i got the same problem there is no nova compute in nova service and the file /var/log/nova/nova-compute.log does not exit

how can i fix it? can i add the nova-compute service without reinstalling all?

This is a common error when the nova-scheduler can't find any suitable compute node to launch instance.

1) Check the output of 'nova-manage service list'. If 'nova-compute' and 'libvirt-bin' services are working fine, then it should show enabled and status should be :-)

2) If any compute node is available and enabled, check /var/log/nova/nova-compute.log in that node and see if you could find any errors. (see the old logs , as you cant see any logs while launching instance as the the request would be stopped at the scheduler itself)

3) If everything is fine and clean, then the compute node should be lack of resources. In this case, you can create a small flavor and try to launch instance with that flavor.

It is mostly because you don't have the resources properly. Always try to use the small images rather than big ones and select the flavor m1.nano, m1.tiny( again it depends on how much ram and swap memories are available, In my case my swap space used to be 100% utilized and ram used to be 83% to 87% ). Don't go for flavors like medium, large, etc.., which causes the errors like what you mentioned.

检查logs目录下的出错信息，我的原因是BIOS没有开启VT，kvm模块未加载 https://wiki.ubuntu.com/kvm http://docs.openstack.org/juno/config-reference/content/kvm.html (http://docs.openstack.org/juno/config...)

Hello! I got the same issue, and restarting the service nova-scheduler solves the case.

Before powering on the Instance, just tail logs. ( tail -f /var/log/nova/* | grep -i error ). so whenever you will receive error while creating instance, you can troubleshoot easily with the error, which is self explanatory for most of them. This procedure has helped me fix many of the issues.

I solved it by changing "Quota" for my "Demo" project of "myUser".

I had the same problem. I have installed OpenStack Training Labs. It has Project named Demo in which I was working. I had only 1Gb of RAM as Quota for that project. I changed the limit to 10Gb and I was able to launch the instance.

To this you have to be logged in as Admin (or have admin rights): Identity -> Projects -> Demo (you project name)

Hope it helps! :-)