seqdiag {
    node_width = 90;
    edge_length = 130;

    Client -> "tacker-server"
      [label = "POST /vnflcm/v2/vnf_lcm_op_occs/{vnfLcmOpOccId}/rollback"];
    Client <-- "tacker-server" [label = "Response 202 Accepted"];
    "tacker-server" ->> "tacker-conductor"
      [label = "trigger asynchronous task"];
    "tacker-conductor" -> "tacker-database"
      [label = "mark operation as ROLLING_BACK"];
    "tacker-conductor" <-- "tacker-database"
    "tacker-conductor" ->> "tacker-conductor"
      [label = "execute notification process"];
    Client <- "tacker-conductor"
     [label = "POST {callback URI} (ROLLING_BACK)"];
    Client --> "tacker-conductor" [label = "Response: 204 No Content"];
    "tacker-conductor" -> "VnfLcmDriver" [label = "execute LCM operation"];
    "VnfLcmDriver" ->> "VnfLcmDriver" [label = "recreated stack parameters using instantiatedVnfInfo"];
    "VnfLcmDriver" -> "openstackDriver" [label = "execute openstackDriver"];
    "openstackDriver" -> "heat" [label = "update stack (PATCH /v1/{tenant_id}/stacks/{stack_name}/{stack_id})"];
    "openstackDriver" <-- "heat" [label = ""];
    "VnfLcmDriver" <-- "openstackDriver" [label = ""];
    "tacker-conductor" <-- "VnfLcmDriver" [label = ""];
    "tacker-conductor" -> "tacker-database"
      [label = "mark operation as ROLLED_BACK"];
    "tacker-conductor" <-- "tacker-database"
    "tacker-conductor" ->> "tacker-conductor"
      [label = "execute notification process"];
    Client <- "tacker-conductor"
      [label = "POST {callback URI} (ROLLED_BACK or FAILED_TEMP)"];
    Client --> "tacker-conductor" [label = "Response: 204 No Content"];
  }