seqdiag {
    node_width = 80;
    edge_length = 100;

    "Client"
    "Tacker-server"
    "Tacker-conductor"
    "VnfLcmDriver"
    "MgmtDriver"
    "TackerDB"
    "VIM(Kubernetes)"

    Client -> "Tacker-server"
      [label = "1. PATCH /vnflcm/v1/vnf_instances/{vnfInstanceId}"];
    Client <-- "Tacker-server"
      [label = "Response 202 Accepted"];
    "Tacker-server" -> "Tacker-conductor"
      [label = ""];
    "Tacker-conductor" -> "VnfLcmDriver"
      [label = "2. modify_vnf"];
    "VnfLcmDriver" -> "MgmtDriver"
      [label = "3. modify_start"];
    "VnfLcmDriver" <-- "MgmtDriver"
      [label = ""];
    "VnfLcmDriver" -> "TackerDB"
      [label = "4. Update vnfdid"];
    "VnfLcmDriver" <-- "TackerDB"
      [label = ""];
    "VnfLcmDriver" -> "MgmtDriver"
      [label = "5. modify_end"];
    "MgmtDriver" -> "VIM(Kubernetes)"
      [label = "5-1. get information of ConfigMap and Secret"];
    "MgmtDriver" <-- "VIM(Kubernetes)"
      [label = ""];
    "MgmtDriver" -> "MgmtDriver"
      [label = "5-2. select ConfigMap and Secret to replace"];
    "MgmtDriver" -> "VIM(Kubernetes)"
      [label = "5-3. replace config"];
    "MgmtDriver" <-- "VIM(Kubernetes)"
      [label = ""];
    "MgmtDriver" -> "TackerDB"
      [label = "5-4. select Pod that uses the old ConfigMap or Secret"];
    "MgmtDriver" <-- "TackerDB"
      [label = ""];
    "MgmtDriver" -> "VIM(Kubernetes)"
      [label = "5-5. get information of Pod"];
    "MgmtDriver" <-- "VIM(Kubernetes)"
      [label = ""];
    "MgmtDriver" -> "MgmtDriver"
      [label = "5-6. select Pod whose image has changed"];
    "MgmtDriver" -> "VIM(Kubernetes)"
      [label = "5-7. replace Pod"];
    "MgmtDriver" <-- "VIM(Kubernetes)"
      [label = ""];
    "VnfLcmDriver" <-- "MgmtDriver"
      [label = ""];
    "VnfLcmDriver" -> "TackerDB"
      [label = "6. Update resourceid"];
    "VnfLcmDriver" <-- "TackerDB"
      [label = ""];
    "Tacker-conductor" <-- "VnfLcmDriver"
      [label = ""];
  }