Starting replication on a replication set

You can select a replication set on which to start replicating tables from the source database by using the Db2 Q Replication API.

Before you begin

This task is done on the cluster host for the replication source. Ensure that you collect the following information before you run the API call:

  • The basic authorization token of the source on the cluster host.1
  • The host name of the replication source database.
  • The external port number of the replication source database.2
  • The replication set name (rsName)3
  • The consistency group name (cgName)
You need this information to run the needed Replication REST API calls.
1 You need to create a basic authorization token to run a cURL request. To create your token, run this command::
echo <source_db_username>:<source_db_password> | base64
2 You can retrieve the external port number of the replication source database by running the following command:
oc get svc | grep <db2_instance_id> | grep db2u-engn-svc | grep 50001 | sed 's/.*50001://' | sed 's/\/TCP.*//')
3 You can find the replication set name (rsName) and consistency group name (cgName) by running the following command:
curl --insecure -X GET --header 'Content-Type: application/json' --header 'Accept: application/json' --header 'Authorization: Basic <your_authorization_token>' 
'https://<source_hostname>:<source_rest_port>/dr/v1/replicationset'

About this task

This API call triggers a task to start a replication set. A replication set is identified by the rsName and cgName values. After a replication set is started, source tables begin to replicate.

Procedure

  1. Start replication on a replication set: 
    curl --insecure -X POST --header 'Content-Type: application/json' --header 'Accept: application/json' --header 'Authorization: Basic <your_authorization_token>'  
'https://<source_hostname>:<source_rest_port>/dr/v1/replicationset/<replication_set_name>/<consistency_group_name>/start'
    This API call returns a job number (id).
    {
  "id": <job_number>,
  "url": "https://<source_hostname>:<source_rest_external_port>/dr/v1/target/progress/<job_number>"
}
  2. Include the job number in the following API call to check the progress of the start replication operation: 
    curl --insecure -X GET --header 'Accept: application/json' --header 'Authorization: Basic <your_authorization_token>' 
'https://<source_hostname>:<source_rest_port>/dr/v1/replicationset/progress/<job_id>'

Results

The start replication request is complete when a response message that contains executionState=COMPLETED and overallJobResult=PASS is returned. Until these values are returned, examine the error code, message, and resolution in the response.
The following table lists the possible HTTP status codes and response messages for the start replication request. It also includes sample code to show the response syntax.
HTTP Status Code Reason Response Model
200 Details for replication The user request returns a job (id) and URL as the API call starts (sample value):

{
  "id": 11,
  "url": "https://dr-source1.ibm.com:31023/dr/v1/replicationset/progress/11"
}
The user request returns a successful response for the completion of the API call (sample value):


{
  "id": 11,
  "url": "https://api.dr-source1.ibm.com:31023/dr/v1/replicationset/progress/11",
  "executionState": "COMPLETED",
  "overallJobResult": "PASS",
  "jobStatusList": [
    {
      "jobKey": "startRepCg",
      "jobDescription": "Start replication for consistency group.",
      "execState": "COMPLETED",
      "jobResult": "PASS",
      "values": [],
      "errors": []
    }
  ]
}
4xx Client request error The user request was not fulfilled due to malformed request syntax or other client issues:
{
  "errorCode": "string",
  "errorMessage": "string",
  "errorResolution": "string"
}
5xx Server error The user request appeared valid, but was not fulfilled due to an issue with the server:
{
  "errorCode": "string",
  "errorMessage": "string",
  "errorResolution": "string"
}

Example

The following example shows the command syntax for starting replication on the replication set RS_MPP_2. See step 1:
curl --insecure -X POST --header 'Content-Type: application/json' --header 'Accept: application/json' --header 'Authorization: Basic ZHNhZG06MDNRVWlMczFhcmoxb3ky' 
'https://dr-source1.ibm.com:31023/dr/v1/replicationset/RS_MPP_2/RSMPP20001/start'
The following example shows the command syntax for checking the status of the start replication operation with the job number 11. See step 2:
curl --insecure -X GET --header 'Content-Type: application/json' --header 'Accept: application/json' --header 'Authorization: Basic ZHNhZG06MDNRVWlMczFhcmoxb3ky'
'https://dr-source1.ibm.com:31023/dr/v1/replicationset/progress/11'