@classmethod
def add_del_shared_mcast_dst_load(cls, is_add):
    '\n        add or del tunnels sharing the same mcast dst\n        to test gtpu ref_count mechanism\n        '
    n_shared_dst_tunnels = 20
    teid_start = 1000
    teid_end = (teid_start + n_shared_dst_tunnels)
    for teid in range(teid_start, teid_end):
        r = cls.vapi.gtpu_add_del_tunnel(decap_next_index=4294967295, src_address=cls.pg0.local_ip4, dst_address=cls.mcast_ip4, mcast_sw_if_index=1, teid=teid, is_add=is_add)
        if (r.sw_if_index == 4294967295):
            raise ValueError('bad sw_if_index: ~0')
add or del tunnels sharing the same mcast dst
to test gtpu ref_count mechanism
@classmethod
def add_del_shared_mcast_dst_load(cls, is_add):
    '\n        add or del tunnels sharing the same mcast dst\n        to test gtpu ref_count mechanism\n        '
    n_shared_dst_tunnels = 20
    teid_start = 1000
    teid_end = (teid_start + n_shared_dst_tunnels)
    for teid in range(teid_start, teid_end):
        r = cls.vapi.gtpu_add_del_tunnel(decap_next_index=4294967295, src_address=cls.pg0.local_ip4, dst_address=cls.mcast_ip4, mcast_sw_if_index=1, teid=teid, is_add=is_add)
        if (r.sw_if_index == 4294967295):
            raise ValueError('bad sw_if_index: ~0')