel-ppp with additional flags:

-DCMAKE_BUILD_TYPE=Debug - Include debug information to accel-pppd binary

-DCMAKE_C_FLAGS='-g -O0' - Enable optimization flags

-DMEMDEBUG=TRUE - Set this flag if you want to debug memleak

Allow create core dump files without size limiting, edit /etc/security/limits.conf and add

*  soft  core  unlimited

Or run ulimit -c unlimited for apply immediately

Edit /etc/sysctl.conf to define core dump file name and location, add

kernel.core_uses_pid = 1
kernel.core_pattern = /root/core-%e-%p

And apply sysctl -p

If accel-ppp runs as systemd service to allow create coredumps it is necessary to add DefaultLimitCORE=infinity to /etc/systemd/system.conf and run systemctl daemon-reexec to activate new params.

Recommended: to create a self-checking program with predefined mistake. Create test.c with the following content

int main() {
  *(char *)0 = 0;
  return 0;

Compile this program gcc test.c and run ./a.out

If core files appear in /root directory and in dmesg exist output a.out[xxxx]: segfault at ... then all done properly.

Run accel-ppp in GDB (GNU Debugger)

If you want to run accel-ppp in GDB, necessary disable logratation for accel-ppp log files.

gdb -ex=run  --args accel-pppd -c /etc/accel-ppp.conf -p /var/run/