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are hypervisors mandatory?

asked 2017-06-30 05:15:28 -0500

Hyder gravatar image

I'm very new to openstack and I have installed packstack All-in-One on Centos 7. To launch an instance is it necessary to have hypervisors? if yes then how to configure them if no then why I'm not able to launch an instance. when I launch an instance it says 'No valid host was found' what does it mean?

Thank you

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answered 2017-06-30 18:10:39 -0500

You can use physical machines as instances, but I don't know whether Packstack supports that, and it's probably not your goal. If your instances are virtual machines, you need a hypervisor; OpenStack can use KVM, qemu, Hyper-V, Xen and a few more. Packstack deploys qemu or KVM by default.

"No valid host found" means that no compute host is suitable for running the instance you want to launch. For example, there may not be enough capacity, such as storage or RAM, or no host with the correct CPU architecture. You could inspect the nova scheduler log to get clarity, or check your compute capacities with the openstack hypervisor show command.

Perhaps you are using the wrong flavor?

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Could you please advise how to fix Nova scheduler issue? This service returns exit code 1 and can't start. That is why openstack install is failed [nova-db-sync]. I have searched all the journalctl and var/log/messages but managed to find only error of Nova scheduler. Have no ideas of its rootcause.

kostyanius gravatar imagekostyanius ( 2017-07-30 14:04:31 -0500 )edit

I suggest you open another question and include the error message(s).

Bernd Bausch gravatar imageBernd Bausch ( 2017-08-03 09:52:33 -0500 )edit

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Asked: 2017-06-30 05:15:28 -0500

Seen: 66 times

Last updated: Jun 30 '17