我有一个原始的 Arch Linux VM，磁盘为 qcow2 格式。我最近对其进行了升级，但它停止工作了。每次运行时$ virsh start Arch我都会得到：
Starting version 243.78-2-arch
ERROR: device 'UUID=<ID>' not found. Skipping fsck
mount: new_root: can't find UUID=<ID>.
You are now being dropped into an emergency shell.
sh: can't access tty; job control turned off.
[rootfs ]#
我使用了一个 Live CD 并在其中进行了 chroot，我检查fstab发现我的/dev/sda1正在被挂载到 /，其 UUID 与错误消息中指示的相同。我重新运行了grub-mkconfig，mkinitcpio但错误消息仍然存在。
然后，我尝试创建一个新的虚拟机并使用以下命令保留我的驱动器：
$ sudo virt-install -n archlinux --description "Arch installation because of failure of Arch VM" --os-type=archlinux --ram=1024 --vcpu=1 --disk path='/var/lib/libvirt/images/Arch.qcow2',bus=virtio --network bridge:virbr0 --check path_in_use=off --import
但也没用。我最终决定在外部启动这个磁盘virsh，令我惊讶的是，下面的命令可以很好地启动我的虚拟机：
$ sudo qemu-system-x86_64 -drive file=/var/lib/libvirt/images/Arch.qcow2,format=qcow2 -m 1G
那么，我的 virsh 配置中的什么可能导致了这个问题？
这是该虚拟机的 dumpxml：
$ virsh dumpxml Arch
<domain type='kvm' id='20'>
<name>Arch</name>
<uuid>e8fa46c2-7b5e-42a5-87ae-f9eaccc13529</uuid>
<description>Arch Linux</description>
<memory unit='KiB'>2097152</memory>
<currentMemory unit='KiB'>2097152</currentMemory>
<vcpu placement='static'>1</vcpu>
<resource>
<partition>/machine</partition>
</resource>
<os>
<type arch='x86_64' machine='pc-i440fx-4.1'>hvm</type>
<boot dev='hd'/>
</os>
<features>
<acpi/>
<apic/>
</features>
<cpu mode='host-passthrough' check='none'/>
<clock offset='utc'>
<timer name='rtc' tickpolicy='catchup'/>
<timer name='pit' tickpolicy='delay'/>
<timer name='hpet' present='no'/>
</clock>
<on_poweroff>destroy</on_poweroff>
<on_reboot>restart</on_reboot>
<on_crash>restart</on_crash>
<pm>
<suspend-to-mem enabled='no'/>
<suspend-to-disk enabled='no'/>
</pm>
<devices>
<emulator>/usr/bin/qemu-system-x86_64</emulator>
<disk type='file' device='disk'>
<driver name='qemu' type='qcow2'/>
<source file='/var/lib/libvirt/images/Arch.qcow2'/>
<backingStore/>
<target dev='vda' bus='virtio'/>
<alias name='virtio-disk0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/>
</disk>
<disk type='file' device='cdrom'>
<driver name='qemu'/>
<target dev='hda' bus='ide'/>
<readonly/>
<alias name='ide0-0-0'/>
<address type='drive' controller='0' bus='0' target='0' unit='0'/>
</disk>
<controller type='usb' index='0' model='ich9-ehci1'>
<alias name='usb'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x7'/>
</controller>
<controller type='usb' index='0' model='ich9-uhci1'>
<alias name='usb'/>
<master startport='0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0' multifunction='on'/>
</controller>
<controller type='usb' index='0' model='ich9-uhci2'>
<alias name='usb'/>
<master startport='2'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x1'/>
</controller>
<controller type='usb' index='0' model='ich9-uhci3'>
<alias name='usb'/>
<master startport='4'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x2'/>
</controller>
<controller type='pci' index='0' model='pci-root'>
<alias name='pci.0'/>
</controller>
<controller type='ide' index='0'>
<alias name='ide'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/>
</controller>
<interface type='bridge'>
<mac address='52:54:00:7e:e5:69'/>
<source bridge='virbr0'/>
<target dev='vnet1'/>
<model type='virtio'/>
<alias name='net0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
</interface>
<serial type='pty'>
<source path='/dev/pts/8'/>
<target type='isa-serial' port='0'>
<model name='isa-serial'/>
</target>
<alias name='serial0'/>
</serial>
<console type='pty' tty='/dev/pts/8'>
<source path='/dev/pts/8'/>
<target type='serial' port='0'/>
<alias name='serial0'/>
</console>
<input type='mouse' bus='ps2'>
<alias name='input0'/>
</input>
<input type='keyboard' bus='ps2'>
<alias name='input1'/>
</input>
<graphics type='vnc' port='5901' autoport='yes' listen='127.0.0.1'>
<listen type='address' address='127.0.0.1'/>
</graphics>
<video>
<model type='cirrus' vram='16384' heads='1' primary='yes'/>
<alias name='video0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/>
</video>
<memballoon model='virtio'>
<alias name='balloon0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/>
</memballoon>
</devices>
<seclabel type='dynamic' model='dac' relabel='yes'>
<label>+65534:+992</label>
<imagelabel>+65534:+992</imagelabel>
</seclabel>
</domain>