add node label selector to Terminator #625
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| Expect(drainedNodes).To(BeEmpty()) | ||
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| It("does not delete the message from the SQS queue", func() { |
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How long do messages stay on the SQS queue? It seems like there could be a failure mode where NTH spends all its time re-processing messages on the queue (because, e.g., the labels didn't match) and isn't able to respond to new messages in time for k8s to gracefully handle a node termination. That's probably uncommon, but it is basically what mechanical-fish described in #494.
Is that a concern with this way of handling node labels? It seems like the philosophy of the terminator is "I only respond to requests that match my parameters; anything else I will leave for someone else to handle". So it may not be possible to prevent that situation. Curious what your thoughts are.
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Queues have a message retention period setting. A dead-letter queue can also be configured.
Leaving the message in the queue gives another Terminator instance a chance to match and handle it.
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Issue #, if available:
#556 Initial NTH v2 design proposal
Description of changes:
Add
matchLabelsproperty to the Terminator spec.NTH will take no action when an SQS message targets a node that does not have the requisite labels and values.
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