04.ubuntu下kvm 命令行安装64位ubuntu报"Couldn't find hvm kernel for Ubuntu tree."的问题

1.安装ubuntu时使用的virt-install的配置：

virt-install 
--name test4 
--ram 1024 
--disk path=/data/01_ubuntu/ubuntu4.img,size=6 
--vcpus 1 
--hvm 
--os-type linux 
--network network=default 
--os-variant ubuntuquantal 
--graphics none 
--console pty,target_type=serial 
--location /data/00_osfile/ubuntu-16.04.1-server-amd64.iso 
--extra-args 'console=ttyS0,115200n8 serial'

报错如下：

ERROR Couldn't find hvm kernel for Ubuntu tree.
Domain installation does not appear to have been successful.

通过查资料发现，virt-install可以开debug模式的，加入--debug选项即可

2.virt-install的debug模式得到的结果：

[Wed, 30 Nov 2016 11:16:07 virt-install 26900] DEBUG (urlfetcher:268) local hasFile: Couldn't find /var/lib/libvirt/boot/virtinstmnt.xPL9y1/current/images/MANIFEST
[Wed, 30 Nov 2016 11:16:07 virt-install 26900] DEBUG (urlfetcher:89) Fetching URI: /var/lib/libvirt/boot/virtinstmnt.xPL9y1/install/netboot/version.info
Retrieving file version.info...                                                                                                                      |   58 B  00:00:00     
[Wed, 30 Nov 2016 11:16:07 virt-install 26900] DEBUG (urlfetcher:1164) Didn't find any known codename in the URL string
[Wed, 30 Nov 2016 11:16:07 virt-install 26900] DEBUG (urlfetcher:511) Detected distro name=Ubuntu osvariant=linux
[Wed, 30 Nov 2016 11:16:07 virt-install 26900] DEBUG (urlfetcher:268) local hasFile: Couldn't find /var/lib/libvirt/boot/virtinstmnt.xPL9y1/install/netboot/ubuntu-installer/i386/linux

这里就可以看出问题了，明明是64位的操作系统，为什么去找./install/netboot/ubuntu-install/i386/linux的路径

我们去看看iso文件中正确的路径是什么：

[root@11.102 01_ubuntu]$mount /data/00_osfile/ubuntu-16.04.1-server-amd64.iso /mnt
mount: /dev/loop2 is write-protected, mounting read-only

[root@11.102 01_ubuntu]$ls /mnt/install/netboot/ubuntu-installer/amd64/linux 
/mnt/install/netboot/ubuntu-installer/amd64/linux

基本确定，如果将路径的i386改为amd64，virt-install安装就没有问题。

debug模式剩余的log：

[Wed, 30 Nov 2016 11:16:07 virt-install 26900] DEBUG (urlfetcher:320) Cleaning up mount at /var/lib/libvirt/boot/virtinstmnt.xPL9y1
[Wed, 30 Nov 2016 11:16:07 virt-install 26900] DEBUG (cli:305)   File "/usr/share/virt-manager/virt-install", line 1077, in <module>
    sys.exit(main())
  File "/usr/share/virt-manager/virt-install", line 1071, in main
    start_install(guest, continue_inst, options)
  File "/usr/share/virt-manager/virt-install", line 775, in start_install
    fail(e, do_exit=False)
  File "/usr/share/virt-manager/virtinst/cli.py", line 305, in fail
    logging.debug("".join(traceback.format_stack()))

[Wed, 30 Nov 2016 11:16:07 virt-install 26900] ERROR (cli:306) Couldn't find hvm kernel for Ubuntu tree.
[Wed, 30 Nov 2016 11:16:07 virt-install 26900] DEBUG (cli:308) 
Traceback (most recent call last):
  File "/usr/share/virt-manager/virt-install", line 747, in start_install
    dom = guest.start_install(meter=meter, noboot=options.noreboot)
  File "/usr/share/virt-manager/virtinst/guest.py", line 491, in start_install
    self._prepare_install(meter, dry)
  File "/usr/share/virt-manager/virtinst/guest.py", line 304, in _prepare_install
    self.installer.prepare(self, meter)
  File "/usr/share/virt-manager/virtinst/installer.py", line 200, in prepare
    self._prepare(guest, meter)
  File "/usr/share/virt-manager/virtinst/distroinstaller.py", line 451, in _prepare
    self._prepare_kernel_url(guest, fetcher)
  File "/usr/share/virt-manager/virtinst/distroinstaller.py", line 360, in _prepare_kernel_url
    kernel, initrd, args = store.acquireKernel(guest)
  File "/usr/share/virt-manager/virtinst/urlfetcher.py", line 603, in acquireKernel
    {"distro": self.name, "type" : self.type})
RuntimeError: Couldn't find hvm kernel for Ubuntu tree.

3.修改virt-manager代码：

通过上面的报错，发现virt-manager使用python写的！正好想看什么源码来自，这个正好！

通过对virt-manager这一项目一步步debug，找到问题：

[root@11.102 ~]$grep -n -A22 "class DebianDistro" /usr/share/virt-manager/virtinst/urlfetcher.py
1076:class DebianDistro(Distro):
1077-    # ex. http://ftp.egr.msu.edu/debian/dists/sarge/main/installer-i386/
1078-    # daily builds: http://d-i.debian.org/daily-images/amd64/
1079-    name = "Debian"
1080-    urldistro = "debian"
1081-    os_variant = "linux"
1082-
1083-    def __init__(self, *args, **kwargs):
1084-        Distro.__init__(self, *args, **kwargs)
1085-
1086-        # Pull the tree's arch out of the URL text
1087-        self._treeArch = 'i386'
1088-        for pattern in ["^.*/installer-(w+)/?$",
1089-                        "^.*/daily-images/(w+)/?$"]:
1090-            arch = re.findall(pattern, self.uri)
1091-            if arch:
1092-                self._treeArch = arch[0]
1093-                break
1094-
1095-        self._url_prefix = 'current/images'
1096-        self._installer_dirname = self.name.lower() + "-installer"
1097-        self._set_media_paths()

发现基于Debian的系统，__init__方法中self._treeArch初始化时是i386，估计是virt-manager读取ubuntu的iso文件时，出了什么问题，没读出该系统是x86_64类型，将该值改为amd64,就可以了。

再次运行virt-install，成功进入ubuntu安装界面！

附：CentOS命令行使用KVM安装64位ubuntu报"Couldn't find hvm kernel for Ubuntu tree."的解决办法

grep -n -A21 'class DebianDistro' /usr/lib/python2.6/site-packages/virtinst/OSDistro.py 命令可以查看DebianDistro类的__init__方法

[root@2 virtinst]$grep -n -A21 'class DebianDistro' /usr/lib/python2.6/site-packages/virtinst/OSDistro.py
892:class DebianDistro(Distro):
893-    # ex. http://ftp.egr.msu.edu/debian/dists/sarge/main/installer-i386/
894-    # daily builds: http://people.debian.org/~joeyh/d-i/
895-
896-    name = "Debian"
897-    os_type = "linux"
898-
899-    def __init__(self, uri, arch, vmtype=None, scratchdir=None):
900-        Distro.__init__(self, uri, arch, vmtype, scratchdir)
901-        if uri.count("installer-i386"):
902-            self._treeArch = "i386"
903-        elif uri.count("installer-amd64"):
904-            self._treeArch = "amd64"
905-        else:
906-            self._treeArch = "i386"
907-
908-        if re.match(r'i[4-9]86', arch):
909-            self.arch = 'i386'
910-
911-        self._installer_name = self.name.lower() + "-" + "installer"
912-        self._prefix = 'current/images'
913-        self._set_media_paths()

改变__init__方法里的else：条件下面的一行，将"i386"改为"amd64"即可

- self._treeArch = 'i386'
+ self._treeArch = 'amd64'