Vanflow: Duplicate message delivery per distinct router path

[c-kruse]

As discussed in the Skupper Team g chat, I am observing repeated delivery of vanflow messages. This was uncovered by an unrelated skupper collector bug. Thanks for following along @ted-ross! I suspect this issue is in the router, but I didn't know where to start trying to reproduce it without the control plane.

To reproduce:

• Set up Skupper version 1.5.1 running in three namespaces a, b and c and link all three.

  
  skupper token create --namespace a --uses 2 token-a.yaml

skupper link create --namespace b token-a.yaml skupper token create --namespace b token-b.yaml

skupper link create --namespace c token-a.yaml skupper link create --namespace c token-b.yaml

* Deploy this rough draft vanflow logging utility to each namespace to tail the logs. [source](https://github.com/c-kruse/skupper/tree/vanflow-tool/cmd/vanflow-tool).

apiVersion: apps/v1 kind: Deployment metadata: name: vanflow-logging labels: app: vanflow-logging spec: replicas: 1 selector: matchLabels: app: vanflow-logging template: metadata: labels: app: vanflow-logging spec: containers:

• image: quay.io/ckruse/vanflow-tool:1.0-alpha3 imagePullPolicy: Always name: main securityContext: runAsNonRoot: true volumeMounts:
  • mountPath: /etc/messaging/ name: skupper-local-client args:
  • '-messaging-config=/etc/messaging/connect.json'
  • '-enable-flow-records=false'
  • 'log' volumes:
• name: skupper-local-client secret: defaultMode: 420 secretName: skupper-local-client

• Tail the logs of the vanflow logging utilities as you interact with the cluster. Messages originating in the A namespace are logged once from the A namespace but twice from the B and C namespaces.

[jiridanek]

This is probably a workaround for this?

• https://github.com/skupperproject/skupper/pull/1341

[c-kruse]

This is probably a workaround for this?

* [Fixes phantom process records observed in the console UI skupper#1341](https://github.com/skupperproject/skupper/pull/1341)

They are related @jiridanek - but I'd hesitate to call either a workaround. The flow collector should be idempotent (fix in skupper/pull/1341), and from what I understand vanflow messages should be delivered only once to each consumer with some reliability regardless of van topology (the topic brought up in this issue.)

[Karen-Schoener]

Hi, I'm interested in investigating this ticket. If there's any concern / issue with me investigating this ticket, please do not hesitate to let me know. Thanks, Karen