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

asked 2015-10-27 13:21:12 -0500

Vini.g.fer gravatar image

updated 2015-10-28 07:19:10 -0500

I've been following the docs for liberty release, and got stuck when trying to launch a private instance on a private network. Launching a public instance on a public network runs fine! I can even lauch 2 or 3 instances, but whenever I try to launch a private instance I get this error:

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

This happens either using the web interface (Horizon) or the linux terminal. Already ran

nova-manage service describe_resource compute

which returned this:

HOST                              PROJECT     cpu mem(mb)     hdd
compute         (total)                         2    2001      35
compute         (used_now)                      1    1024       1
compute         (used_max)                      1     512       1

Since it is a cirros image with tiny flavor (512MB) seems there are enough resources. What should I do to resolve this issue? I'm testing openstack on VMs with virtualbox.

Update 1:

By public instance, I actually meant "Launch an instance on the public network", as this link: (

Similar idea goes to private instance: That actually means "Launch an instance on a private network", as this link: (

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Could you, please , explain what you call public instance and what you call private instance.
Define , please , as UPDATE 1 to your question.

dbaxps gravatar imagedbaxps ( 2015-10-27 14:33:41 -0500 )edit

Agree with dbaxps. Also , please verify the resources allocation for 'what you call private instance' . Are sufficient resource allocated. gravatar ( 2015-10-27 22:54:19 -0500 )edit

I did verified resources My host machine is an Ubuntu 14.04 PC with 8GB of RAM, my compute node is a VM with 2GB of RAM, and 40GB of storage (about 38GB is free now).

What logs should I check for finding out what is wrong? What other info/files might help?

Vini.g.fer gravatar imageVini.g.fer ( 2015-10-28 07:24:20 -0500 )edit

If I understand you right, you don't need create neutron routers, to bind L2 and L3 neutron's layers.

dbaxps gravatar imagedbaxps ( 2015-10-28 07:25:04 -0500 )edit

I think you mean ML2 instead of L2 right? Why shouldn't I need routers?

Vini.g.fer gravatar imageVini.g.fer ( 2015-10-28 07:59:55 -0500 )edit

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answered 2015-10-29 08:29:54 -0500

Vini.g.fer gravatar image

It seems the issue of creating VMs in a private network was caused by a failure in neutron’s configuration: configuration in /etc/neutron/plugins/ml2/linuxbridge_agent.ini should have used eth1 (physical_interface_mappings variable) and the local ip should have been (local_ip variable).

I was using eth0 (Brigde adapter, open to internet in VirtualBox) and IP (controller IP).

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Asked: 2015-10-27 13:21:12 -0500

Seen: 7,577 times

Last updated: Oct 29 '15