Hi, all We met an issue while doing the nbd related test, will you please help to review if this issue is a bug? Thank you! ================================================= Subject: [s3-bug-review] [RHEL7] [Virtual disks] Met error messages while the guest OS booting up on a nbd device. Description: Start a guest with only one nbd device and with a linux OS installed on the nbd device, "virsh create" return successfully, but meet error messages while the guest OS booting up. Version: libvirt-client-1.1.1-29.el7.x86_64 qemu-kvm-1.5.3-60.el7.x86_64 kernel-3.10.0-121.el7.x86_64 How reproducible: 100% Steps to Reproduce: 1. start nbd server on the server host. #nbd-server 10809 /var/lib/libvirt/images/r7g-qcow2.img 2. create a domain with xml as bellow. # virsh create r7g-nbd.xml Domain r7g-qcow2 created from r7g-nbd.xml # virsh dumpxml r7g-qcow2| grep disk -A 7 <disk type='network' device='disk'> <driver name='qemu' type='qcow2'/> <source protocol='nbd'> <host name='10.66.106.34' port='10809'/> </source> <target dev='sda' bus='scsi'/> <alias name='scsi0-0-0-0'/> <address type='drive' controller='0' bus='0' target='0' unit='0'/> </disk> # ps -ef| grep qemu-kvm| grep nbd qemu 15724 1 99 09:58 ? 00:00:47 /usr/libexec/qemu-kvm -name r7g-qcow2 ...... -drive file=nbd:10.66.106.34:10809,if=none,id=drive-scsi0-0-0-0,format=qcow2 -device scsi-hd,bus=scsi0.0,channel=0,scsi-id=0,lun=0,drive=drive-scsi0-0-0-0,id=scsi0-0-0-0,bootindex=1 ...... 3. login to the guest, the console output error messages and fail to booting up. Actual results： As described. Expected results: The guest can boot up successfully. Additional info: Attached screen-shot and log files. Regards, chhu