Ask Your Question

New compute node addition - VMs not launching with new compute node

asked 2016-09-23 07:21:51 -0500

ajithpathiyil gravatar image

Hi All,

My new compute node addition is successful and also able to see the new compute node through my dashboard (All "Compute services" and related "Network Agents" for all the compute nodes (Existing and new one added) are enabled and up.

But all my instances launch are hitting the existing compute node and when reaching its threshold, new VMs are not being launched in the new compute node, Instead it tries to launch with existing compute node and it fails with "No valid hosts" generic error.

My existing compute node & new node versions

Release = Liberty nova --version = 2.30.1 nova-compute = 12.0.0 neutron-version = 3.1.0 neutron-linuxbridge-agent = 7.0.0

I am sure, I am missing something and have the doubt with below dbsync command (In the below URL), But since it is the db command, I am releuctant to fire it without confirmation.

su -s /bin/sh -c "nova-manage db sync" nova


Any help in this regard should be helpful.

edit retag flag offensive close merge delete

2 answers

Sort by ยป oldest newest most voted

answered 2016-09-24 03:30:47 -0500

nd gravatar image

Is your nova-compute service running fine on the new compute node [check the /var/log/nova/nova-compute.log on compute node]

Check nova service-list [after sourcing appropriate keystonerc file for admin] compute service should show enabled and up

Have you configured the additional compute node as different host aggregate / availability zone - then in the /etc/nova/nova.conf ensure you have AvailabilityZoneFilter added for scheduler_default_filters ; and then while launching the instance select the appropriate availability zone.

regs, nd

edit flag offensive delete link more

answered 2016-09-24 04:16:00 -0500

Ajaycs gravatar image

if host aggregate is not set VM are created in default availability zone and there may not enough resource to launch the VM . set host aggregate /availability zone for new compute and use same availability zone while create new VM.

on many occasions network miss configuration on new compute lead to this issue.please check network part on new compute.

/var/log/nova/nova-compute.log will point the issue on compute node.

check all node (block, object, controller, existing compute) are resolving from new compute and visa-versa.

Regards, Ajay

edit flag offensive delete link more


Hi Ajay, I have the new compute added to a newly created host aggregate and within a new availability zone. Error in /var/log/nova/nova-compute.log, Below is the error NovaException: Failed to add bridge: sudo:no tty present and no askpass program specified All nodes are able to ping eachother

ajithpathiyil gravatar imageajithpathiyil ( 2016-09-28 07:08:58 -0500 )edit

Get to know Ask OpenStack

Resources for moderators

Question Tools

1 follower


Asked: 2016-09-23 07:21:51 -0500

Seen: 312 times

Last updated: Sep 24 '16