ipvsadm: allow tunneling with gre encapsulation

Add support for real server tunnels with GRE encapsulation:
--tun-type gre [--tun-nocsum|--tun-csum]

Co-developed-by: Vadim Fedorenko <vfedorenko@yandex-team.ru>
Signed-off-by: Vadim Fedorenko <vfedorenko@yandex-team.ru>
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
3 files changed