April 10, 2016 - David Sokolik
Openstack Error: Build of instance aborted: Block Device Mapping is Invalid
During instance deployment you receive the following error [Error: Build of instance GUID aborted: Block Device Mapping is Invalid.] but as most openstack error this means nothing to most people.
To understand the full nature of this error we need to check the logs.
now we need to examine the last lines of the log file (assuming no further VM’s were tried to be ran since this error was received.) in the logs there should be an error simlar to the following:
ERROR oslo_messaging.rpc.dispatcher ImageUnacceptable: Image a43efd7e-7342-4e08-8979-3a01070e28d6 is unacceptable: Size is 16GB and doesn’t fit in a volume of size 12GB.
Now here we can see a readable error, the volume size of the image is larger then the volume size we tried to assign to the actual VM, now while the disk size might be lower then the size reported the OS itself expects a minimum volume size of 16GB in this particular case while our image it self was only 4GB.