tacker/doc/source/user/etsi_vnf_error_handling.rst

ETSI NFV-SOL VNF error-handling

This document describes how to error-handling VNF in Tacker.

Note

Rollback and retry are NOT supported in version 2 vnflcm APIs in Xena yet. So, You should recover it by yourself instead if instantiation is failed via v2 API. The recovering process may include deleting a stack via HEAT API.

Prerequisites

The following packages should be installed:

• tacker
• python-tackerclient

A default VIM should be registered according to ../cli/cli-legacy-vim.

The VNF Package(sample_vnf_pkg.zip) used below is prepared by referring to ./vnf-package.

Execute up to "Instantiate VNF" in the procedure of ./etsi_vnf_deployment_as_vm_with_tosca. In other words, the procedure after "Terminate VNF" is not executed.

VNF Error-handling Procedures

As mentioned in Prerequisites, the VNF must be created before performing error-handling.

Details of CLI commands are described in ../cli/cli-etsi-vnflcm.

There are some operations to error-handling VNF.

• Rollback VNF lifecycle management operation
• Fail VNF lifecycle management operation
• Retry VNF lifecycle management operation

In order to execute error-handling, it is necessary to specify VNF_LCM_OP_OCC_ID, which is the ID for the target LCM operation. First, the method of specifying the ID will be described.

Identify VNF_LCM_OP_OCC_ID

To identify the VNF_LCM_OP_OCC_ID, you can get with the following ways.

• to check with CLI
• to check with notification API body

You can choose both ways.

This case uses openstack CLI:

Details of CLI commands are described in ../cli/cli-etsi-vnflcm.

Before checking the "VNF_LCM_OP_OCC_ID", you should get VNF_INSTANCE_ID first.

$ openstack vnflcm op list

Result:

+--------------------------------------+-----------------+--------------------------------------+-----------------+
| ID                                   | Operation State | VNF Instance ID                      | Operation       |
+--------------------------------------+-----------------+--------------------------------------+-----------------+
| 304538dd-d754-4661-9f17-5496dab9693d | FAILED_TEMP     | 3aa5c054-c162-4d5e-9808-0bc30f92a4c7 | INSTANTIATE     |
+--------------------------------------+-----------------+--------------------------------------+-----------------+

For this case, check notification API body:

In checking with Notification API, you should execute the following steps:

• Create a new subscription
• Execute LCM operations, such as 'Creates a new VNF instance resource'.

The procedure for executing the API using the curl command is shown below.

First, the method of generating Keystone-tokens will be described. See Keystone API reference. for details on Keystone APIs. For <username> and <password>, <project_name>, set values according to your environment.

Prepare get_token.json file to get token:

{
  "auth": {
    "identity": {
      "methods": [
        "password"
      ],
      "password": {
        "user": {
          "name": "<username>",
          "password": "<password>",
          "domain": {
            "name": "Default"
          }
        }
      }
    },
    "scope": {
      "project": {
        "name": "<project_name>",
        "domain": {
          "name": "Default"
        }
      }
    }
  }
}

Get token:

$ curl -i -X POST -H "Content-Type: application/json" -d @./get_token.json  "$OS_AUTH_URL/v3/auth/tokens"

Result:

HTTP/1.1 201 CREATED
Date: Tue, 17 Nov 2020 08:01:44 GMT
Server: Apache/2.4.41 (Ubuntu)
Content-Type: application/json
Content-Length: 7187
X-Subject-Token: gAAAAABfs4No8WVYIPagnJvnnImNHq_918oLgOiJwSXqXGJKfv_FEcgfeZajIl0NCk7Pr6YMn1Sa96ZhOnWioKGrOxBSEGVxgYqBFx3bFfKAHVmzgoEaN6zfHZvbm1QJgoeg1QV5i-VjfeeQRWZptYqd3yWMLzrWSfVBER9pL-nRi0CvMXJM0yE
Vary: X-Auth-Token
x-openstack-request-id: req-6b19a1ee-0eb0-4aa8-97e7-c54d750c9b64
Connection: close
...snip response-body...

Set the value of X-Subject-Token included in the above result to the environment variable $OS_AUTH_TOKEN.

$ export OS_AUTH_TOKEN="gAAAAABfs4No8WVYIPagnJvnnImNHq_918oLgOiJwSXqXGJKfv_FEcgfeZajIl0NCk7Pr6YMn1Sa96ZhOnWioKGrOxBSEGVxgYqBFx3bFfKAHVmzgoEaN6zfHZvbm1QJgoeg1QV5i-VjfeeQRWZptYqd3yWMLzrWSfVBER9pL-nRi0CvMXJM0yE"

Create subscription:

$ curl -g -i -X POST http://127.0.0.1:9890/vnflcm/v1/subscriptions \
  -H "Accept: application/json" \
  -H "Content-Type: application/json" \
  -H "X-Auth-Token: $OS_AUTH_TOKEN" \
  -d '{"callbackUri": "http://127.0.0.1/"}'

Result:

HTTP/1.1 201 Created
Content-Length: 199
Location: http://localhost:9890//vnflcm/v1/subscriptions/5bd3b81d-a6e9-45e7-922e-adc26328322d
Content-Type: application/json
X-Openstack-Request-Id: req-5f98782d-ca47-4144-a413-bd9641302f77
Date: Mon, 21 Dec 2020 08:21:47 GMT

{"id": "5bd3b81d-a6e9-45e7-922e-adc26328322d", "callbackUri": "http://127.0.0.1/", "_links": {"self": {"href": "http://localhost:9890//vnflcm/v1/subscriptions/5bd3b81d-a6e9-45e7-922e-adc26328322d"}}}

Show subscription:

$ curl -g -i -X GET http://127.0.0.1:9890/vnflcm/v1/subscriptions/{subscriptionId} \
  -H "Accept: application/json" \
  -H "X-Auth-Token: $OS_AUTH_TOKEN"

Result:

HTTP/1.1 200 OK
Content-Length: 213
Content-Type: application/json
X-Openstack-Request-Id: req-2d7503dc-1f75-40de-9d75-7c01180aee89
Date: Mon, 21 Dec 2020 08:22:59 GMT

{"id": "5bd3b81d-a6e9-45e7-922e-adc26328322d", "filter": {}, "callbackUri": "http://127.0.0.1/", "_links": {"self": {"href": "http://localhost:9890//vnflcm/v1/subscriptions/5bd3b81d-a6e9-45e7-922e-adc26328322d"}}}

Show VNF LCM operation occurrence:

$ curl -g -i -X GET http://127.0.0.1:9890/vnflcm/v1/vnf_lcm_op_occs/{vnfLcmOpOccId} \
  -H "Accept: application/json" \
  -H "X-Auth-Token: $OS_AUTH_TOKEN"

Result:

HTTP/1.1 200 OK
Content-Length: 3082
Content-Type: application/json
X-Openstack-Request-Id: req-d0720ffc-e7ee-4ee2-af61-a9a4a91c67cb
Date: Mon, 21 Dec 2020 08:30:25 GMT

{"id": "e3dc7530-e699-46ed-b65e-32911af1e414", "operationState": "FAILED_TEMP", "stateEnteredTime": "2020-12-21 06:52:06+00:00",
...snip response-body...

Error-handling can be executed only when operationState is FAILED_TMP.

With the above LCM operation trigger, 'Notification' is sent to the callbackUri set in 'Create a new subscription'.

vnfLcmOpOccId included in this 'Notification' corresponds to VNF_LCM_OP_OCC_ID.

See Tacker API reference. for details on the APIs used here.

Rollback VNF LCM Operation

This manual describes the following operations as use cases for rollback operations.

• "Instantiate VNF" fails
• Rollback VNF lifecycle management operation
• Delete VNF

As shown below, if "Instantiate VNF" fails, "Delete VNF" cannot be executed without executing "Rollback VNF lifecycle management operation".

$ openstack vnflcm delete VNF_INSTANCE_ID

Result:

Failed to delete vnf instance with ID '3aa5c054-c162-4d5e-9808-0bc30f92a4c7': Vnf 3aa5c054-c162-4d5e-9808-0bc30f92a4c7 in status ERROR. Cannot delete while the vnf is in this state.

Therefore, "Rollback VNF lifecycle management operation" with the following CLI command.

$ openstack vnflcm op rollback VNF_LCM_OP_OCC_ID

Result:

Rollback request for LCM operation 304538dd-d754-4661-9f17-5496dab9693d has been accepted

If "Rollback VNF lifecycle management operation" is successful, then "Delete VNF" is also successful.

$ openstack vnflcm delete VNF_INSTANCE_ID

Result:

Vnf instance '3aa5c054-c162-4d5e-9808-0bc30f92a4c7' deleted successfully

Fail VNF LCM Operation

This manual describes the following operations as use cases for fail operations.

• "Instantiate VNF" fails
• Fail VNF lifecycle management operation
• Delete VNF

As shown below, if "Instantiate VNF" fails, "Delete VNF" cannot be executed after executing "Fail VNF lifecycle management operation".

$ openstack vnflcm delete VNF_INSTANCE_ID

Result:

Failed to delete vnf instance with ID '3aa5c054-c162-4d5e-9808-0bc30f92a4c7': Vnf 3aa5c054-c162-4d5e-9808-0bc30f92a4c7 in status ERROR. Cannot delete while the vnf is in this state.

Therefore, "Fail VNF lifecycle management operation" with the following CLI command.

$ openstack vnflcm op fail VNF_LCM_OP_OCC_ID

Result:

Fail request for LCM operation 304538dd-d754-4661-9f17-5496dab9693d has been accepted

If "Fail VNF lifecycle management operation" is successful, then "Delete VNF" is also successful.

$ openstack vnflcm delete VNF_INSTANCE_ID

Result:

Vnf instance '3aa5c054-c162-4d5e-9808-0bc30f92a4c7' deleted successfully

Retry VNF LCM Operation

This manual describes the following operations as use cases for retry operations.

• "Instantiate VNF" fails
• Retry VNF lifecycle management operation

As shown below, if "Instantiate VNF" fails, If you want re-execute previous(failed) operation , you execute "Retry" operation.

Therefore, "Retry VNF lifecycle management operation" with the following CLI command.

$ openstack vnflcm op retry VNF_LCM_OP_OCC_ID

Result:

Retry request for LCM operation 304538dd-d754-4661-9f17-5496dab9693d has been accepted

If "Retry VNF lifecycle management operation" is successful, then another LCM can be operational.