VNC and firewalld on Centos 7 compute node

By default firewalld service is enabled and may cause troubles in accessing via VNC to instances running on Centos compute node.

Solution:

By default zone=public is used, so it is enough just to add 5900/5901 ports or/and vnc-server service to this zone:

 Result:

Nova installation on Centos 7

RabbitMQ

After starting rabbitmq-server service it is not possible to change password using:

 Error:

Solution:
In file /etc/systemd/system/multi-user.target.wants/rabbitmq-server.service change

to – add sudo

And restart rabbitmq-server:

 

Nova incompatibility

Packages for nova which are downloaded with yum contain nova version which is incomaptible with that is running on controller node (Ubuntu):

Controller (Ubuntu 14.04):

Compute (Centos 7):

Problem is described here:
https://ask.openstack.org/en/question/57296/juno-centos-7-buildabortexception-build-of-instance-aborted-failed-to-allocate-the-networks-not-rescheduling/?answer=57883#post-id-57883

Solution:
Install packages from EPEL repo manually (only 3 days older):

https://repos.fedorapeople.org/repos/openstack/openstack-juno/epel-7/

Packages to install:

I had to forcefully install them using rpm -ivh –force then I restarted openstack-nova-compute service.
After this instances spawned correctly, yet I could not reach them (iptables rules missing, so I disabled iptables).

DHCP addresses got distributed to the instances correctly and I could reach internet from them via my Ubuntu-AIO which acts as a gateway to the internet as well.