CommunicationError: Error communicating with http://XX.XX.XX.XXX:9292 [Errno 111] ECONNREFUSED

Some times, when you trying to deploy a machine, you may ended up with the following error. In my case, the infrastructure is as follows.

One Controller Node, Two compute Nodes, One cinder and One Neutron node. All are Centos 6.6 with Icehouse Release.

2013-10-30 12:34:03.574 15487 TRACE nova.api.openstack CommunicationError: Error communicating with http://192.168.72.100:9292 [Errno 111] ECONNREFUSED

Even your glance_host configuration parameter in the /etc/cinder/cinder.conf is right, you will face this issue.  To resolve this issue, add the following in the /etc/nova/nova.conf file of Controller node.

image_service=nova.image.glance.GlanceImageService

glance_api_servers=192.168.72.145:9292  #IPis the Glance Host

Restart the Nova scheduler and API services in Controller node.

You are good to Go !!!

When you want to use CEPH as the backend of Openstack, you may face this error in ceph admin while MAP your newly created volume.

    ERROR: modinfo: could not find module rbd
    FATAL: Module rbd not found.
    rbd: modprobe rbd failed! (256)

This is because RBD module is not loaded in the Kernel. I have searched a lot in internet on how to enable RBD module in the Kernel. I am summarise my finding here.



CURRENT SYSTEM

COMPONENT      CINDER

OPENSTACK        ICEHOUSE

OS                       CENTOS 6.6

KERNEL              3.18.0 (64)

I had updated kernel to the latest build using the following way.

#rpm --import http://elrepo.org/RPM-GPG-KEY-elrepo.org
#rpm -Uvh http://elrepo.org/elrepo-release-6-5.el6.elrepo.noarch.rpm
#yum --enablerepo=elrepo-kernel install kernel-ml # will install 3.11.latest, stable, mainline

After finishing the installation, change the default boot kernel to newly installed one

#vim /etc/grub.cfg

Change the following 1 TO 0

default=0

Reboot the system, now you will have new kernel with 3.18.1-1

#uname -r

3.18.1-1

Try to search for RBD Module.

[root@cinder ~]# lsmod | grep rbd
rbd                    57971  0
libceph               166955  1 rbd
[root@cinder ~]#