curl transaction failed on Section 7.4: Guided Exercise: Update Application Image and Settings

[AS16]

Hi. I'm trying Section 7.4: Guided Exercise: Update Application Image and Settings section 7.2 and I got curl failure once as a result of curl_loop.sh like below.

Hi!
Hi!
Hi!
curl: (7) Failed to connect to master01.ocp4.example.com port 30019: Connection refused
Hi! v1.1
Hi! v1.1
Hi! v1.1
Hi! v1.1
Hi!
Hi!
Hi! v1.1

As I confirmed like below guide section 5.5, "version" deployment has a readiness probe so it cannot be send http transaction to the pod who is not ready.

Please let me know why I got a failure of a curl command once?

5.5 Confirm that the version deployment includes a readiness probe. The probe performs an HTTP GET request on port 8080.

[student@workstation ~]$ oc get deployment version \
  -o jsonpath='{.spec.template.spec.containers[0].readinessProbe}' | jq . { "failureThreshold": 3, "httpGet": { "path": "/", "port": 8080, "scheme": "HTTP" }, "initialDelaySeconds": 3, "periodSeconds": 10, "successThreshold": 1, "timeoutSeconds": 1 }

[Wasim_Raja]

@AS16 If the pod was in the process of starting and hadn't yet passed its readiness probe, it would be temporarily Not Ready. During this time, curl might have hit a pod that wasn’t yet accepting traffic.