[nova-conductor] NoValidHost: No valid host was found.

asked 2019-08-29 11:26:03 -0500

dabovard gravatar image

Hello everyone, I am new to OpenStack and still learning the ropes (fairly slowly). I have managed to get a minimal two node architecture which comprises a controller node and a compute node. On this architecture I have set up a network with 3 instances on it. I have set up a cirrOS image, a Windows XP image, and a Windows 7 image. It took me awhile, but I got connectivity between the instances and they can ping each other.

My boss wants me to put a few other operating systems on the network as well for testing purposes, but I have encountered an error which has stopped me in my tracks.

I can create a 4th image if it is a tiny cirrOS image that has 1GB of disk space. When attempting to create a 4th instance that has 20G of disk space, I encounter an error in the nova-conductor log. The error says: "NoValidHost: No valid host was found. There are not enough hosts available."

Upon looking at similar errors here on ask openstack, it seems to be a resource related issue. I am inclined to believe that too because instance creation works for small instances, but as soon as I crank up the disk space I get this error.

My issue is that the CPU time, Memory Usage, and Disk space on both of my nodes are all under 50% usage. Does anybody have any idea what the issue could be when it clearly seems like a resource issue? Perhaps it is some configuration issue internal to nova because both nodes have plenty of resources available. Any information that could shed some light on the situation would be greatly appreciated. Thanks!!!

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What counts is not the overall free storage space, but the space dedicated to instance storage or volumes. To say more, I would have to know how your cloud was deployed and configured, and whether your instances use ephemeral storage or volumes.

Bernd Bausch gravatar imageBernd Bausch ( 2019-08-29 17:17:46 -0500 )edit