Failure when processing extension 'vmssCSE'. Exit status=50

[arodriguezdlc]

Describe the bug

We have problems to deploy with aks-engine because some agent pools can't access to internet during bootstrapping. This is the error:

Error: Code="DeploymentFailed" Message="At least one resource deployment operation failed. Please list deployment operations for details. Please see https://aka.ms/arm-debug for usage details." Details=[{"code":"Conflict","message":"{\r\n \"status\": \"Failed\",\r\n \"error\": {\r\n \"code\": \"ResourceDeploymentFailure\",\r\n \"message\": \"The resource operation completed with terminal provisioning state 'Failed'.\",\r\n \"details\": [\r\n {\r\n \"code\": \"VMExtensionProvisioningError\",\r\n \"message\": \"VM has reported a failure when processing extension 'vmssCSE'. Error message: \\\"Enable failed: failed to execute command: command terminated with exit status=50\\n[stdout]\\nThu Oct 24 14:18:01 UTC 2019,k8s-genm-21270049-vmss000000\\n\\n[stderr]\\n\\\".\"\r\n }\r\n ]\r\n }\r\n}"}]

Checking documentation and code, I have seen that node executes some nc command to check connectivity with some docker registries. If these commands fail, error 50 is returned. Also, I have connected manually to a failed node and it had connectivity issues.

I don't know if it's an aks-engine issue or an Azure cloud issue. Are you having similar issues?

Steps To Reproduce Execute aks-engine deploy command.

Expected behavior Correct deployment.

AKS Engine version 0.42.2

Kubernetes version 1.14.7

Additional context

[ericsuhong]

We are also occasionally experiencing this issue as well. But usually retry succeeds, but annoying sometimes.

[nidiculageorge]

We have disabled outbound connectivity to internet in NSG for the aks agent pool. Seems this occurred because of that