Comment 4 for bug 1931716

Nova logs

Unexpected libvirt error while detaching device vdb from instance e3d6fd2b-7357-4d19-bcb4-482d97d332e5: operation failed: disk vdb not found: libvirt.libvirtError: operation failed: disk vdb not found

This means the code hit an unrecognized error[1]. It is not DEVICE_MISSING (99)[2]. Even thought the error message suggest that.

I will push a patch that logs the error code so we can add that to the handled errors.

[1] https://github.com/openstack/nova/blob/245433b826cc7178512c913df59caa9e73895f60/nova/virt/libvirt/driver.py#L2540
[2] https://github.com/openstack/nova/blob/245433b826cc7178512c913df59caa9e73895f60/nova/virt/libvirt/driver.py#L2502