Troubleshoot your cinder installation
This section is intended to help solve some basic and common errors that are encountered
during setup and configuration of Cinder. The focus here is on failed creation of volumes.
The most important thing to know is where to look in case of a failure. There are two log
files that are especially helpful in the case of a volume creation failure. The first is the
cinder-api log, and the second is the cinder-volume log.
The cinder-api log is useful in determining if you have
endpoint or connectivity issues. If you send a request to
create a volume and it fails, it's a good idea to look here
first and see if the request even made it to the Cinder
service. If the request seems to be logged, and there are no
errors or trace-backs then you can move to the cinder-volume
log and look for errors or trace-backs there.
There are some common issues to look out for. The following describes
some common issues hit during configuration and some suggested solutions.
Create commands are in cinder-api log
with no error
state_path and volumes_dir settings
Cinder uses tgtd
as the default iscsi helper and implements persistent targets.
This means that in the case of a tgt restart or
even a node reboot your existing volumes on that
node will be restored automatically with their
original IQN.
In order to make this possible the iSCSI target information needs to be stored
in a file on creation that can be queried in case of restart of the tgt daemon.
By default, Cinder uses a state_path variable, which if installing via Yum or
APT should be set to /var/lib/cinder/. The next part is the volumes_dir
variable, by default this just simply appends a "volumes" directory to the
state_path. The result is a file-tree /var/lib/cinder/volumes/.
While this should all be handled for you by you installer, it can go wrong. If
you're having trouble creating volumes and this directory does not exist you
should see an error message in the cinder-volume log indicating that the
volumes_dir doesn't exist, and it should give you information to specify what
path exactly it was looking for.
persistent tgt include file
Along with the volumes_dir mentioned above, the iSCSI target driver also needs
to be configured to look in the correct place for the persist files. This is a
simple entry in /etc/tgt/conf.d, and you should have created this when you went
through the install guide. If you haven't or you're running into issues, verify
that you have a file /etc/tgt/conf.d/cinder.conf.
If the file is not there, you can create it easily by doing the
following:
sudo sh -c "echo 'include /var/lib/cinder/volumes/*' >> /etc/tgt/conf.d/cinder.conf"
No sign of attach call in the cinder-api
log
This is most likely going to be a minor adjustment to your
nova.conf file. Make sure that your
nova.conf has the following
entry:
volume_api_class=nova.volume.cinder.API
And make certain that you EXPLICITLY set enabled_apis as the default will include
osapi_volume:
enabled_apis=ec2,osapi_compute,metadata
Failed to create iscsi target error in the cinder-volume.log
2013-03-12 01:35:43 1248 TRACE cinder.openstack.common.rpc.amqp ISCSITargetCreateFailed: Failed to create iscsi target for volume volume-137641b2-af72-4a2f-b243-65fdccd38780.
You may see this error in cinder-volume.log after trying to create a volume that is 1 GB. To fix this issue:
Change content of the /etc/tgt/targets.conf from "include /etc/tgt/conf.d/*.conf" to:
include /etc/tgt/conf.d/cinder_tgt.conf:
include /etc/tgt/conf.d/cinder_tgt.conf
include /etc/tgt/conf.d/cinder.conf
default-driver iscsi
Then restart tgt and cinder-* services so they pick up the new configuration.