Comment 8 for bug 1781699

To those waiting for a fix: I'm using a workaround by setting systemd to restart the service when it crashes. This works well for me:

$ cat /etc/systemd/system/isc-dhcp-server6.service.d/override.conf
[Service]
Restart=on-abort
RestartSec=1

Run systemctl daemon-reload after creating/changing the file.