A：

• 现象：

报错如下：

"org.zstack.header.vm.APICreateVmInstanceEvent":{"success":false,"apiId":"9ebc212
f00ea45bbaa91e1e420230921","headers":{"schema":{}},"error":{"code":"SYS.1006","cause":{"code":"HOST.1005","description":"Failed to start vm on hypervisor","details":"failed to start vm[uuid:2da983e8b5a34a459bb71a0d705b0bba name:vm-qge5] on kvm
host[uuid:b7a14605c6b042e0b2da17ae329ea70a, ip:10.79.186.30], because Traceback (most recent call last):\n File \"/var/lib/zstack/virtualenv/kvm/lib/python2.7/site-packages/kvmagent/plugins/vm_plugin.py\", line 2721, in start_vm\n self._start_vm(cmd)\n File
\"/var/lib/zstack/virtualenv/kvm/lib/python2.7/site-packages/kvmagent/plugins/vm_plugin.py\", line 2664, in _start_vm\n 'unable to start vm[uuid:%s, name:%s], libvirt error: %s' % (cmd.vmInstanceUuid, cmd.vmName, str(e)))\nKvmError: unable to start vm[uuid
:2da983e8b5a34a459bb71a0d705b0bba, name:vm-qge5], libvirt error: internal error:early end of file from monitor, possible problem: 2017-03-12T10:49:18.661399Z qemu-kvm: -drive file=rbd:pri-v-r-a5486c5605a8499dbe3ca79ee3ca87c4/a28d86db519c48
ef9e4c50a3f8e27305:id=zstack:key=AQD4HsVYwfgaMBAAxBNUtDw1wzhitURDrUMM9g==:auth_supported=cephx\\;none:mon_host=10.79.186.112\\:6789,format=raw,if=none,id=drive-virtio-disk0: error reading header from a28d86db519c48ef9e4c50a3f8e27305: Function not implemented\n"},"description":"An operation failed","details":"failed
to start vm[uuid:2da983e8b5a34a459bb71a0d705b0bba name:vm-qge5] on kvm host[uuid:b7a14605c6b042e0b2da17ae329ea70a, ip:10.79.186.30], because Traceback(most recent call last):\n File \"/var/lib/zstack/virtualenv/kvm/lib/python2.7/site-package
s/kvmagent/plugins/vm_plugin.py\", line 2721, in start_vm\n self._start_vm(cmd)\n File\"/var/lib/zstack/virtualenv/kvm/lib/python2.7/site-packages/kvmagent/plugins/vm_plugin.py\", line 2664, in _start_vm\n 'unable to start vm[uuid:%s, name:%s], libvirt error: %s
' % (cmd.vmInstanceUuid, cmd.vmName, str(e)))\nKvmError: unable to start vm[uuid:2da983e8b5a34a459bb71a0d

• 原因：

rbd无法读取镜像文件头文件，很可能是Ceph存储本身的问题。ZStack定制版ISO的qemu-kvm 2.6.0安装时默认带librbd 0.94客户端。如果用户部署了Ceph10.2.x或着12.2.x，librbd老版本客户端不支持新版本的后端。

• 解决方案：

用户需在计算节点上手动安装或升级与所部署Ceph版本对应的librbd客户端包。