Managing pipeline errors

You can specify how to respond to errors in a pipeline globally, with an error policy, and locally, by overriding the policy on the node level. You can also create a custom error-handling response.

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Setting global error policy

The error policy sets the default behavior for errors in a pipeline. You can override this behavior for any node in the pipeline. To set the global error policy:

1. Click the Manage default settings icon on the toolbar.

2. Choose the default response to an error under Error policy:

   • Fail pipeline on error stops the flow and initiates a error-handling flow.

   • Continue pipeline on error tries to continue executing the pipeline.

     Note: Continue pipeline on error affects nodes that use the default error policy and does not affect node-specific error policies.

3. You can optionally create a custom error-handling response for a flow failure.

Specifying an error response

If you opt for Fail pipeline on error for either the global error policy or for a node-specific policy, you can further specify what happens on failure. For example, if you check Show icon on nodes that are linked to error-handling pipeline, an icon flags a node with an error to help debug the flow.

Specifying a node-specific error policy

You can override the default error policy for any node in the pipeline.

1. Click a node to open the configuration pane.

2. Check the option to Override default error policy with:

   • Fail pipeline on error

   • Continue pipeline on error

     Note: This option is only available for node types that.

Viewing all node policies

To view all node-specific error handling for a pipeline:

1. Click Manage default settings on the toolbar.
2. Click the view all node policies link under Error policy.

A list of all nodes in the pipeline show which nodes use the default policy, and which override the default policy. Click a node name to see the policy details. Use the view filter to show:

• All error policies: all nodes
• Default policy: all nodes that use the default policy
• Override default policy: all nodes that override the default policy
• Fail pipeline on error: all nodes that terminate the flow on error
• Continue pipeline on error: all nodes that try to continue the flow on error

Running the Fail on error flow

If you specify that the flow should fail on error, a secondary error handling flow starts when an error is encountered.

Adding a custom error response

If Create custom error handling response is checked on the default settings for error policy, you can add an error handling node to the canvas so you can configure a custom error response. The response will apply to all nodes configured to fail when an error occurs.

Notes on error handling

The error policy applies only to the run part of the component and problem. For example, for the Run DataStage Flow, the error policy only applies to problems with the DataStage job run. Other errors, such as a failure to create the DataStage job run, exit even if the error policy set to Continue on Error, but you can use the exception handler to catch those occurrences.

Parent topic: Creating a pipeline