Newton Launching a new Instance. - "No valid host was found. There are not enough hosts available." [closed]

asked 2017-04-06 10:21:32 -0600

updated 2017-04-07 16:46:12 -0600

I am running Ubuntu 16.04 and OpenStack Newton. I have one server running as controller node.

When I am trying to launch new instance using CLI or horizon dashboard. An error occurs

No valid host was found. There are not enough hosts available.

I was trying to change ram and vCPU allocation ratio but it doesn't seems like it have any effect on it.

I think this might be something wrong with my Nova configuration. Here are my logs:

Error from horizon dashboard

This is what I see when I am issuing command nova hypervisor-statsIt seems like it does not see any available resources. Which I should have enough for at least small flavor instance.

However my nova quota-showproves I have plenty of resources to use

Here is my nova.conf file and errors from nova-conductor.log

Also nova-scheduler.log file

This is also propably realted to the issue when I am accessing "Admin/System/All Hypervisors" via horizon dashboard the list is empty. I am not sure if I should see anything there?


This is what probably causing an issue no hypervisors available in Nova, still I do not know how to solve this problem.

nova hypervisor-list

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Closed for the following reason the question is answered, right answer was accepted by student
close date 2017-04-07 17:18:41.920900



Can you check the nova-scheduler log?

kuro gravatar imagekuro ( 2017-04-06 11:30:41 -0600 )edit

Here is my nova-scheduler.log file:

and errors from nova-conductor.log

student gravatar imagestudent ( 2017-04-06 12:45:43 -0600 )edit

4 answers

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answered 2017-04-07 08:50:11 -0600

luowei gravatar image

updated 2017-04-07 08:58:21 -0600

First check nova.conf on controller and computes for lingering mismatched region names (i.e. "RegionOne" everywhere, not "openstacl" or "regionOne").

I don't think it is linked to allocation ratio, but I found I needed to explicitly provide the scheduler filters when specifying a ratio in nova.conf:

scheduler_default_filters =  ComputeFilter, CoreFilter, RamFilter, SameHostFilter
ram_allocation_ratio = 1.5
cpu_allocation_ratio = 30.0
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You are right it is not allocation ratio it is no hypervisors available. There is nothing in the nova hypervisor list ->

But I do not know what can cause an issue

student gravatar imagestudent ( 2017-04-07 15:48:03 -0600 )edit

answered 2017-04-07 06:18:16 -0600

hkominos gravatar image

The logs look normal to me. The key line is Filter RetryFilter returned 0 hosts. Which means that there is no compute host with enough resources for your Vm. I would suggest.

1)shutdown all the compute nodes (from UI) and keep only 1 (or force through availability zones) 2)Check the nova and neutron logs on the compute nodes! to see what they report as status and what happens after they receive the request.

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I only have one device - controller node (no compute nodes) but I did find what is an issue. However I do not know how to fix it - Nova do not have any hypervisors, the table is empty. This is what it shows:

student gravatar imagestudent ( 2017-04-07 15:46:40 -0600 )edit

So that means that you have no compute nodes. You need compute nodes to spawn your Vms in.

hkominos gravatar imagehkominos ( 2017-04-10 05:54:29 -0600 )edit

answered 2017-04-06 12:57:51 -0600

juangallego gravatar image

I took a look at your logs, and I can tell you that I had the same issue installing manually What I did was to reinstall using packstack and it worked without any problem. My guess is that it was a configuration issue, maybe you want to try devstack or packstack to generate the configuration files you need.

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I would like to avoid using ready solutions, especially when I am that close to actually running it. This is the last thing which is stopping me from running it.

student gravatar imagestudent ( 2017-04-06 13:47:59 -0600 )edit

answered 2017-04-07 17:17:34 -0600

I found the problem it was /etc/nova/nova-compute.conf file where I had some random charachters. I think it was my configuration problem. I have different problem now.

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Asked: 2017-04-06 10:21:32 -0600

Seen: 925 times

Last updated: Apr 07 '17