Software AG Products 10.11 | Upgrade and Migration in API Gateway | Upgrading API Gateway in Zero Downtime | Upgrading Major Versions in Zero Downtime | Put the old API Gateway instances in quiesce mode for design time
 
Put the old API Gateway instances in quiesce mode for design time
You must perform this operation in the old API Gateway instances. For a cluster, you must do this at each node as quiesce mode is enabled at the instance level.
API Gateway data in the API Data Store is migrated in two phases. In the first phase, only the design time data like APIs, applications, and policies are migrated. The runtime data like audit logs, transaction logs, performance metrics, and so on are migrated in the next phase, that is, after the runtime transactions to the old instances are stopped. This is performed after the new instance is up and running with the new data and runtime traffic is allowed to it.
Before migrating design time data in the first phase, all the updates to them through UI and REST APIs must be blocked. This can be achieved by using the quiesce mode capability available in API Gateway.
You can use the following request to enable quiesce mode for design time in the old API Gateway instance.
PUT /rest/apigateway/quiescemode

{
"enable": true,
"block": "designtime"
}
If the invocation is successful, the request returns a 200 OK message.
Now, all the design time invocations to the old instance are blocked and API Gateway returns 503 message to the client. Only the following requests are allowed:
*All GET requests
*/rest/apigateway/quiescemode
*/rest/apigateway/search
*/rest/facade/apigateway/searchApis
When the quiesce mode for design time is complete, API Gateway sends out a notification with the result details through registered webhooks. You can also run the following request to check the status of the operation.
GET rest/apigateway/quiescemode
A success status message implies that quiesce mode for design time is completed.
If the quiesce mode for design time API call fails with an error or the status returned with a failure, you must stop execution of the next steps. Disable the quiesce mode for design time in all the nodes and bring them back to normal state. If the error persists, contact Software AG support team for help with all the relevant logs for further analysis.