Configuring the PowerConnect Cloud Agent Retries

Overview

The PowerConnect Cloud agent can be configured to retry on both the collection of data (Inputs) and the sending of data (Outputs)

Simple Input Retries

During the collection of data from the various SAP APIs its possible that the API endpoint may experience an issue or that there may be a network problem that stops the PowerConnect Cloud Agent from communicating with the API temporarily. By default upon recieving a retryable status code or error from an API e.g. 500 or SocketException the HTTP call will be retried automatically. The HTTP call will be retried 3 times, waiting 3 seconds between each call before giving up.

These defaults can be overridden by:

• Logging into the PowerConnect Cloud UI

• Clicking on the Configuration Tab

• Scroll down to the HTTP Configuration for Inputs section
  

  

• Here we can set the default Connection Timeout, number of retries and the retry interval that applies to all Inputs

This configuration will cater for occasional network glitches etc. however where more advanced retry logic is required this can be configured on a per Input basis as detailed below.

Advanced Input Retries

To configure advanced retries for an Input:

• Login to the PowerConnect Cloud UI

• Click on the Inputs Tab

• Click the Edit button on the Input you wish to configure advanced retries for

• Click on the Advanced Tab
  

  

• Check the Retry if error occurs checkbox

• Set the number of times to retry

• Set the Initial backoff interval in seconds
  

When the advanced retries are enabled the following rules apply

• The global retry settings apply to the individual HTTP calls as part of the Input making calls to the SAP APIs to retrieve data

• If these fail (e.g. retry 3 times at 3 second intervals) the advanced retry configuration then applies when enabled

• Any data successfully collected before the failure will be discarded so as not to produce partial results

• The Input job will be parked for the “Initial backoff interval in seconds” value e.g 60 seconds

• After this period has elaspsed the Input job will be retried

• If it fails again the backoff is exponential so the Input job will be parked for twice the backoff interval value (e.g. 120 seconds) and so on until the retries are exhausted or the Input job succeeds

• Retry jobs are cluster aware so if a node is lost whilst the retry job is parked waiting to be retried it will processed by another node

• If Checkpointing is enabled for the input then no further jobs will be run for that Input whilst the retry is running

• If Checkpointing is enabled with the Split Job option then only the task that failed will be retried not the entire job. When the Input next runs it will use the last checkpoint value that succeeded so no data will be lost

The advanced retry option is useful where data integrity is important e.g. CPI Messages

Output Retries

To configure advanced retries for an Output:

• Login to the PowerConnect Cloud UI

• Click on the Ouputs Tab

• Click Edit on the Output you wish to configure retries for

  

• Check the Retry send if error occurs checkbox

• Enter the Number of times to retry

• Enter the Backoff interval in seconds

• Click Save