@classmethod
    def clear_routers(cls):
        for router in cls.routers:
            try:
                (cls.client.remove_router_interface_with_subnet_id(
                 router['id'], cls.subnets[0]['id']))
            except Exception, e:
                LOG.info('Exception raised in detaching router: %s', router['id'])
                LOG.exception(e)
        for router in cls.routers:
                cls.client.delete_router(router['id'])

    @classmethod
    def tearDownClass(cls):
        for ipsecpolicy in cls.ipsecpolicies:
            cls.client.delete_ipsec_policy(ipsecpolicy['id'])
        for ikepolicy in cls.ikepolicies:
            cls.client.delete_ike_policy(ikepolicy['id'])
        for vpnservice in cls.vpnservices:
            cls.client.delete_vpn_service(vpnservice['id'])
        cls.clear_routers()