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[BUG/Question] HyperV Entropy doesn't appear to be consumed through new agent system

See original GitHub issue

Describe the bug Per the README, Consume Hyper-V entropy for /dev/random this appears to only be done through the waagent2.0 script. The waagent script will only run the waagent2.0 script when __name__ == 'waagent'.

https://github.com/Azure/WALinuxAgent/blob/4c7c8925cb2a4109e9e7ba05800fe53f0b93596e/bin/waagent2.0#L5680-L5684

Unless I’m missing some other way that HyperV Entropy is being consumed especially since the HyperV VMBUS doesn’t invoke the LRNG interrupt handler in the Linux kernel.

Issue Analytics

  • State:closed
  • Created 4 years ago
  • Reactions:2
  • Comments:5 (3 by maintainers)

github_iconTop GitHub Comments

1reaction
narrietacommented, Aug 17, 2020

@kovacs-andras @colemickens The Agent was rewritten in late 2014 and the new version did not include this code, but the documentation was not updated. I have updated the documentation. The VM Agent is not the best place to do this; the place where it was done in the code may be too late for components that need this during boot. Also, the agent can be disabled/deleted. We are not planning on adding this functionality back.

1reaction
colemickenscommented, Jul 16, 2020

So is it not necessary to do this anymore in Azure VMs or… why was this functionality removed?

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